Cove‐Edge Nanoribbon Materials for Efficient Inverted Halide Perovskite Solar Cells

Abstract Two cove‐edge graphene nanoribbons hPDI2‐Pyr‐hPDI2 ( 1 ) and hPDI3‐Pyr‐hPDI3 ( 2 ) are used as efficient electron‐transporting materials (ETMs) in inverted planar perovskite solar cells (PSCs). Devices based on the new graphene nanoribbons exhibit maximum power‐conversion efficiencies (PCEs) of 15.6 % and 16.5 % for 1 and 2 , respectively, while a maximum PCE of 14.9 % is achieved with devices based on [6,6]‐phenyl‐C 61 ‐butyric acid methyl ester (PC 61 BM). The interfacial effects induced by these new materials are studied using photoluminescence (PL), and we find that 1 and 2 act as efficient electron‐extraction materials. Additionally, compared with PC 61 BM, these new materials are more hydrophobic and have slightly higher LUMO energy levels, thus providing better device performance and higher device stability.