Investigation of ZnS films prepared with different solvents and zinc sources under different experimental conditions

ZnS films were prepared by chemical co-reduction method in this work. The influencing factors such as the kind of the solvent, reaction temperature and holding time on ZnS films were mainly investigated by repeated experiments. Experimental results show that, when using different solvents and zinc sources, the X-ray diffraction (XRD) peak intensities of ZnS products obtained by using ethanol as the solvent are much higher than those obtained by using ethylene glycol as the solvent. The ZnS film prepared from zinc source is uniform and compact with round particles arranged regularly. When using ethanol as the solvent, the target product ZnS phase is more easily obtained with ZnO as the zinc source. When holding at 140–180 °C for 20 h, with the increase of temperature the XRD intensity of ZnS phase increases, and the crystallinity becomes better with mostly ZnS spherical particles about 1 μm in diameter microscopically. Impurities ZnO appeared at higher temperature. The ZnS film with pure phase was obtained at 180 °C for 20 h with high XRD intensity and good crystallinity; The XRD peaks at 2θ angles of 28.654°, 48.674° and 56.561° correspond to the (1 0 2)/(0 0 6), (1 1 0)/(1 0 8) and (1 1 6) crystal planes; The extension of the reaction time favors the formation of the target product phase. The ZnS film prepared at 180 °C for 20 h has flat surface, uniform size and dense arrangement with the average resistivity of 0.048 kΩ·cm. Keywords: Photoelectric materials, Sphalerite, Wurtzite, ZnO, ZnS, Chemical co-reductio