A Short Review on Surface‐Confined Monolayers of π‐Conjugated Polymers for Photovoltaics

π‐conjugated polymer (CPs)‐functionalized semiconductor surfaces are important components of photovoltaic (PV) devices. In this context, the use of surface‐confined monolayers (SCMs) of CPs has attracted great attention due to their operational stability, reliability, and excellent control over the nanostructure and morphology of CP films. The CPs with proper anchoring groups are covalently bonded to the semiconductor surface driven by the interactions between anchors and substrate, forming densely packed and orderly assembled polymer chains in thin films. The nanostructure of CP SCMs is highly dependent on the type and position of anchors, polymer structure, and chain length, as well as the film‐forming techniques. Herein, general features, anchoring mechanism, grafting approaches, and PV properties of CP SCMs are described and analyzed. Then, the applications of CP monolayers as photosensitizers for dye sensitized solar cells and hole transport interlayers for bulk‐heterojunction polymer solar cells and perovskite solar cells are summarized. With the structure tunability, future study directions for CP SCMs in terms of structure effect, assembly states, and efficiency enhancement are discussed.