Effect of substrate temperature on the properties of spray-deposited Cu2NiSnS4 films

Recently, quaternary Cu2NiSnS4 (CNTS) material has emerged as one of the best promising materials for photovoltaic applications. The spray pyrolysis method was employed to deposit CNTS films by varying substrate temperatures from 250 to 450 degrees C. All the XRD patterns are polycrystalline with (111) preferred orientation having the crystallite size of 11 nm. The compact, interconnected grains with sizes ranging from 130 to 250 nm are observed from the SEM analysis. The Raman peaks observed at 291, 335, and 348 cm-1 correspond to the cubic CNTS phase. Also, the NiS1.97 and Cu8S5 secondary phases are occurred at 137 and 477 cm-1, respectively. All films show the presence of Cu:Ni:Sn:S with good elemental composition. Taut plot shows the band gap of 1.49 eV for cubic CNTS along with NiS1.97 (1.37 eV) and Cu8S5 (1.38 eV) phases. So, the CNTS material can be a good candidate for photovoltaic applications.