Abstract

Organic-inorganic halide perovskites (OHPs) are the rising stars of photovoltaic (PV) and optoelectronic research [1]. With power conversion efficiencies surging from 3.8% to 22.7% [2,3] in the last 9 years, perovskite solar cells may form fierce competition to the incumbent silicon-based technology in the coming years. OHP materials possess many of the properties needed for efficient solar energy conversion including strong absorption coefficients, high carrier mobility and a tuneable direct bandgap [1]. Solution-processed perovskite inks are deposited as polycrystalline thin films using facile methods (spin coating, spray coating, printing), at low temperature. This ease of manufacturing provides a pathway to large-scale printable cells.

Nevertheless, the performance of state-of-the-art OHP solar cells is still limited by defects, which introduce parasitic non-radiative recombination (NRR) pathways through which energised charges lose their energy to heat [4]. This premature recombination of charge restrains the open-circuit voltage, and hence the efficiency of devices.

After an introduction to perovskite materials, I will discuss current research including the cutting edge science being investigated at the Cavendish Laboratory. Finally, I will explore the potential of perovskite PV in the context of future global energy needs.

[1] Stranks, S. D. & Snaith, H. J. Metal-halide perovskites for photovoltaic and light-emitting devices. Nature Nanotechnology 10, 391-402 (2015). [2] Kojima, A., Teshima, K., Shirai, Y. and Miyasaka, T. Organometal Halide Perovskites as Visible-Light Sensitizers for Photovoltaic Cells. J. Am. Chem. Soc. 131, 6050-6051 (2009). [3] Green, M. A. et al. Solar cell efficiency tables (version 51). Progress in Photovoltaics: Research and Applications 26, 3-12 (2018). [4] Stranks, S. D. Nonradiative Losses in Metal Halide Perovskites. ACS Energy Letters 2, 1515-1525 (2017).