Built-in Electric Field in Quasi-2D CsPbI3 Perovskites Using High-Polarized Zwitterionic Spacer for Enhanced Charge Separation/Transport

Two-dimensional (2D) halide perovskites are promisingcandidatesfor the fabrication of stable and high-efficiency solar cells. However,the low power conversion efficiency (PCE) of cell devices using 2Dperovskites is attributed to reduced charge transport caused by poororganic barrier conductivity. In this study, we propose the use ofa high-polarized organic zwitterionic spacer, p-aminobenzoicacid (PABA), to construct novel quasi-2D perovskite structures withenhanced self-driven charge separation and transfer. The NH3 (+) and COO- groups in PABA generate analigned electric field, promoting carrier separation and aggregationon the opposite edges of the inorganic layer. This enables efficientin-plane transportation along the inorganic layer. Additionally, PABAintercalated quasi-2D perovskite exhibits improved stability comparedwith counterparts with diamine cation spacers due to the strong interactionbetween -COO- and inorganic layers. Our findingssuggest that high-polarized organic zwitterionic spacers, with NH3 (+) and COO- functionality, holdpromise for stable and efficient quasi-2D perovskite solar cells.

Automated summary

This study proposes the use of a high-polarized organic zwitterionic spacer, p-aminobenzoic acid (PABA), to construct novel quasi-2D perovskite structures for stable and efficient solar cells.