Influence of Surfactant PVP and CTAB Synergistic Effect on the Preparation of Cu_2ZnSnS_4 (CZTS) Particles

Quaternary kesterite Cu2ZnSnS4(CZTS) particles were successfully synthesized by a facile solvothermal method in ethylene glycol with the presence of different ratio of surfactant,using CuCl2·2H2O、Zn(Ac)2·2H2O and SnCl4·5H2O as metal precursor and thiourea as sulfur source. Different morphologies CZTS particles were obtained by different contents of PVP and CTAB. The structure,morphology and absorption spectra of the as-obtained CZTS particles were characterized by means of Xray diffraction(XRD),scanning electron microscopy(SEM) and UV-Vis spectroscopy. The results revealed that the structure of as-synthesized CZTS particles is kesterite; the morphology and optical band-gap of CZTS has occurred a certain change with different ratios of PVP and CTAB. When PVP and CTAB ratio of 3∶1 was added to the reaction system,uniform and mono- disperse flower- like CZTS particles were obtained,the band gap of the CZTS is about 1.48 eV,which approaches the optimum value for solar photoelectric conversion. Finally,a possible fabrication mechanisms of CZTS particles was also inferred.