Defect Tolerance: Perfect Imperfection (UCL Research Poster Competition 2021)

My entry to the 2021 UCL Research Poster Competition.
YouTube talk here: https://youtu.be/XL17v5YxlKU

If you're interested in this work, please check out our open-access review on perovskite-inspired materials and defect tolerance here:
https://iopscience.iop.org/article/10.1088/1361-6528/abcf6d

For other research articles see:
https://bit.ly/3pBMxOG

For other talks on YouTube see:
https://bit.ly/2U5YgLf

Transcript

1. Defect Tolerance: Perfect Imperfection Seán Kavanagh Even though these atomic ‘mistakes’ may occur only once for every billion normal atoms, like DNA, they can significantly alter the resulting macroscopic properties. Just as a single genetic mutation can change your eye colour from brown to blue, a tiny amount of defects can kill device performance in a range of important technologies, such as solar cells, batteries in electric vehicles, pacemakers and iPhones, or even LEDs in your TV and phone screens. Scan me with your phone camera for a 4 minute YouTube talk on this work! Or search/click: youtu.be/H8cvJfZq8S8 @Kavanagh_Sean_ sean.kavanagh.19@ucl.ac.uk a Supervisor: Prof David Scanlon (Chemistry) Captions a. Like genetic mutations in DNA, rare but omnipresent ‘imperfections’ in materials can cause major overall changes, such as preventing the efficient conversion of sunlight to electricity in solar cells. b. Outline of a typical high-throughput screening investigation, with a large input material search space assessed using chemical rules and quantum mechanical calculations to predict material properties and performance. From this, a small selection of promising defect-tolerant candidates are obtained, for further experimental verification and development in low-cost high-efficiency devices. Like the rare, random mutations in DNA which facilitate evolution, all materials contain faults in the arrangement of their atoms, known as ‘defects’. These wonder materials could revolutionise the energy sector, making the dream of cheap renewable energy a reality. In our lab, we use quantum mechanical calculations to understand the atomic properties of these materials and their defects, before then leveraging this understanding to search unexplored chemical space for materials that fit this criteria. Given that there are trillions of compounds and materials yet to be discovered, we are hopeful that we will soon find the ‘needle in the haystack’ that exhibits defect tolerance and is stable, non-toxic and earth-abundant. The future is bright for solar technology! Recently, an exciting new class of ‘defect-tolerant’ materials has emerged – which retain high device efficiencies despite large concentrations of defects, allowing extremely cheap manufacturing costs. b A missing atom here, an atom in the wrong place there. Check out our recent review paper on this topic: Huang, Y.-T.; Kavanagh, S. R.; Scanlon, D. O.; Walsh, A.; Hoye, R. L. Z. Perovskite-Inspired Materials for Photovoltaics and beyond; from Design to Devices. Nanotechnology 2021, 32 (13), 132004. doi.org/10.1088/1361-6528/abcf6d.