通过简单的溶剂热法合成了锌黄锡矿结构的Cu2ZnSnS4 (CZTS)纳米晶,使用L-半胱氨酸作硫源和络合剂,以金属氯化物作前驱体,在180 °C下反应16 h成功获得了CZTS微球.使用X 射线衍射(XRD)仪,场发射扫描电子显微镜(FESEM)、能量色散谱(EDS)、高分辨透射电子显微镜(HRTEM)、多功能X射线光电子能谱仪(XPS)、紫外-可见(UV-Vis)分光光度计对产物的物相、结构、形貌及光学性能进行表征.结果表明:所得的产物为纯相锌黄锡矿结构的CZTS纳米颗粒,CZTS微球直径为400-800 nm,并可观察到微球是由大量厚度约20nm的纳米片构成; 将CZTS颗粒均匀分散在异丙醇中,测试后估算其禁带宽度约1.58 eV,与薄膜太阳能电池所需的最佳禁带宽度相近.并对其形成机理进行了初步探讨.
A simple solvothermal route has been successfully used to prepare Cu2ZnSnS, nanocrystals using metal chloride and L-cysteine as precursors at 180℃ for 16 h. L-cysteine was used as the sulfide source and complexing agent. The phase, structure, morphology, and optical properties of the assynthesized products were characterized by powder X-ray diffraction (XRD), field-emission scan electron microscopy (FESEM), energy dispersive spectrometry (EDS), high-resolution electron transmission microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet-visible (UV-Vis) spectrophotometer. The results showed that pure kesterite-type Cu2ZnSnS, nanocrystals were prepared under this condition and the diameters of the microspheres were about 400-800 nm while the microspheres consisted of nanoflakes with thickness of 20 nm. The band gap of CZTS nanoparticles was about 1.58 eV, which was close to the optimum band gap of thin film solar cells. A possible formation mechanism was also discussed.