Planar copolymers for high-efficiency polymer solar cells

• 来源期刊: 中国科学:化学（英文版）
• 年，卷（期）: 2019,（1）
• 页码范围: 9-13
• 页数: 5页
• 语种: 英文

摘要

Triggered by the energy crisis and the demand on the clean energy sources in the future,organic solar cells especially conjugated polymer based polymer solar cells (PSCs) arise interests from both industrial and academic sides,due to their unique advantages,including mechanical flexibility,light weight,semi-transparence,solution processability and low fabrication cost.In the early stage,poly(3-hexylthiophene)(P3HT) has been widely studied and proven to be one of the most successful electron donors in PSCs,but the power conversion efficiencies (PCEs) are limited to around ～4％ due to the narrow absorption and incompatible energy level to the fullerene derivatives (PC61BM and PC71BM).In a long period,the exploration of donor materials is one of the popular research topics in the field of PSCs,since fullerene derivatives present universal compatibility to different type polymer donors.For better tailoring the absorption spectra,highest occupied molecular orbital & lowest unoccupied molecular orbital (HOMO & LUMO) energy levels and transport properties,donor-acceptor (D-A) type alternating copolymers have been designed so as to improve the light harvesting ability in virtue of the new hybridized molecular orbitals and narrowed band gaps.Subsequently,researchers were mainly focusing on band gap engineering via developing new donor or acceptor moieties and the absorption coverage could be successfully extended to the NIR region of about 1100 nm by some narrow band gap polymers,but the photovoltaic performances still lag behind.