Chlorine management of a carbon counter electrode for high performance printable perovskite solar cells

Abstract

The printable HTM-free (HTM = hole transport materials) mesoporous carbon-based perovskite solar cells (C-PSCs) are one of the most promising technologies because of their simple production process, lost-cost and excellent stability. In this study, a novel and secure method is used to modify the original graphite, and the obtained chlorinated graphites (C–Cl_x, x = 0.2, 0.4, and 0.6) are applied to counter electrodes (CEs) in the printing of C-PSCs based on the TiO₂/ZrO₂/(5-AVA)_x(MA)_1−xPbI₃/C–Cl_x structure. The experimental results show that C–Cl_x (x = 0.2, 0.4, and 0.6) can effectively improve the efficiency of C-PSCs. The mesoporous PSCs based on C–Cl_0.4 CE have achieved an average efficiency of 11.81%, which is about 1.46-times of the pristine device with carbon CE, and the short-circuit current density (J_sc), fill factor (FF) and open-circuit voltage (V_oc) increased by 15.8%, 11.7% and 11.2%, respectively. Simultaneously, a 30 day aging test showed that PSCs based on (5-AVA)_x(MA)_1−xPbI₃ and C–Cl_x CEs showed excellent stability under ambient air conditions.