Phase evolution and sintering behaviors of Cu2ZnSnS4 powders synthesized by mechanochemical process with different milling parameters

The mechanochemical process was employed to synthesize Cu2ZnSnS4 (CZTS) powder using elemental powders of Cu, Zn, Sn and S as the source materials. The phase evolution of the synthesized powders dependent on the milling parameters was systematically researched according to Raman and X-ray diffraction measurements. It is noteworthy that the kesterite CZTS phase were observed in the mechanochemical process milling only for 3 h, but some binary metal sulfides always existed in the synthesized powders. Moreover, the formation mechanism of the CZTS phase in the mechanochemical processes was proposed. Further, the sintering behaviors of the synthesized powders were systematically investigated also, i.e., the effects of sintering temperature and milling parameters were discussed on the phase, residual stress, composition, cross-section morphologies and relative densities. It was found that the longer the milling time and/or the higher the milling rotation speed, the better the sintering properties of the synthesized powders. (C) 2017 Elsevier B.V. All rights reserved.