Solution‐Processed Semiconductor Materials as Cathode Interlayers for Organic Solar Cells

Abstract

AbstractCathode interlayers (CILs) play a crucial role in improving the photovoltaic efficiency and stability of OSCs. CILs generally consists of two kinds of materials, interfacial dipole‐based CILs and SPS‐based CILs. With good charge transporting ability, excellent compatibility with large‐area processing methods, and highly tunable optoelectronic properties, the SPS‐based CILs exhibit remarkable superiorities to their interfacial dipole‐based counterparts in practical use, making them promising candidate in developing efficient CILs for OSCs. This mini‐review highlights the great potential of SPS‐based CILs in OSC applications and elucidates the working mechanism and material design strategy of SPS materials. Afterward, the SPS‐based CIL materials are summarized and discussed in four sections, including organic small molecules, conjugated polymers, nonconjugated polymers, and TMOs. The structure‐property‐performance relationship of SPS‐based CIL materials is revealed, which may provide readers new insight into the molecular design of SPS‐based CILs. The mechanisms to endow SPS‐based CILs with thickness insensitivity, resistance to environmental erosion, and photo‐electric conversion ability are also elucidated. Finally, after a brief summary, the remaining issues and the prospects of SPS‐based CILs are suggested.