Band Gap Dependence on Cation Disorder in ZnSnN2 Solar Absorber

© 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.The band gap of earth-abundant ZnSnN2 can be tuned between 1 and 2 eV by varying the growth conditions and resulting cation disorder. The optical absorption edges and carrier densities fall between model curves for cation-ordered orthorhombic and disordered wurtzite ZnSnN2. Hard X-ray photoemission spectra suggest different degrees of cation disorder from comparison with hybrid DFT-calculated densities of states.