Flexible Solar Cells Based on Chalcogenides

Abstract

Flexible solar cells have attracted enormous attention owing to the possibility of reducing the weight of solar modules and developing a wide variety of applications. Among others, chalcogenide-based flexible solar cells offer great promise to achieve efficiencies comparable to those on rigid substrates. Record efficiency of 20.8% was reported in 2019 for CIGS solar cells on a polyimide substrate. Reaching such a high-performance level on the flexible substrate has closed the gap with the matured Si wafer-based photovoltaic technology. Other chalcogenides, such as CdTe, CZTSSe, and Sb2Se3 have also shown their potential to reach efficiencies as high as achieved with rigid substrates. A variety of substrates, including metallic foils, polymer films, flexible glass, paper such as cellulose papers, and plain white copying papers, have been explored for chalcogenide-based flexible devices. Despite decent performance and great viability shown by flexible chalcogenide solar cells, several issues still need to be addressed to transfer laboratory-scale results into industrial production of highly efficient flexible solar modules. This chapter discusses in detail the progress and development of flexible chalcogenide solar cells on different flexible substrates, challenges imposed by fabrication processes along with prospects, and strategies for further advancements.