Influence of nitrogen atmosphere one-step heating assisted the solution processing of Kesterite Cu2ZnSnS4 as hole extraction on the efficacy of the inverted perovskite solar cells

Aside from perovskite crystallization effectuation, the hole transport layer (HTL) acting a significant role in regulating charge transportation for inverted perovskite solar cells (PSCs). Herein, we show effective p-i-n PSCs based on solid solution-coating Kesterite Cu 2 ZnSnS 4 (CZTS) by one-step heating as HTL in an air (O 2 ) and nitrogen (N 2 ) environment. The spin-coating method is optimized to produce CZTS-HTL with the necessary phase purity and optimum film coverage. In comparison to the O 2 environment, photoluminescence (PL) tests show that the CZTS-HTL based on N 2 delivers better hole extraction. The N 2 annealing environment achieves a substantial power conversion efficiency (PCE) of 13.95% for CZTS-HTL based inverted PSC, compared to 9.43% for air-annealed devices.