Scalable one-step heating up synthesis of Cu2ZnSnS4 nanocrystals hole conducting materials for carbon electrode based perovskite solar cells

Abstract Cu2ZnSnS4 nanocrystal is a highly potential inorganic hole conducting material for perovskite solar cells employing low temperature carbon electrodes, which exhibit great prospect in future commercialization. However, Cu2ZnSnS4 nanocrystals are most commonly synthesized using the hot-injection method, which is not suitable for mass production. Here, a scalable one-step heating up synthesis method is demonstrated to successfully produce Cu2ZnSnS4 nanocrystals. First, the reaction time is optimized to be 60 min after evaluating the performances of perovskite solar cell employing the small-batch synthesized Cu2ZnSnS4 nanocrystals with different reaction time. Then, gram-scale Cu2ZnSnS4 nanocrystals are successfully synthesized under the optimized reaction time. Using these gram-scale synthesized Cu2ZnSnS4 nanoparticles, the best-performing perovskite solar cell can demonstrate a power conversion efficiency of 16.10%.