Structural and optical properties of CuIn1-xGaxSe2 nanoparticles synthesized by solvothermal route

CuIn1-xGaxSe2 (CIGS) nanoparticles have been successfully fabricated by using a relatively simple and easy handling solvothermal process in the solvent of N, N dimethylformamide (DMF). A probable formation mechanism of chalcopyrite quaternary semiconductor nanoparticles is proposed. Structural, morphological and optical properties of prepared nanoparticles CIGS (x = 0, 0.3, 0.6, 0.8 and 1) were analyzed. The synthesized product is of ordered chalcopyrite structure, with the particle size in the range of 15-25 nm Cu2Se secondary phases was detected by XRD for the sample with x = 1, which is also affirmed by Raman spectra. Cathodoluminescence measurements allowed us to observe a high emission which can be attributed to a band to band transition, and the possible energy gap was discussed. The absorption spectra showed strong absorption in the entire visible light to near-infrared region. All results suggested that the as-prepared CIGS nanoparticles were good light absorber layer material for thin film solar cell applications. (C) 2015 Elsevier B.V. All rights reserved.