“Want to develop vaccines in Africa? Then invest in expertise and infrastructure” 

Understanding biological systems is critical to the prosperity, and possibly, survival of the human race. Without it, we are threatened by disease, energy and food insecurity, pollution and climate change.

The COVID-19 pandemic has shown how important it is to have both national and international approaches to research and development with access to the right type of world class equipment, training and expertise.

In this article, The Conversation unpacks how our three-year START programme (Synchrotron Techniques for African Research and Technology) – funded with a £3.7 million Global Challenges Research Fund (GCRF) grant from the UK Research and Innovations’ Science and Technology Facilities Council – substantially prepared South Africa’s capacity to do this work.

START trained students and postdoctoral research assistants at eight South African universities and the country’s National Institute for Communicable Disease (NICD). It also allowed access to the UK’s national synchrotron, Diamond Light Source.

Structural Biology research included SARS-CoV-2 (COVID-19), snakebite venom, HIV, tuberculosis, malaria, human papilloma virus, cardiovascular disease, as well as equine diseases, and many more. Work has also been done to create industrial enzymes for the manufacture of medicines and commodity chemicals.

“The GCRF START initiative provided an exceptional combination of expertise and experimental resources.”

Read the full article here:

The application of in situ and operando methods in catalysis – opportunities for UK-Africa collaboration through START

“When I saw the opportunity to be a part of a GCRF START team in the UK, I was very motivated to join the group. My aim is to make connections with people and be the link between researchers in Africa and groups in the UK which brings benefit to both. START has made my dream real; it has enabled something one can’t do by oneself because you need a team, and you need funding. There is no other better way to do our research than through the START collaboration.”

Dr Khaled Mohammed, University of Southampton, UK

Our team at the University of Southampton (UK) is focussed on the application of in situ and operando methods to all aspects of catalysis; this covers all areas of a catalyst’s “life-cycle” – from formation and operational behaviour, to eventually understanding what causes it to lose performance. A catalyst is a chemical substance widely used in large-scale chemical industry to enhance reactivity and selectivity towards target products of the reaction of interest without itself being consumed in the reaction.

However, the complex nature of such material requires an advanced tool to understand its behaviour under operating conditions fundamental to the chemical industry and in the drive to increase sustainability for the future of our planet. Extensive knowledge and experience in using synchrotron radiation sources is therefore vital to understand the complex nature of catalysts and to develop new technologies here in the UK and globally. Through the START collaboration, our knowledge and hands-on-experience in this area is shared with our African partners as they develop their own catalysis and synchrotron research programmes.

My name is Khaled Mohammed, and I am a Postdoctoral Research Fellow (PDRF) in Synchrotron Methods for Catalysis within Chemistry at the University of Southampton. Funded by the GCRF START grant, I joined START in October 2019 to work with Dr Peter Wells’ team – Peter is a GCRF START Co-Investigator (Co-I) and an Associate Professor within Chemistry at Southampton, holding a joint appointment with the UK’s national synchrotron, Diamond Light Source (Diamond). I joined the START project only a matter of months before the global COVID-19 pandemic and research has been challenging in this period. Despite this, I have contributed to several published studies[1] as a GCRF START PDRF.

Here I explain my perspectives on what START means as an African researcher in the UK.  My role involves contributing to British and international research, and I see myself as an ‘ambassador’ for my country (Egypt), making connections to people and being a link between researchers in the UK and those in other African countries.

GCRF START Postdoctoral Research Fellow, Dr Khaled Mohamed, preparing a wide range of materials including supported metal/metal oxides, and tailored porous framework architectures with well isolated active sites for directed catalysis at the University of Southampton. Photo credit: Khaled Mohammed. ©Diamond Light Source

Joining the START network at the University of Southampton, UK

My experience using such facilities, with particular emphasis on operando and time-resolved X-ray absorption fine structure spectroscopy (XAFS), dates back to my PhD studies at the University of Southampton (2010 – 2014) and my previous role as a Research Associate at University College London (2013 – 2015), where our group had the opportunity to use the facilities at the Research Complex at Harwell and the Beamline Allocated Group (BAG) at Diamond. In November 2015, I decided to go back to my home country, Egypt, to start a new academic role at Sohag University as a Lecturer in chemistry. I was very keen and motivated about the role with its many teaching activities. A few months later, however, I realised that my scientific research was limited in this role by the fact that there was no access to a synchrotron, which does not exist on the African continent.

On the bright side, however, I had the opportunity to speak with my colleagues in Egypt who have no experience in using such synchrotron tools and I could share with them the knowledge I had gained in the UK.  In addition, I could give lectures and seminars on the key questions about synchrotrons to the next generation of scientists: How does a synchrotron work?  What type of experiments do we do with synchrotrons? Which beamlines are available to use to support our research?

My colleagues in Egypt were excited about this subject, but it was also a challenge as the facilities are good but not good enough to do the level of advanced experiments / topics that one can do with synchrotrons. People are very motivated to do these advanced topics, such as characterisation of materials for catalysts and applications, but the problem is we do not have the funding or access to these kinds of experiments. Therefore, when I saw the opportunity to be a part of a START team, I was very motivated to join the group at Southampton.

GCRF START Postdoctoral Research Fellow, Dr Khaled Mohammed and GCRF START CO-I, Dr Peter Wells at the University of Southampton, UK. Photo Credit: Khaled Mohammed. ©Diamond Light Source

Catalysts and synchrotrons for renewable energy – the hydrogenation of furfural for biofuels

I was born in Sohag city, Egypt, where I lived for most of my childhood. I loved studying science at school, especially the physical sciences, and I dreamt about becoming a scientist to help provide power for the city where I lived – at that time access to electricity was very intermittent.  Outside the city, I wanted to help people who lived in the countryside where, at that time, there was no electricity at all. Later, my dreams shifted to chemistry and I was motivated and inspired to develop pharmaceuticals. I had seen my grandfather suffering with illness and die prematurely due to lack of available medicines.

Today, I find myself inspired by these experiences working in catalysis with applications in renewable energy where waste biomass is converted to liquid biofuels (Bioenergy), or waste CO2 is converted to high value chemicals that can be used in our daily life, or as an alternative to fossil fuels. These applications rely on catalysts but to make this process more sustainable and efficient, advanced techniques are required to understand how the catalysts work under operating conditions. It is a big challenge for African researchers to access the facilities and techniques needed for this type of work. Like my dreams when I was younger, I take great pride in trying to provide something useful to society. What I love about START is that it brings these dreams to reality.

A good example of the kind of research I have collaborated on is the hydrogenation of furfural. Furfural is a bio-derived molecule and can be converted to many useful products, including the generation of liquid fuels; it is therefore a renewable energy feedstock. However, bio-derived compounds are highly functionalised, this means they have many parts of the molecular structure that can undergo chemical change. Palladium (Pd) nanoparticles are widely used as an active component in furfural hydrogenation – a specific type of reaction that involves the addition of hydrogen to a compound – however, selectivity to specific products is a big challenge. In addition, Pd is a very scarce element and there are significant concerns about the sustainability of using such elements, both from an economic perspective and the environmental impact of mining such rare materials.

In our recent paper, [ACS Catal. 2020, 10(10), 5483–5492 (https://pubs.acs.org/doi/10.1021/acscatal.0c00414)], we demonstrated that a Pd/NiO catalyst can hydrogenate furfural using a dual site process; the Pd splits the H2 molecule into adsorbed hydrogen atoms onto the Pd surface, the adsorbed hydrogen then migrates onto the NiO surface where the furfural molecule is selectively transformed. For materials like this, we need to use advanced tools at Diamond Light Source, e.g. X-ray absorption spectroscopy, to understand more about our materials and their unique properties that allow them to function as catalysts.

GCRF START Postdoctoral Research Fellow, Dr Khaled Mohammed, at the University of Southampton, UK. Photo Credit: Khaled Mohammed ©Diamond Light Source

In the shadow of the Covid-19 pandemic – facilitating UK-African research through cross-disciplinary teamwork

“START has and continues to be a fantastic opportunity for the UK to work in concert with our African partners. Our futures are intertwined; we share the same global challenge of treading more lightly on our planet, be it to mitigate climate change or to preserve our natural world, whilst simultaneously sustaining our growing populations. New functional materials are needed to underpin the emerging sustainable technologies that allow us to tackle these challenges and START is an important gateway for sharing the tools and expertise to accelerate these advances.”

Dr Peter Wells, University of Southampton, UK

During the pandemic, the GCRF START grant has enabled us to stay productive and self-motivated, for which we are truly grateful. Although access to laboratory and synchrotron facilities has been limited, we have been able to continue our work remotely. We set goals including research activities, data reduction/analysis and submitting new beamline proposals. In addition, we participated in many on-line activities including workshops, seminars, and social activities with all participants in START.  

The environment in the group here at Southampton has been excellent. There are things you can’t just learn by talking; we have learnt by doing research-based experiments together. Peter has taught me a lot. If I do an experiment, I give the idea to Peter, and then we do some tests to validate which beamline to use and what we need to adjust and optimise before we go ahead.

When I was in Egypt – before I got involved in START – I tried to do collaborations with people here in the UK.  I could do the basics and prepare materials, but I couldn’t correlate the structure-performance relationship without beamtime experiments. Being here in the UK, interacting with experienced scientists, has enabled me to see what is new and to push things forward through START, sharing what I learn with my African colleagues.

A great achievement has been international collaborations across a range of disciplines. After joining START in 2019, I found the group already working with Professor Michael Claeys’ Group at the University of Cape Town (UCT) in South Africa. I soon got involved in this project working with Dr Mohamed Fadlalla and Chris Mullins on research using the B18 beamline at Diamond to assess, in situ, the effect of substituents in ferrite structure with the general formula of AB2O4. These are used in a wide range of catalytic reactions including the Haber-Bosch process, water-gas shift reaction, dehydrogenation of ethylbenzene, and Fischer-Tropsch synthesis (FTS) to produce liquid hydrocarbons/fuels.

I was able to assist Mohamed with his experiment in December 2020. We had to submit a proposal and get it accepted (to do this you have to submit initial results like a proof of concept). Once accepted, the experiment had to be done in a specific time frame. But before Mohamed came over to the UK to conduct the experiment, tests had to be carried out for optimisation of the materials. This takes time so I did this first to ensure the experiment ran smoothly when he arrived.  

There are lots of other things that must be organised and managed before experiments like these, therefore my role has been to optimise as much as possible to increase the chance of success. Since then, we have assisted Mohamed and his colleagues in data analysis for publication. This successful beamtime experiment motivated us to explore new ideas, for example, in making catalysts with well-isolated active sites – mainly cobalt in tetrahedron sites to be used in preferential oxidation of carbon monoxide.

GCRF START Co-I, Professor Michael Claeys (L) and Research Officer, Dr Mohamed Fadlalla (R), at the University of Cape Town’s Centre for Catalysis, South Africa. Photo credit: Rebekka Stredwick. ©Diamond Light Source.

The future with START – ‘follow on’ opportunities for UK and African energy materials research

“START is a fantastic opportunity for the UK to work in concert with our African partners to tackle shared challenges. It is clear that the excitement generated can be inspirational and helps to further integrate research partnerships.”  – Dr Peter Wells, University of Southampton, UK

We are discussing our new research ideas going forward with Mohamed and another colleague of his, GCRF START Postdoc – Dr Thulani Nyathi – and have set goals and tasks for two ‘follow-on’ projects currently in the pipeline. As a result, I am in the process of sending some samples to Mohamed and Thulani for the preferential oxidation of carbon monoxide. This research has the dual benefit of reducing the harmful effects of carbon monoxide and using the carbon monoxide captured to make useful chemicals for energy, such as fuel cell storage to power vehicles and other devices.

We are also very impressed with the facilities and equipment at UCT, some of which we don’t have here in the UK, and which could be beneficial to access in the future. On a practical level, routine visits are important for hands-on experience (sadly due to the Covid-19 pandemic my visit to UCT in 2020 was cancelled), therefore continuing remote options in the meantime is vital for sharing ideas.

GCRF START Postdoctoral Research Fellow, Dr Khaled Mohammed, next to the vertical stainless-steel temperature-programmed reactor at the University of Southampton (UK) with temperature-programmed controller for conducting solid-gas phase catalytic reactions under different conditions up to 1500C. Photo Credit: Khaled Mohammed ©Diamond Light Source

Perspectives from our collaborators in South Africa on the impact of START

Here I want to share testimonials from Dr Thulani Nyathi and Dr Mohamed Fadlalla demonstrating their perspectives on our UK-Africa collaborations.

Thulani said,

“I first worked with Dr Peter Wells’ group prior to the GCRF START programme through a collaboration also involving the UK Catalysis Hub (located on the Harwell Science and Innovation Campus in Oxfordshire) and with Dr Emma Gibson’s group in Chemistry at the University of Glasgow, funded by the EPSRC (grant EP/R026815/1). This included my first visit to a synchrotron facility – Diamond Light Source – and my first exposure to two in situ techniques, XAS and DRIFTS, which were used to study supported cobalt oxide catalysts for the preferential oxidation of carbon monoxide (CO-PrOx).

This collaboration proved to be highly successful as it was concluded with a very good publication[2] in ACS Catalysis in 2019. Through the GCRF START programme (grant ST/R002754/1), I have continued to work with Peter’s group and Emma’s group, using the Block Allocation Group sessions administered by the UK Catalysis Hub, to analyse fresh and spent catalysts for the CO-PrOx reaction. I was then able to conclude my PhD thesis in September 2020 and publish a second paper in Applied Catalysis B: Environmental in June 2021[3].

There exists on-going work between the Southampton and UCT groups where we try to study substituted iron oxide and alloy catalysts for use in the hydrogenation of carbon dioxide (a greenhouse gas) to value-added chemicals. This work has already involved a trip to Diamond in 2019 and the results obtained will feature in a paper we aim to publish later in 2021. I hope to make more trips to Diamond and to continue working with the Southampton and Glasgow groups in the upcoming years.”

GCRF START Postdoctoral Research Fellow, Dr Thulani Nyathi from the University of Cape Town’s Centre for Catalysis, South Africa. Photo Credit: Linda Vos. © http://www.lindavos.co.za

Mohamed said,

“The highly seamless collaboration with Dr Peter Wells and Dr Khaled Mohammed from the University of Southampton has led to a more profound collective understanding of the catalytic materials under activation and under working conditions using in situ and ex situ synchrotron-based techniques. Owing to the successful and harmonious collaboration between the two research groups thus far, further partnership is in the works to investigate catalyst structure/activity/selectivity correlations in the energy material field.”

Dr Mohamed Fadlalla at the University of Cape Town’s Centre for Catalysis in South Africa conducting analysis of the CO2 hydrogenation over iron-based alloys via two-dimensional gas chromatography x gas chromatography (2D GC x GC). Photo credit: Rebekka Stredwick © Diamond Light Source

START’s achievements and the future – “a great work for great value”

When I look back at what has been achieved and then look forward to the future, I ask myself the question: If there wasn’t a START network/project, how would people who don’t know about synchrotron techniques know about these opportunities? START not only transfers knowledge and enhances capacity, but it also builds awareness a bit like an advertisement. It helps us know where and how to apply to synchrotrons like Diamond for beamtime and shows us what is possible and how to do the experiments in the right way. And synchrotron techniques give unprecedented insights essential for our research. If there hadn’t been a GCRF START grant to fund these possibilities, it would have delayed our research because collaborations like START boost and speed up the process and findings.

In Africa we need the fundamental facilities to train the next generation ready to use synchrotrons. More locally, in Egypt, we need capacity-building facilities to do initial experiments and fundamental research. For example, a catalytic reactor would be very useful for scientists to do some reactions. We can do the preparation – we can buy the chemicals – but to do the catalytic reactions we need a reactor where we can do the experiments in optimised conditions.

We also need a ‘Centre for Catalysis’ in Egypt where we can teach the new generation to develop sufficient skills to collaborate with the UK and other countries for advanced experiments and push the research forward. If research hubs could be set up across Africa, like the Catalysis labs at UCT, this would be fantastic and START could be an ideal vehicle to make this happen. Another route is through funding agencies like the British Council/Newton Funding which provide travel grants and other support for researchers in developing countries. 

To summarise the achievements of the GCRF START grant and what START means to me: I would describe it as “a great work for great value”, and all this despite massive setbacks caused by the Covid-19 pandemic.

START does great work that allows scientists from developing countries to gain knowledge and experience from leading scientists in the UK and to reciprocate, as my role shows. It does great work because it offers opportunities for us to work with scientists from all over the world on a level playing field. Ultimately, the greatest value from my perspective is that we work hard to provide (in a sustainable way) energy/electricity, medicines and many other applications for people who don’t have these fundamental things, enabling a better life for the future – what value is bigger or better than this?

Read more about the UN’s Sustainable Development Goals here

GCRF START Postdoctoral Research Fellow, Dr Khaled Mohammed, engaged in quantification and identification of reaction products using the GC (FID & TCD detectors) equipment at the University of Southampton, UK. Photo credit: Khaled Mohammed. ©Diamond Light Source

[1] [1] ACS Catal. 2020, 10(10), 5483–5492 (https://pubs.acs.org/doi/10.1021/acscatal.0c00414) – This work has significant implications for the upgrading of bioderived feedstocks, suggesting alternative ways for promoting selective transformations and reducing the reliance on precious metals. [2] Phys. Chem. Chem. Phys., 2020,22, 18774-18787 (https://pubs.rsc.org/en/content/articlelanding/2020/CP/D0CP00793E#!divAbstract) – This study demonstrates the complexity of mechanochemically prepared materials and through careful choice of characterisation methods how their properties can be understood. Synchrotron techniques, such as X-ray absorption spectroscopy (XAS), have multiple benefits, which aid the in-depth understanding of chemically important yet complex systems. [3] Nanoscale Adv., 2019,1, 2546-2552 (https://pubs.rsc.org/en/content/articlelanding/2019/NA/C9NA00159J#!divAbstract) –  Using state-of-the-art beamlines, this study demonstrates how X-ray absorption fine structure (XAFS) techniques are now able to provide accurate structural information on nano-sized colloidal Au solutions at μM concentrations. 

[2] ACS Catal. 2019, 9, 8, 7166–7178, Publication Date: June 28, 2019 https://doi.org/10.1021/acscatal.9b00685. Copyright © 2019 American Chemical Society

[3]  Author: Thulani M. Nyathi, Mohamed I. Fadlalla, Nico Fischer, Andrew P.E. York, Ezra J. Olivier, Emma K. Gibson, Peter P. Wells, Michael Claeys. Publication: Applied Catalysis B: Environmental. Publisher: Elsevier. Date: 15 November 2021. https://doi.org/10.1016/j.apcatb.2021.120450

My story: from Kenyan villager to international researcher tackling energy and climate challenges

“Abundant energy resources without adequate human resource and access to cutting edge infrastructure remains Africa’s contradiction and greatest challenge to harnessing its primary resources to useful forms. The GCRF START grant has been the vehicle towards the realisation of both, with Dr Francis Otieno being the success story to this initiative. His journey encompasses the germination to shoot culminating with the growth to a potentially giant tree visible in the horizon and useful in the vicinity” – Prof. Daniel Wamwangi, University of the Witwatersrand, South Africa.

It has been said that “The future belongs to those who believe in the beauty of their dreams”[1], but the truth is that so many of our dreams seem at first absolutely impossible. How do you dream of what you cannot visualise? Yet this is the story of a village boy in rural Kenya who knew nothing about experimental research laboratories or STEM, but years later became an international renewable energy researcher with a PhD in the START collaboration, with several papers published[2]. My name is Francis Otieno and I am telling this story to inspire school kids, emerging researchers, and everyone – your dreams are possible!

GCRF Dr Francis Otieno from the University of the Witwatersrand, South Africa, on a visit to the University of Oxford, UK.
Photo credit: Dr Francis Otieno. ©Diamond Light Source

From village schoolboy to PhD student – the beginnings of my renewable energy dream 

My story begins as I progressed into high school and experienced the heavy environmental pollution from the congested slums of Mathare in Nairobi, Kenya. Large numbers of smoking cars in the streets and continuous electricity blackouts were the norm, especially at the slightest onset of rains. When I look back, this was the start of my dream of making a difference to society and our communities, the start of a long journey in the quest for clean, sustainable renewable energy.

Today I am a GCRF START Postdoctoral Research Fellow (PDRF) in the field of Solar Energy research. I was born in rural part of Kenya called Seme Kadero, in Kisumu County, to a big polygamous family of four mothers and 27 children. I was number 20 in our family and my father, born in 1928, was quite passionate about his kids attending school but none before me made it to university. We were allowed to go to school in the mornings but had essential chores in the afternoons. We grew up grazing cattle barefoot and cultivating land in alternation with school hours – we couldn’t even afford to buy shoes.

My father saved some money for me to attend high school but soon realised this was sufficient only to buy school uniform and other items required for admission but not school fees. I had to make do with a new school uniform, including long trousers and shoes for the first time, which I wore at home while waiting for my father to raise the fees. I didn’t know what to read during those weeks, so after putting on my school uniform each day, I would go to the newspaper vendor, and ask to read all the daily newspapers with him, and then go home in the evening.

My passion was to realise my father’s dreams one day and return home with a title earned from studying. I wanted to be a teacher and contribute immensely to society. My Physics Teacher at Eastleigh High School in Nairobi really believed in me which made a huge difference. He gave me a project using angular inclination and the concept of rectilinear propagation of light to design a device that could be used to measure the height of any building/tree from a distance without having to climb it! This kickstarted my love of science and drove my research career ambition.   

I competed through the district and province and became the second best in the National Science Congress. The fire for research was then fully ignited, fuelled by the fact that I didn’t have a stable light source at night to study, in addition to the effects of environmental pollution. School and learning were vital.  To avoid being mugged for our precious school books, we would walk to and from school 6 km, rising early each morning and singing on the way back home to deter anyone from stealing our text books to sell on for drugs.

Childhood photo of Dr Francis Otieno (L) and his brother Jacktone Otieno (R) in their school uniforms at home in Kenya. ©Francis Otieno

My father had long retired from active business relying instead on peasant farming. Our tradition holds that our elder brothers help to cover school fees, which was a challenge as they were equally struggling to settle down in life. With all these hardships, my ambition was to improve performance at school which had back then only a 2-5% pass rate to public university. As a group of high school learners, we managed to turn this around and many secured a place at our public university where we could access government funding.

The best teacher teaches from the heart and not just the textbook, and this is what I intended when I chose a Bachelor of Education degree at Egerton University more than 100 miles northwest of Nairobi. I knew my heartfelt approach meant a lot to my father who has always urged me to do well and surpass any problems on the way. When I got my first Degree in Education teaching physics and mathematics, many of my pupils did well in my subjects. I am a proud teacher having seen them move into good careers using the physics and mathematics they had been taught.

My next thought was that the combination of research and teaching would be more impactful to society, so I enrolled for an MSc in Physics at the University of the Witwatersrand (Wits) in South Africa. Getting accepted on the course wasn’t easy, and I was rejected four times. Finally, in 2014, I joined Wits after resigning from my high school teaching job. This bold step would not have been possible without the encouragement of Prof. Daniel Wamwangi, Associate Professor in the School of Physics at Wits. I am forever grateful for the trust he had in me, the strong motivation he gave, and incredible guidance he has accorded me during my research journey at Wits.

Through his dedicated supervision I was able to successfully earn my MSc, within the time limit, and immediately enrol for a PhD, which I completed within a record time of 30 months together with an output of several publications. During my PhD journey, Prof. Daniel Wamwangi and Prof. Alex Quandt, Professor in Computational Physics in the School of Physics at Wits, formed the best team for supervision. From their immense expertise and with much hard work, I learnt so much within a record time and got exposure to advanced techniques, as well as collaborations within and beyond Africa.

From right: Professor Daniel Wamwangi, Dr Francis Otieno and Professor Alex Quandt at Francis’ PhD graduation at the University of the Witwatersrand, South Africa. Photo credit: Dr Francis Otieno. ©Diamond Light Source

I invited my then 92-year father to my graduation, and tears of joy flowed freely when he landed in Johannesburg for this happy event and throughout his three weeks stay with me in South Africa. It was his first time owning a passport and boarding an aeroplane and seeing his child graduate with the much-desired title of a Doctor of Philosophy. When my father returned to our village in Kenya, he would host sessions of storytelling about these experiences and remembers every tiny detail: his 20th child brought home his dream!

I told myself that although I was the first in the family to climb to this height of education, I would not be the last. Through this inspiration, four of my younger siblings have now earned their first degrees, and former students, friends and relatives have followed suit in South Africa and Kenya.

Dr Francis Otieno’s father, Mzee Christopher Otieno Oluoch wearing his son’s PhD graduation gown in 2018 at the University of the Witwatersrand, South Africa. ©Francis Otieno

GCRF START Postdoctoral Research Fellowship and participation in national and international science outreach events

Through hard work with good output, I was approached by my current host, Prof. Dave Billing in the Department of Chemistry at Wits, and he suggested that I apply for a Postdoc position funded by the GCRF START grant, even before my PhD thesis examination results were back. I was highly convinced that this was the best news ever, and indeed, being accepted by START would help my career and personal growth because I needed exposure outside of Africa as well as within, to move my research forward.

START was a real blessing at the right time when I truly needed it. The GCRF START grant funded my Postdoctoral Fellowship at Wits for two and a half years.  With START, I have been able to obtain lots of data results which have enabled me to publish in reputable journals. Being part of the START network has given me opportunities to collaborate with like-minded researchers at the UK’s University of Oxford, the University of Sheffield and the UK’s world-renowned national synchrotron – Diamond Light Source (Diamond). Through these interactions, I have learnt many new skills and exchanged knowledge and various perspectives.

In addition, back in South Africa and with support from the GCRF START grant to purchase the necessary kits, I participated in several community outreach programmes, including hosting an awareness and outreach activity for the 69th Lindau Nobel Laureate Meeting 2019 on Physics at the University of the Witwatersrand, which I attended in Germany. This was funded by The Academy of Science of South Africa (ASSAf), in partnership with the Department of Science and Technology (DST). The 2019 meeting – known by its Twitter hashtag #LINO19 – was dedicated to physics and was attended by 39 Nobel laureates and 580 young scientists from 89 countries. It was particularly meaningful for our South African contingent because South Africa hosted the International Day of Light that year. I also participated in the University of the Witwatersrand’s Yebo Gogga Exhibition and Focus Day, which assists young learners who need guidance into future careers such as in Physics.

Dr Francis Otieno in the laboratory undertaking D10 Grazing Incidence X-ray diffraction at the University of the Witwatersrand’s School of Chemistry, South Africa. This technique is used to determine the phases of thin films at the sample surface and multi-layer films. Photo credit: Francis Otieno. ©Diamond Light Source

Cleaner, cheaper energy sources through collaborations in cutting-edge advanced materials’ characterisation

Finding alternative cheaper energy sources using locally available materials such as organic polymers is the basis of my research. To provide clean renewable energy sources, the current market is dominated by silicon based solar cells which are high cost arising from the expense of extracting Silicon from its raw materials (sand) and due to their lower efficiency. Thin-film solar cells are known as second generation solar cell fabrication technologies to produce power electrical energy.

I focus on using nanoparticles technology such as plasmonics to realise efficient cheaper sources of energy and to find alternatives to silicon solar cells. My research interests are renewable energies and energy policy, and emerging solar technologies, with my focus under the GCRF START grant on materials’ characterisation, device fabrication and testing of thin films solar cells such as Organic Solar Cells (OSCs), perovskites, and dye sensitized solar cells. My project also explores ways to enhance the performance of these thin film devices through incorporation of nanoparticles technology and spectral conversion thin films with the ultimate goal of realising an efficient, cheaper source of solar energy and device-making for local and global markets

The GCRF START grant facilitated buying my research materials, and made and strengthened Africa-UK collaborations, with lab visits to the UK. This gave me exposure to cutting-edge opportunities and joint proposals to perform advanced materials characterisation such as Grazing Incidence Wide Angle X-ray Scattering (GIWAXs) at Diamond, and access to UK laboratories in the Materials Physics Group at the University of Sheffield with GCRF START Co-I, Professor David Lidzey, and to the Advanced Functional Materials and Devices Group (AFMD) with GCRF START Co-I, Professor Moritz Ried at the University of Oxford.

Dr Francis Otieno from the University of the Witwatersrand, South Africa, touring beamline I07 at the UK’s national synchrotron, Diamond Light Source. Photo Credit: Daniel Wamwangi. ©Diamond Light Source

The newly acquired National Thin-Film Cluster Facility for Advanced Functional Materials based at the University of Oxford is capable of being an epicentre for novel thin film development within the UK and beyond. This facility certainly places UK at the centre of the development of next-generation materials and devices for applications in energy, photonics and electronics. Access to this facility through my on-going collaboration with Oxford will certainly revolutionise my research prospects with increased potential of producing publications in collaboration with the AFMD group, namely Dr Pascal Kaienburg and Irfan Habib.

 In the Materials Physics Group at Sheffield University, Rachel Kilbride and Dr Joel Smith assisted me with carrying out GIWAXs on organic thin films. At Diamond, Dr Thomas Derrien guided me with joint beam time proposals enabling us to do measurements both at Diamond and the European Synchrotron Radiation Facility (ESRF). These collaborations and networks I aim to continue being involved in, and were made possible by Prof. Billing, who has much expertise in powder diffraction and energy materials across research networks within, and beyond Africa. I am always grateful for the faith he had to appoint me as a PDRF, and I have valued his immense support. Also, key is Prof. Wamwangi, who has been a great mentor in my research journey, from experimental techniques to manuscript preparation. As a result, I have contributed to several papers looking at solar cells materials and device-making instrumental to industries, working on improving the performance of solar cell devices highly needed in the global market.

Aerial view of the UK’s national synchrotron, Diamond Light Source, on the Harwell Science and Innovation Campus, UK. ©Diamond Light Source

We believe that the future of all technologies is ‘smart’ and for this reason, and Organic Solar Cells (OSCs) research is critical to realise efficient energy sources with advantages over current silicon solar cells, due to the abundance of materials and ability for scalable production processes that OSCs offer. Our aim is to contribute to the Sustainable Development Goals 7 (energy) and 3 (Climate) and the growing global demand for innovative, world class solar energy. Also, our research findings form the basis for teaching solar cell technology to undergraduate and postgraduate students as well as other Research Fellows back home.

Dr Francis Otieno with members of the START network from the University of the Witwatersrand (South Africa) on a visit to the University of Oxford in the UK. From front to back: Dr Francis Otieno, Professor Daniel Wamwangi and Professor Dave Billing; Right from front to the back: Professor Yasien Sayed, Dr Ramesh Pandian and Adam Shnier. Photo credit: Irfan Habib. ©Diamond Light Source

Inspiring hope, enabling others to dream – bringing my expertise back home

Although the journey is a long one, I am excited to have embarked on making a difference in the society through our research; and I am proud that my dream of impacting young people from rural areas like my own was realised when I became a teacher. To continue investing in developing others, I have started mentoring undergraduate and postgraduate students at the University of the Witwatersrand and now at Maseno University, Kenya, where I have been offered a job as a lecturer.

The GCRF START grant exposed me to new skills and advanced equipment, and through my successes and links to START, I was able receive the British Council Newton Travel Grant which will enable me to visit Oxford for a period of six weeks, currently planned for September 2021. This exposure together with much sought after skills and strong collaborations will be very useful to me as a young researcher looking forward to supervising postgraduate students back in Kenya, upon the completion of my Postdoctoral Fellowship.

As Kenyan bush-pilot, Beryl Markham[3], once said, “Africa is mystic; it is wild; it is a sweltering inferno; it is a photographer’s paradise, a hunter’s Valhalla, an escapist’s Utopia. It is what you will, and it withstands all interpretations.”  – one aspect of interpretation is that here, in my story and the story of START, hope does not disappoint!

Read more about the UN’s Sustainable Development Goals here

Dr Francis Otieno and his father, Mzee Christopher Otieno Oluoch, at Francis Otieno’s PhD graduation in 2018 at the University of the Witwatersrand, South Africa. ©Francis Otieno

[1] quote by Eleanor Roosevelt

[2] https://start-project.org/home/research/publications/ and https://scholar.google.com/citations?user=M9Ysk-4AAAAJ&hl=en accessed 20.7.2021

[3] https://www.historynet.com/remarkable-mrs-markham.htm accessed 20.7.2021

Development and optimisation of thin-film photovoltaic devices (solar cells) for sustainable solar energy

Scientists in the UK’s University of Sheffield’s Electronic and Photonic Molecular Materials Group (EPMM) work on the development and optimisation of thin-film photovoltaic devices (solar cells) for sustainable energy solutions. The advantage of these type of devices is that they can convert sunlight to electrical power with high efficiency, with such materials being easy and cheap to process, potentially allowing ‘sustainable’ solar cells to be manufactured at high volume and low cost. This is important given the rising global energy demand and need for electrification in remote, rural areas, particularly in Africa, where national grids are often over-constrained.

The EPMM Group, which collaborates with the GCRF START grant, focuses on two classes of materials: perovskites[1], [2] and polymer fullerene blends. Industry standard silicon solar cells require very high temperature processing and expensive controlled environments (clean rooms) for their manufacture, whereas hybrid-perovskites solar can be fabricated at low temperatures using liquid-based processing which reduces costs and makes their production easily scalable. However, one of the biggest challenges with these hybrid-perovskites is their reduced stability compared to silicon. The Group is therefore investigating these materials to understand how best they can be optimised for the next generation of solar energy devices.

Fig 1. This figure shows both small and large area perovskite PV devices fabricated by spray coating. The figure also shows a SEM cross-sectional image through a typical device. Part (a) shows a photograph of small and large-area fully spray-coated perovskite solar cells. Parts (b,c) show a cross-sectional SEM image of complete devices incorporating a spray-cast perovskite layer. The device in part (b) utilises spin cast SnO2 and spiro-OMeTAD layers whereas the device in part (c) is fully spray-coated. Source: Bishop, J.E., Read, C.D., Smith, J.A. et al. Fully Spray-Coated Triple-Cation Perovskite Solar Cells. Sci Rep 10, 6610 (2020). https://doi.org/10.1038/s41598-020-63674-5.

Investigating affordable energy solutions with the GCRF START grant

In their research, the EPMM scientists have benefitted from the GCRF START grant, enabling them to get involved in new international collaborations as well as access the UK’s national synchrotron, Diamond Light Source (Diamond), where they use synchrotron techniques such as X-ray scattering to research halide perovskites, a potential material for the next generation of low-cost photovoltaics.

“Using Diamond allows us to explore the structure of these materials at length-scales corresponding to atomic and molecular bonds, we have found that understanding the structure of these materials is absolutely critical in developing our understanding of how they ‘work’ in devices. Ultimately, this understanding helps in developing new materials or new ways to process existing materials to get optimum performance (efficiency) out of our solar cells.”

Prof. David Lidzey, GCRF START Co-I and Director of the EPMM Group
From left to right: Adam Shnier from the Energy Materials Research Group at the University of the Witwatersrand, South Africa, and Rachel Kilbride, Joel Smith and Mary O’Kane from the Electronic and Photonic Molecular Materials Group at the University of Sheffield, UK. The scientists are conducting wide-angle X-ray scattering measurements at the UK’s national synchrotron Diamond Light Source (Diamond). The students are using one of Diamond’s 2D X-ray detectors to monitor in-situ crystallisation and degradation processes with perovskite thin film samples held in an environmental chamber. Photo credit: Onkar Game. ©University of Sheffield / EPMM Group

The GCRF START grant has also funded Dr Onkar Game’s one-year Postdoctoral position in the EPMM Group during which time he has both undertaken his own experiments on perovskites and worked very closely with various PhD students in the Group. Prof. Lidzey reports that Dr Game’s input has been invaluable, this flexible work-pattern maximising the amount of research using the funding available.

“The GCRF START grant provided me a unique opportunity to make use of world class structural characterisation facilities at Diamond” says Dr Game. “Working with PhD student Joel Smith, we utilised the in-situ Grazing Incidence Wide Angle X-ray Scattering (GIWAXS) facility at the I22 beamline in Diamond to identify the factors affecting the degradation of perovskite crystal commonly used in perovskite-PV devices[3]. This helped us to tune the composition of perovskite crystal to make it more stable towards moisture and light induced degradation. I also enjoyed setting up the in-situ measurements with Joel on understanding of solvent-induced liquification and crystallisation of perovskite using GIWAXS on Diamond’s I07 beamline,” Dr Game adds.  

From left to right: Prof. David Lidzey and Dr Onkar Game from the University of Sheffield’s EPMM Group, UK. The scientists are investigating perovskite degradation using an environmental chamber and 2D X-ray detector on the I07 beamline at the UK’s national synchrotron Diamond Light Source. Photo credit: Joel Smith. ©University of Sheffield / EPMM Group

Collaborative research on Perovskites: the effects of composition and temperature

Dr Claire Greenland completed her PhD in the EPMM Group supervised by Prof. Lidzey. She has been working on perovskites and has been particularly interested in how the structure of such materials are affected by their composition and local temperature. This work was done in close collaboration through the GCRF START network with the Energy Materials Research Group at the University of the Witwatersrand (Wits), South Africa, led by GCRF START Co-I, Prof. Dave Billing. In this research, Claire studied one type of popular perovskite called a ‘mixed cation’ perovskite, and used X-ray scattering to characterise the structure of the perovskite as it was cooled down to very low temperature (-190 °C). She also measured the ability of the perovskite to absorb and emit light over the same temperature range. In these studies, Claire was looking for changes in the crystal-phase as the temperature was changed.

Understanding such processes is important, as the temperature at which some phase changes occur are within the expected operational temperature of the solar cell and understanding the effect on the properties of the materials in the solar cell forms a critical part of the understanding of how such materials (and devices) work.

“Interestingly, the structure of the perovskite crystal is not fixed, but can vary as a function of temperature, being ‘cubic’ at room temperature and starting to change to a ‘tetragonal’ phase around -13 °C, with a second low-temperature phase identified at -180 °C,” Prof. Lidzey explains. “Through careful analysis, these changes in crystal structure could be correlated with changes in the optical properties of the perovskite.”

This research was supported with assistance from Wits University scientist, Adam Shnier. Adam met members of the Sheffield team at a GCRF START meeting in 2018, hosted by the Energy Materials Research Group at Wits.

“Adam Shnier provided us invaluable support in the analysis of the X-ray scattering data, allowing us to understand how the crystal structure changed with temperature,” Prof. Lidzey says.With support from the GCRF START grant, Adam was able to travel to the UK in 2019 and assist us in some scattering experiments performed at Diamond and became an important part of the team.”  

“At the 2018 GCRF START meeting, I met a PhD student, Joel Smith, from the University of Sheffield who works on the same type of materials,” says Adam. “Joel and his colleagues are experienced at making high quality, efficient devices; while at Wits, we are experienced in making other materials that can be used for these devices and studying their crystal structures. As the 2019 GCRF START meeting was being held in the UK, we planned a research visit where I would spend a week working with Joel and his colleague Dr Onkar Game in Prof. David Lidzey’s laboratory at Sheffield. The purpose was to share technical knowledge. They were more than happy to share their experiences with these materials which instilled me with a plenty of ideas and information to share with my colleagues at home in South Africa.”

Adam Shnier from the Energy Materials Research Group at the University of the Witwatersrand, South Africa, visiting the UK’s national synchrotron, Diamond Light Source. Photo credit: Joel Smith. ©University of Sheffield / EPMM Group

The research was published in January 2020[4] and formed a very important part of Claire’s PhD thesis. Claire has since passed her PhD viva and has come back to Sheffield in the position of ‘University teacher’. While she is not currently working on perovskites, her knowledge of materials physics and experience in understanding complex phenomena are proving invaluable in teaching electromagnetism to 1st year undergraduate students and will also be useful in the 2nd year lab experiments that she is developing and running, says Prof. Lidzey.

‘The GCRF START collaboration enabled me to collaborate with academics from Wits University in South Africa, which greatly enriched my work due to their expertise in X-ray diffraction and crystal structure,” Claire explains.  “I collaborated mainly with Adam Shnier, who was able to computationally model the X-ray diffraction data taken at a range of temperatures on mixed cation perovskites. This modelling revealed the temperature dependence of a variety of crystal parameters, which not only allowed us to identify phase transitions in these materials but also to correlate crystal structure with photoluminescence properties.”

“I really enjoyed working with Adam, and his insight on all things related to crystal structure and phase was invaluable to my work,” Claire adds. “These studies shed light on the fundamental properties of perovskites and how these vary as a function of temperature – such studies are a key part of solar cell optimisation, because real world solar cells must operate under a wide range of temperatures. So, it’s really cool to know that this project was part of the push towards cheap and efficient solar cell materials, which are an essential part of tackling climate change.”  

Dr Claire Greenland from the University of Sheffield’s Electronic and Photonic Molecular Materials Group, UK. ©University of Sheffield / EPMM Group

Perovskite ‘healing’ for high-speed manufacture processes

PhD student Joel Smith has also been working on perovskites. Here, however, he has been interested perovskite recrystallisation processes using solvent molecules. In this process, a perovskite film is exposed to a solvent gas, with this exposure causing the solid perovskite film to melt into a different solid or liquid form. Once the gas is removed or when heated, this material crystallises back into a ‘healed’ perovskite. The advantage of this process is that the quality of the perovskite film can be substantially improved. Practically, this could be used to improve the quality of perovskite films deposited in a high-speed manufacture process such as spray coating.

The first part of this work was led by Dr Onkar Game and investigated how treatment with one type of solvent had some unexpected effects on the perovskite film microstructure. This included measurements on thin films at Diamond to understand how these changes in microstructure affected the perovskite’s ability to withstand different challenging environments3. As part of his PhD, Joel undertook experiments at Diamond where he used X-ray scattering to monitor the very rapid changes in the structure of the perovskite film as it turned into a liquid and then back into the perovskite.

“Here we were able to resolve crystal structures of new intermediate compounds that formed in the liquid, and we could evidence the improvement in crystal structure caused by the healing process,” explains Prof. Lidzey, “Importantly, we also showed that this process could be enhanced by changing the temperature at which healing took place.”

Joel is currently writing a paper on this work which has formed part of his PhD thesis. He is set to start his Postdoctoral research in Prof. Henry Snaith’s group at the University of Oxford, working on advanced perovskite solar cell devices.

“Bringing together expertise from our different institutions in the UK and Africa through collaborating with the GCRF START grant has allowed us to investigate the crystallisation behaviour and stability of perovskites in new ways at Diamond Light Source,” says Joel. “More generally, we have been able to assist each other in fabricating, characterising and understanding these materials by sharing experience and facilities. The wider START community has been valuable as a mutually supportive network for us to develop as independent researchers, and most importantly, to grow the synchrotron research community in Africa.”

Joel Smith from the University of Sheffield’s Electronic and Photonic Molecular Materials Group, UK. Photo credit: Onkar Game. ©University of Sheffield / EPMM Group

Commenting on the need for affordable, renewable energy solutions in Africa and the importance of collaboration to tackle global energy challenges, Prof. Billing said,

The synergy in GCRF START collaborations of having people from different backgrounds tackle a problem makes the solution more robust. Creativity is important to most Africans, and we need to be involved in these creative solutions. Also, if you co-develop through collaboration, you have a sense of ownership which is what we set out to do through the GCRF START grant.”

“Everything costs energy, fundamentally,” Prof. Billing adds. “Silicon uses a lot of energy in its making to make solar cells so I think the best we can do as humans is look at remediation and balance. The GCRF START grant asks us to consider questions in our research around the global challenges like: am I using components that are sustainable? Are we using elements which are abundant, affordable, and environmentally compatible? If you think about a rural village which is cooking using wood charcoal, they are energy poor and lighting will be paraffin or candles. If you can find a cheap source of energy there and you can bring in lighting, that is life changing!”

Traditional rondavel house in a rural South African village. Photo Credit: Rebekka Stredwick. ©Diamond Light Source
Adam Shnier at the University of the Witwatersrand taken in front of a Bruker D8 diffractometer which he uses in the analysis of thin film materials. Photo credit: Adam Shnier. ©Diamond Light Source

Read more about the Sustainable Development Goals for Energy (SDG 7).

[1] Here, “perovskite” is a name for a class of crystalline material, and there are many different combinations of starting materials that can be used to make a perovskite. Some of these materials absorb sunlight more efficiently, and others have greater environmental stability (both important characteristics for practical applications of solar cells).

[2] Bishop, J.E., Read, C.D., Smith, J.A. et al. Fully Spray-Coated Triple-Cation Perovskite Solar Cells. Sci Rep 10, 6610 (2020). https://doi.org/10.1038/s41598-020-63674-5. This work demonstrates the possibility for spray-coating to fabricate high efficiency and low-cost perovskite solar cells at speed.

[3] Onkar S. Game, Joel A. Smith et al.  Solvent vapour annealing of methylammonium lead halide perovskite: what’s the catch? J. Mater. Chem. A, 8, 2020, 10943-10956 DOI: 10.1039/D0TA03023F 

[4] Greenland, Claire, Adam Shnier, Sai K. Rajendran, Joel A. Smith, Onkar S. Game, Daniel Wamwangi, Graham A. Turnbull, Ifor DW Samuel, David G. Billing, and David G. Lidzey. “Correlating Phase Behavior with Photophysical Properties in Mixed‐Cation Mixed‐Halide Perovskite Thin Films.” Advanced Energy Materials 10, no. 4 (2020): 1901350 (https://doi.org/10.1002/aenm.201901350)