Desirable Uniformity and Reproducibility of Electron Transport in Single‐Component Organic Solar Cells

Abstract Despite the simplified fabrication process and desirable microstructural stability, the limited charge transport properties of block copolymers and double‐cable conjugated polymers hinder the overall performance of single‐component photovoltaic devices. Based on the key distinction in the donor (D)–acceptor (A) bonding patterns between single‐component and bulk heterojunction (BHJ) devices, rationalizing the difference between the transport mechanisms is crucial to understanding the structure–property correlation. Herein, the barrier formed between the D–A covalent bond that hinders electron transport in a series of single‐component photovoltaic devices is investigated. The electron transport in block copolymer‐based devices is strongly dependent on the electric field. However, these devices demonstrate exceptional advantages with respect to the charge transport properties, involving high stability to compositional variations, improved film uniformity, and device reproducibility. This work not only illustrates the specific charge transport behavior in block copolymer‐based devices but also clarifies the enormous commercial viability of large‐area single‐component organic solar cells (SCOSCs).