PY‐IT, an Excellent Polymer Acceptor†.

Comprehensive Summary: All‐polymer solar cells (all‐PSCs) have attracted considerable attention due to their inherent advantages over other types of organic solar cells, including superior optical and thermal stability, as well as exceptional mechanical durability. Recently, all‐PSCs have experienced remarkable advancements in device performance thanks to the invention of polymerized small‐molecule acceptors (PSMAs) since 2017. Among these PSMAs, PY‐IT has garnered immense interest from the scientific community due to its exceptional performance in all‐PSCs. In this review, we presented the design principles of PY‐IT and discussed the various strategies employed in device engineering for PY‐IT‐based all‐PSCs. These strategies include additive and interface engineering, layer‐by‐layer processing methods, meniscus‐assisted coating methods, and ternary strategy. Furthermore, this review highlighted several novel polymeric donor materials that are paired with PY‐IT to achieve efficient all‐PSCs. Lastly, we summarized the inspiring strategies for further advancing all‐PSCs based on PY‐IT. These strategies aim to enhance the overall performance and stability of all‐PSCs by exploring new materials, optimizing device architectures, and improving fabrication techniques. By leveraging these approaches, we anticipate significant progress in the development of all‐PSCs and their potential as a viable renewable energy source. [ABSTRACT FROM AUTHOR]