Facile solvothermal way to synthesize CuIn0.7Ga0.3S2 nanocrystals and their application in low-cost photovoltaic device

• Metastable zincblende CuIn0.7Ga0.3S2 were prepared by a facile solvothermal method.
• The CuIn0.7Ga0.3S2 was directly applied as absorber layer in CIGS solar cells.
• The Zincblende CuIn0.7Ga0.3S2 can be potentially used in thin film solar cells.

Facile solvothermal way to synthesize quaternary CuIn0.7Ga0.3S2 (CIGS) semiconductor nanocrystals has been reported here. X-ray powder diffraction, energy dispersive X-ray spectrometry, transmission electron microscopy, X-Ray photoelectron spectroscopy and UV–Vis spectrometry were used to characterize CIGS nanocrystals. As-synthesized CIGS nanocrystals ink was used to prepare absorber layer. After selenization and device fabrication, the CIGS solar cells exhibited 0.36% power conversion efficiency under 1.5 AM illumination.