Theoretical investigation of electronic and optical properties of the CuIn1-x GaxSe2: Ab initio calculation

Abstract

The controversial materials using in solar cell, Copper-Indium-Gallium-Selenide (CIGS) is highly favorable for solar power systems, due to its large optical absorption coefficient, long term stability, low cost and high conversion efficiency. The electronic and optical properties of CuIn1-xGaxSe2, are calculated using the density functional theory (DFT) implemented on Wien2k code with GGA + mBJ approximation, for different concentrations of Ga. Moreover, we compare the physical proprieties between CuInSe2 CuIn0.75Ga0.25Se2, CuIn0.50Ga0.50Se2, CuIn0.25Ga0.75Se2, CuGaSe2 in the wavelength range. According to the picks obtained, we can affirm that the CIGS is a good candidate for photovoltaic applications, especially the CuIn0.75Ga0.25Se2 because it’s much more absorptive and productive, with an optical absorption that reaches 104 in visible range.