Rational Backbone Planarization for Doping‐Resilient Polymeric Hole Transport Materials Toward Stable and Scalable Perovskite Solar Cells

ABSTRACT As perovskite solar cells (PSCs) advance toward commercialization, achieving long‐term operational stability and high‐yield large‐area processing has become essential. These requirements are strongly influenced by the doping stability and film uniformity of hole‐transport materials (HTMs). Here, we introduce PDVB14, a PTAA‐based random copolymer incorporating planar divinylbenzene (DVB) units through compositionally reliable Buchwald–Hartwig C–N cross‐coupling. DVB incorporation increases backbone planarity and stabilizes the electronic structure by promoting more delocalized radical‐cation states, while short‐range electronic coupling supports efficient and stable charge transport across a broad doping window. When used as a hole‐transport layer, PDVB14 shows minimal performance dependence on dopant concentration, achieving a champion power conversion efficiency of 23.5% and retaining 20.6% at 1.0 cm ² . It also delivers substantially improved thermal, light, and humidity stability compared PTAA. Dopant‐distribution mapping reveals highly uniform Li profiles across 6 × 6 cm ² films, demonstrating excellent compatibility with large‐area solution processing. This work provides a molecular design strategy that overcomes key structural and electronic limitations of PTAA, delivering a doping‐resilient and scalable polymeric HTM platform suited for next‐generation PSC manufacturing.