Triple-Source Co-evaporation of lead-free Cu2AgBiI6 for Use in Tandem Solar Cells
Benjamin Putland a, Marcello Righetto a, Harry Sansom a, Markus Fischer b, Laura Herz a, Henry Snaith a
a Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU, United Kingdom
b Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich, Switzerland.
International Conference on Hybrid and Organic Photovoltaics
Proceedings of International Conference on Hybrid and Organic Photovoltaics (HOPV22)
València, Spain, 2022 May 19th - 25th
Organizers: Pablo Docampo, Eva Unger and Elizabeth Gibson
Oral, Benjamin Putland, presentation 298
Publication date: 20th April 2022

Realising utility-scale multi-junction perovskite solar cells would represent a fundamental shift in the PV landscape by reducing the levelised cost of electricity and accelerating the global transition to a greener future. As such, developing 2 eV absorber materials for use as a top cell absorber in triple junction cells is of vital importance. Whilst many of the material requirements can readily be met by compositionally tuning the halide ratio in traditional hybrid perovskite solar cells, concerns remain over the toxicity of lead, and light-induced phase segregation. In this work, we present a novel alternative, Cu2AgBiI6, which overcomes these challenges. For the first time, we demonstrate that Cu2AgBiI6 can be thermally evaporated using triple-source co-evaporation. We present a thorough characterisation of its structural and optoelectronic properties, and show annealing films post-deposition in ambient air or I2-vapor greatly improves optoelectronic properties through enhanced photoluminescence and charge carrier lifetime. However, we find that improved optoelectronic properties do not necessarily result in more efficient devices. By correlating structural, compositional, optoelectronic, and device data, we shed new light on this novel material, and provide promising routes to further efficiency gains.

We use our own and third party cookies for analysing and measuring usage of our website to improve our services. If you continue browsing, we consider accepting its use. You can check our Cookies Policy in which you will also find how to configure your web browser for the use of cookies. More info