Concentration effect on the chain structure and photoelectric properties of conjugated polymer precursor solutions and thin films: A mini review

Abstract Conjugated polymers have attracted extensive attention in numerous research fields because of their exceptional photoelectric properties and distinctive solution processing capabilities. The conformation of the chain and the structure of the condensed state in solution are closely related to various factors, such as concentration and solvent. Concentration, as a significant external parameter, plays a crucial role in the self‐assembly and formation of crystalline structures in conjugated polymers. It also affects the properties of the solution, the structure of the membrane, and the performance of the fabricated devices. Recently, there have been an increasing number of studies conducted from the perspective of solution concentration. Therefore, it is important to comprehensively summarize the effect of concentration on the transition process of chain structure from solution to film, as well as the impact of concentration on the performance of related devices. In this review, we summarize the effects of concentration on the chain motion, particle size, ordered structure, and photoelectric properties of conjugated polymers in solutions and thin films, as well as on device efficiency. This provides a unique perspective on the fundamental characteristics of conjugated polymers, which can assist in the development and improvement of optoelectronic devices.