Abstract:The influence of different sulfur sources on the size and morphology of Cu2ZnSnS4(CZTS) nanoparticles is studied by the microwave irradiation assisted solvothermal method. The results show that:500 nm sphere-like CZTS nanoparticles are synthesized with thiourea as a sulfur source. The 50 nm hollow sphere-like CZTS nanoparticles are obtained using L-cysteine as a sulfur source. And the average size of CZTS nanoparticles with thioacetamide as a sulfur source is only 3 nm. The nano-ink is firstly prepared by large size nanoparticles (average size of 500 nm or 50 nm). When this nano-ink is used to prepare thin film by spin-coating, the as-obtained thin film has poor density and many holes. However, when the nano-ink prepared by small size nanoparticles (average size of 3 nm) is used to prepare thin film, the thin film with best density and uniformity is obtained. Moreover,when the best as-prepared thin film is sulfurized,its crystallinity is obviously improved, and the CZTS solar cell with 2.1% efficiency is obtained.