近日，天津大学叶龙团队报道了侧链氘化使有机光电二极管溶液聚集体的高对比度中子散射和提高器件性能。这一研究成果发表在2026年1月22日出版的《中国化学》杂志上。

理解共轭聚合物的溶液态聚集行为，对于调控其薄膜微观结构与提升光电器件性能至关重要。然而，由于给体:受体共混体系成分复杂且对比度有限，解析其中的聚集体结构仍具挑战。

研究组通过选择性氘代聚(3-己基噻吩)（P3HT）的侧链制备出P3HT-D，显著提升了其中子散射长度密度。该同位素修饰使得聚合物:非富勒烯受体共混溶液中聚合物聚集行为的高对比度小角中子散射分析成为可能。增强的对比度克服了传统X射线散射与显微技术的局限性，能够明确解析链构象与聚集体结构。采用P3HT-D制备的光电二极管展现出更高的响应度，并实现了5.67×10¹³ Jones的比探测率。

这些改善归因于同位素取代所促成的精细薄膜形貌、更优相容性以及降低的非辐射复合。该研究表明，侧链氘代具有双重优势：既实现了精确的结构表征，又能通过调节分子间相互作用提升器件性能。这项工作确立了侧链氘代作为一种通用策略，可用于共轭聚合物基有机光电二极管的结构分析、微结构工程与性能优化。

附：英文原文

Title: Side-Chain Deuteration Enables High-Contrast Neutron Scattering of Solution Aggregates in Organic Photodiodes and Enhances Device Performance

Author: Junjiang Wu, Mengyuan Gao, Kai Zhang, Sunsun Li, Hua Yang, Hanqiu Jiang, Yubin Ke, Huiliang Sun, Long Ye

Issue&Volume: 2026-01-22

Abstract: Understanding the solution-state aggregation of conjugated polymers is essential for controlling their film microstructure and improving optoelectronic device performance. However, resolving aggregate structures in donor:acceptor blends remains challenging due to limited contrast and the multicomponent nature of these systems. Here, we selectively deuterate the side chains of poly(3-hexylthiophene) (P3HT) to produce P3HT-D, substantially increasing its neutron scattering length density (SLD). This isotopic modification enables high-contrast small-angle neutron scattering (SANS) analysis of polymer aggregation in solutions of polymer:nonfullerene acceptor (NFA) blends. The enhanced contrast overcomes the deficiencies of conventional X-ray scattering and microscopy, allowing for unambiguous determination of chain conformation and aggregate structure. Photodiodes incorporating P3HT-D show improved responsivity and achieve a high specific detectivity of 5.67 ×1013 Jones. These improvements are attributed to refined film morphology, improved miscibility, and reduced nonradiative recombination facilitated by isotopic substitution. Our findings demonstrate that side-chain deuteration provides a dual benefit: (i) enabling precise structural characterization and (ii) tuning intermolecular interactions to improve device performance. This study establishes side-chain deuteration as a versatile strategy for structural analysis, microstructure engineering, and performance optimization in conjugated polymer–based organic photodiodes.

DOI: 10.1002/cjoc.70474

Source: https://onlinelibrary.wiley.com/doi/10.1002/cjoc.70474