Synthesis and characterization of flower-like CuIn1−xGaxS2 (x = 0.3) microspheres

We report the formation and characterization of the flower-like CuIn1−xGaxS2 (x = 0.3) microspheres using CuCl2·2H2O, GaCl3, InCl3 and l-cystine in the mixed solvent of ethylene glycol and distilled water (1:2, v/v) at 200 °C for 24 h. XRD results indicated that the CuIn0.7Ga0.3S2 nanostructures have a (1 1 2) preferred orientation. The EDS and XPS analyses of the sample revealed that Cu, In, Ga and S were present in an atomic ratio of approximately 1:0.7:0.3:2. FESEM and TEM images showed that the product was microspheres, consisting of nanoplates with the thickness of about 20 nm. The optical properties were investigated by ultraviolet–visible (UV–vis) absorption spectroscopy and Raman spectroscopy. UV–vis absorption spectrum indicated that the band gap of as-synthesized flower-like CuIn0.7Ga0.3S2 microspheres was about 2.427 eV. Raman spectrum of the obtained CuIn0.7Ga0.3S2 exhibited a high-intensity peak at 302 cm−1 could be assigned as A1-mode.