Improved performance of solar cells using chemically synthesized SnSe nanosheets as light absorption layers

Abstract

We report the method to fabricate SnSe nanosheet (NSs) coated solar cells with very high performance compared to similar solar cells previously reported using chemically synthesized SnSe nanocrystals. SnSe NSs do not contain toxic metals and are promising materials for the top layer of tandem solar cells. SnSe NSs synthesized using the hot injection method were not suitable for coating as a light absorption layer because of their nonuniform size and tendency to aggregate. The one-pot synthesis produced SnSe NSs with uniform size, making them suitable for fabricating flat and homogeneous films when mixed with conductive polymers. The photoelectric conversion efficiency (PCE) of 4.8% was achieved using films with a sheet coverage of 14.2% of SnSe NSs. The PCE value was nearly two orders of magnitude higher than that of previous similar SnSe-coated solar cells. SnSe NSs coated films, which can be easily produced unlike vapor phase methods, were shown to have the potential to make an important contribution to the field of photovoltaic power generation.