Rapid microwave-assisted solvothermal synthesis of Cu_2ZnSnS_4 (CZTS) nanocrystals for low-cost thin film photovoltaic: investigation of synthesis parameters and morphology control

摘要

AbstractNanocrystals of CZTS have been synthesized by solvothermal technique using rapid microwave aided heating. The effects of synthesis parameters, such as reaction temperature, reaction time, precursor concentration, various surfactants, were investigated. Samples were characterised by XRD, Raman spectroscopy, XPS, FEGSEM-EDS, FEGTEM for phase, crystallinity, morphology and compositional information. The optical properties of the samples were investigated with UV–Vis spectroscopy. Uniform hierarchical flowerlike morphology was obtained at 180 °C for 30 min reaction time. The band gap was found to be 1.57 eV which is suitable for photovoltaic applications. The flower like morphology was changed to spherical type when the concentration of the reactants increased from 2 to 10 mM. Use of PVP along with the reactants had a pronounced effect on particle morphology and size. The growth mechanism of the CZTS particles synthesized without any surfactant and with addition of PVP surfactant was discussed.