Anchorable Polymers Enabling Ultra-Thin and Robust Hole-Transporting Layers for High-Efficiency Inverted Perovskite Solar Cells

Abstract

Coordinative pyridyl units are introduced as side-chains on poly-triarylamine (PTAA) backbone with varied contents by copolymerization method, resulting in chemical interactions between polymeric HTMs and substrates. The strong interaction allows them to be processed into ultra-thin, uniform, and robust hole-transporting layers, greatly decreasing charge transport losses. Based on the optimal CP4, we achieved highly efficient inverted PSCs with power conversion efficiencies (PCEs) up to 26.21 %.