Non‐Conjugated Polymer as an Efficient Dopant‐Free Hole‐Transporting Material for Perovskite Solar Cells

Abstract A new non‐conjugated polymer (PVCz‐OMeDAD) with good solution processability was developed to serve as an efficient dopant‐free hole‐transporting material (HTM) for perovskite solar cells (PSCs). PVCz‐OMeDAD was simply prepared by the free‐radical polymerization of vinyl monomers, which were synthesized from low‐cost raw materials through three high‐yield synthesis steps. The combination of the flexible non‐conjugated polyvinyl main chain and hole‐transporting methoxydiphenylamine‐substituted carbazole side chains endowed PVCz‐OMeDAD with excellent film‐forming ability, a suitable energy level, and high hole mobility. As a result, by using an ultra‐thin (≈30 nm) PVCz‐OMeDAD film as cost‐effective dopant‐free polymer HTM, the conventional n–i–p‐type PSCs demonstrated a power conversion efficiency (PCE) up to 16.09 %, suggesting the great potential of the polymer film for future low‐cost, large‐scale, flexible PSCs applications.