Semi-transparent rounded Cu2ZnSnS4 (CZTS) nanosheet networks were in situ grown on a FTO glass substrate, via an effective solution method, without any post-treatments. An improved power conversion efficiency of 6.24% was obtained by applying CZTS nanosheet networks as a counter electrode for dye-sensitized solar cells. When assisted by a mirror reflection, the PCE increased to 7.12%.

Cu 2 ZnSnS 4 (CZTS) as a narrow band gap semiconductor had been used to couple with TiO 2 for enhancing the utilization of solar energy. In this article, the TiO 2-thiol reduce grapheme oxide (TrGO)-CZTS heterostructure is constructed via a facile in-situ solvothermal method. The in-situ solvothermal method could acquire the uniform particles sizes and no aggregation of CZTS by adjusting the sulfur source and reactant solvent. The formation mechanism of TiO 2-TrGO-CZTS structure and the combination behavior of TrGO and CZTS were proposed. The thiol groups in TrGO give the site for CZTS to grow and form the chemical bond which could stabilize the connection of CZTS and TrGO. The in-situ reaction CZTS composite electrode exhibited a better photoelectrochemical performance than the self-assemble CZTS.