Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV23)
Publication date: 30th March 2023
In recent decade, lead halide perovskites (APbX3, with A = Cs, FA, CH3NH3 and X = Cl, Br, I) have caused great interest in optoelectronic devices, such as solar cells, photodetectors and LEDs, owing to their unique optical and electronic properties. Especially for photovoltaic devices, the recorded efficiency of single junction perovskite solar cell has reached 25.8%,1 which is comparable with Si solar cells. However, the toxicity of lead and low long-term stability of lead halide perovskites are the key issues that impede rapid commercialisation. Therefore, it is essential to develop highly efficient and stable lead-free halide perovskite solar cells.
Among those lead-free alternatives, Sn-based and Bi-based are considered as most promising lead-free perovskites for optoelectronic applications. [1] Unfortunately, Sn2+-based perovskites suffer from serious instability against oxidation. Bi3+ shows better environmental stability than Sn2+, while Bi-based perovskites have higher challenge to get high-quality thin films with good charge transport properties. The performance of lead-free perovskite solar cells is far behind that of lead-containing counterparts. Up to date, the record efficiency of lead-free perovskite solar cell has only reached 14.81% for Sn-based [2] and 6.37% for Bi-based [3], respectively. My research focuses on a deeper understanding of the crystallization dynamics and charge transport properties of Sn-based and Bi-based lead-free perovskites and developing highly efficient lead-free perovskite solar cells and photodetectors. In my talk, I will present our recent research results and talk about some strategies to improve the thin-film quality and charge transport properties, in the aid of achieving good optoelectronic performance.