Centre for Sustainable Chemical Technologies

Scientists and engineers working together for a sustainable future

Tagged: Photovoltaics

Hybrid Organic Photovoltaics Conference, Swansea, 2016

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📥  Comment, Seminars & Conferences

This post was contributed by Oli Weber following his attendance at the Hybrid Organic Photovoltaics Conference (28 June - 1 July 2016).


Recently Dom Ferdani (cohort ’14) and I took a trip to the south coast of Wales to attend the 2016 Hybrid Organic Photovoltaics Conference (HOPV 16). The venue was Swansea’s brand new Bay Campus, a huge new development of university buildings sited right by the beach of Swansea Bay. On the first conference day we were met by serious weather blowing in from the sea, leaving delegates from warmer climes wondering what manner of people could be mad enough to inhabit such a cold, damp land. Bay Campus is also the new home to SPECIFIC, the conference hosts, whose mandate is to span the space between academia and industry to develop materials that turn buildings into power stations using functional coatings. Building integrated photovoltaics (BIPVs) are one of the families of technologies developed at SPECIFIC. These rely on thin, lightweight, flexible designs and manufacturing methods, such as printing, that scale up well. Organic semiconductors, dye sensitised solar cells, CIGS and CZTS are all under research and development, however the technology that has come to dominate the research focus for this conference is hybrid perovskite solar cells.

Dom and Oli in Swansea

Dom and Oli in Swansea

Hybrid perovskites combine the properties of some of the highest quality known semiconductors, such as GaAs, with the solution processability of organic materials. This means that the solar cells could be manufactured at low cost, while still displaying the high efficiency of the best inorganic thin films. Unfortunately the hybrid perovskites are not very chemically stable and are easily attacked and degraded by water. Some of the typical device layers used in perovskite cells may also be contributing to the degradation, so it is still difficult to assess whether these materials will be intrinsically stable, over a 25 year lifetime, if they are properly encapsulated as protection from the environment. It was encouraging to see stability data discussed during the research presentations, particularly in the talk by Professor Mike McGehee of Stanford, whose group is developing semi-transparent perovskite top cells to include directly above standard silicon modules to make a more efficient tandem stack.

Other highlights for me personally were the advanced printing techniques run by SPECIFIC researchers on the day before the conference commenced, when we learnt about the pitfalls that await between laboratory scale work and development of cells suitable for bulk manufacturing at large scale. Professor Laura Herz of Oxford Physics gave an excellent presentation on the amount that can be learnt about charge carrier dynamics within perovskite semiconductors using terahertz photoconductivity and photoluminescence measurements. From the University of Bath, Professor Aron Walsh and Dr Petra Cameron both presented recent research results.

Overshadowing the whole conference was the spectre of Brexit. Many people had learnt the referendum result just before setting out to Swansea. Swansea is one of the areas of the UK that voted to leave despite receiving extensive regeneration funding from the EU; SPECIFIC itself is part EU funded. The research groups present were drawn from diverse international backgrounds and many of the research collaborations, already in progress or spawned during the conference, span the EU and further afield. One thing for certain is that the scientific community will continue to find ways to maintain their international networks and friendships whatever the political landscape. From my point of view (and that of many I spoke to) it’s frankly embarrassing that the referendum campaign was fought, won and lost on the basis of fear, lies and bigotry, drowning out all vestiges of the rational debate scientists thrive on. For a country priding itself on freedom and enterprise, we cannot claim to have a healthy political or media culture.

Sitting on the terrace of the conference hall, the beach ahead of me, it is impossible to ignore the juxtaposition of frenetic scientific activity behind me, as brilliant people from every part of the world work to develop clean energy sources for the future, with the EU and Welsh flags taut in the sea breeze just in front and, visible further along the coast, Port Talbot steelworks, in the news as 4,000 people wait on tenterhooks to hear if their livelihoods will disappear. Swansea is an area already hard hit by disappearing traditional industries, on the sharp end of globalised trade. The referendum vote has already delayed and could wreck buyout bids to retain the steelworks, with 69% of Welsh steel exported to the EU. Projects like SPECIFIC serve a dual purpose, for research and as attempts to sow new seeds of industrial activity for clean technologies for the twenty first century. If and when the UK regains political leadership, it will be up to UK government to prove it can support these activities as well as the EU did, or risk watching top researchers and research, as on display at HOPV, move elsewhere.


Oli is Cohort '13 of the CSCT, studying towards his PhD on "Optimizing energy harvesting processes in metal halide photovoltaics" with Professor Mark Weller and Professor Chris Bowen.

 

Science by the Sea: APS Meeting 2016 and Visiting Duke University

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📥  Internships & visits, Seminars & Conferences

The following blog is written by Suzy Wallace.


This year the American Physical Society (APS) March Meeting was held in Baltimore, Maryland, USA from the 14th to 18th of March. I was fortunate enough to attend a tutorial day before the conference and to present my research on the potential new solar absorber material for solar cells, CZTS (Copper zinc tin sulphide).

This particular conference is amongst the largest physics conferences held each year with almost 10,000 attendees and around 50 or 60 symposia occurring at any given time with most talks only lasting ten minutes– so there was always potentially a lot to learn and you certainly were not short of things to do! The conference organisers even design a phone app for the conference to help you keep track of your schedule so that you don’t miss anything!  In addition to that there were a number of other events going on during the conference (such as the ‘rock n roll physics sing-a-long’ one evening) and also a lunch time special where you sign up to have a packed lunch with an expert in a particular field and a small number of other interested students. This was a great opportunity to discuss and get some advice on your research and career. It was also a great opportunity to ask questions to further your own understanding without having the slightly daunting situation of asking a potentially silly question in front of a very big audience!

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Baltimore was certainly an interesting city with lots of character to it! There seemed to be an interesting mixture of very artsy places and then much more urban areas. Then of course the harbour was beautiful and the seafood there was very good. I tried oysters for the first time there, conveniently during ‘oyster happy hour’ when they were $1 each!

After the conference in Baltimore I hopped over a state to head to Duke University in North Carolina to spend two weeks starting a new project with my international supervisor, Dr Volker Blum from the Department of Mechanical Engineering and Materials Science and his group, the "Ab initio materials simulations" group. The students and postdoctoral researchers in the group develop an atomistic simulation code (FHI-aims), which can be used to predict the properties of materials for various applications. In my case, it is the properties of a material that could indicate the potential to make a good solar cell that I’m looking for. Interacting with people who develop the methods you use is such a great learning experience, it also happened that there were a number of interesting guest speakers visiting the university while I was there so I got to attend even more talks!

As well as discussing simulating materials on computers, we also visited the Outer Banks off the coast of North Carolina at the weekend as a research group. This was such a beautiful coastal area with some amazing sand dunes, lots of light houses and this was also where the Wright brother’s first flight in a controlled, powered vehicle took place (presumably due to the soft landing space provided by the sand dunes!). There was certainly a lot to see at the Outer Banks for such a small strip of land and of course where better to discuss calculating a material’s properties using the many-electron wavefunction than at the beach after all!

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Duke University, Durham, North Carolina, USA (left) and the Outer Banks, North Carolina, USA (centre and right, although it wasn’t quite as sunny for us as it is in the far right photo!).

Suzy is working towards her PhD on 'Overcoming the efficiency bottleneck of metal sulfide solar cells' with Professor Aron Walsh, Professor Chris Bowen and Professor Mark Weller.

 

October 2011 Symposium: "Photovoltaics— the future is bright"

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📥  Seminars & Conferences

The Centre for Sustainable Chemical Technologies continued its on-going tradition of hosting world-leading symposia last week with “Photovoltaics— the future is bright”.

Over 100 registered attendees took part in the event, including staff and students from various departments of the University of Bath and even a few external visitors. Speakers ranged from theoretical chemists to process engineers from both industry and academia, providing insight into the scientific challenges and opportunities in one of the most active fields of science today.

The University of Bath’s very own Professor Laurie Peter wrapped up the day by returning focus to the principal theme of the centre: sustainability. Many issues experienced in the field were discussed, including the availability of elements and energy payback times, providing ample food for thought over delicious nibbles and drinks!

Special thanks are extended to the students who organised the event as well as all the speakers for making it such a success.