Facile colloidal synthesis of quinary CuIn1−xGax(SySe1−y)2 (CIGSSe) nanocrystal inks with tunable band gaps for use in low-cost photovoltaics

Abstract

We report, for the first time, colloidal synthesis of quinary CuIn1−xGax(SySe1−y)2 (CIGSSe) nanocrystals across the entire composition range (x,y) = 0 to 1 with band gaps tunable in the range of 0.98 to 2.40 eV by facile chemical synthesis. As a proof-of-concept, thin-film solar cells made by using the CIGSSe nanocrystal inks as an absorber layer precursor exhibited an efficiency over 1% under AM 1.5 illumination.