Practical Interface Engineering between Perovskite and Carbon Electrode in Regular Carbon-Based Perovskite Solar Cells
Haixia Xie, Jia Lei, Zijie Zhu, Xinbo Xu, D. M. Li, Jie Xu, Yong Pan, Xingtian Yin
Abstract
Despite the continuous growth in power conversion efficiencies (PCEs) of hole transport layer-free carbon-based perovskite solar cells (HTL-free C-PSCs) due to their enhanced stability and low-cost structure, their performance still lags behind the Shockley–Queisser limit (∼33%) for CH 3 NH 3 PbI 3 PSCs and even regular PSCs with HTL and metal counter electrodes (26.9%). This discrepancy primarily stems from poor physical contact at the perovskite/carbon interface, energy band alignment mismatch, and the inability of the carbon electrode (CE) to reflect incident light. To address these issues, specialized methods and strategies have been developed, yet a comprehensive review focusing on interface engineering between perovskites and CEs in regular C-PSCs remains lacking. This Review highlights recent research progress in interface engineering for C-PSCs, with particular emphasis on modifications at the perovskite/CE interface. It also provides a brief outlook on the challenges and opportunities in advancing the efficiency and stability of C-PSCs through a tailored interfacial engineering. A comprehensive overview diagram is presented that summarizes the unique properties of carbon, the key challenges faced by C-PSCs, and the interfacial engineering strategies employed.