Novel C₃N₄-Assisted Bilateral Interface Engineering for Efficient and Stable Perovskite Solar Cells

Abstract

g-C3N4-assisted interface engineering has been developed as an effective method to improve the efficiency and stability of perovskite solar cells (PSCs). However, most of the reported works used g-C3N4-induced single-interface modification, which is difficult to passivate the bilateral interfaces of the perovskite layer at the same time. In this paper, we fabricated two kinds of C3N4 materials simultaneously (w-CN and y-CN) after the twice calcination of melamine and used them in the bilateral interface modification toward all-inorganic PSCs. The two kinds of C3N4 play different roles in different interface engineering. On the front interface, w-CN could optimize band level arrangement and improve the perovskite film quality, which contributes to the efficiency of the device. On the back interface, y-CN could also improve the film quality of the perovskite layer, accelerating the extraction of charge carriers. The champion efficiency of the CsPbIBr2-based device treated by the bilateral interface is significantly enhanced from 7.8 to 10.1%. Moreover, the modified perovskite film exhibits negligible degradation after 40 min of exposure in the ambient environment with a relative humidity of 70%, while the pristine perovskite film has a rapid degradation within 20 min.

Recent Progress on Boosting the Perovskite Film Quality of All-Inorganic Perovskite Solar Cells

“…Chen et al [141] enhanced the morphology of CsPbIBr 2 , PCE, and stability by introducing rubidium acetate (RbAc) to the ETL/perovskite/HTL interfaces. Shi et al [142] synthesized two kinds of C 3 N 4 materials (w-CN and y-CN) simultaneously and employed them in the two-sided boundary surface of the perovskite film. Table 3 summarizes the performances of PSCs based on interface engineering.…”

CsPbIBr2‐Based Bifacial Semitransparent Solar Cells for All‐Day Applications

“…The quality of CsPbIBr 2 thin films largely determines the efficiency of PSC devices. Various studies have been widely carried out for improving CsPbIBr 2 crystallinity via interfacial modification and annealing engineering, [45][46][47][48][49][50][51][52][53] but little attention has been paid to the growth process of CsPbIBr 2 crystals before annealing.…”