Zhang Yi, Wei Qingyun, He Zhilong, Wang Yan, Shan Tong, Fu Yanyan, Guo Xiaojun, Zhong Hongliang
School of Chemistry and Chemical Engineering, Shanghai Key Lab of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai 200240, China.
State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, China.
ACS Appl Mater Interfaces. 2022 Jul 13;14(27):31066-31074. doi: 10.1021/acsami.2c06277. Epub 2022 Jun 28.
Organic optoelectronic devices exhibit distinctive photoresponse to the near-infrared (NIR) light and show great potential in many fields. However, the optoelectronic properties of the existing devices hardly meet the technical requirements of new applications such as energy conversion and health sensing, thus raising the demand to develop high-performance NIR organic semiconductors. To address this issue, a new NIR material, namely, BFIC, is designed and synthesized by inserting fluorothieno[3,4-]thiophene (FTT) as a π-bridge. Since the introduction of FTT can extend the conjugation, stabilize the quinoid resonant structure, and enhance the intramolecular charge transfer, BFIC displays a broad and intense absorption in the NIR region, ranging from 700 to 1050 nm. As a result, the organic solar cell based on BFIC and a polymer donor PTB7-Th realizes a power conversion efficiency of 10.38%. The semitransparent organic solar cell (OSC) shows a power conversion efficiency of 6.15%, accompanied by an average visible transmittance of 38.79% due to the selective photoresponse in the NIR range. The organic photodetector based on PTB7-Th:BFIC delivers a broad spectral response ranging from 330 to 1030 nm with a specific detectivity over 10 Jones under the self-powered mode, which is one of the highest detectivities among the broad-band organic photodetectors.
有机光电器件对近红外（NIR）光表现出独特的光响应，在许多领域具有巨大潜力。然而，现有器件的光电性能很难满足能量转换和健康传感等新应用的技术要求，因此对开发高性能近红外有机半导体的需求日益增加。为了解决这个问题，通过插入氟噻吩并[3,4-b]噻吩（FTT）作为π桥，设计并合成了一种新型近红外材料BFIC。由于FTT的引入可以扩展共轭、稳定醌型共振结构并增强分子内电荷转移，BFIC在700至1050nm的近红外区域表现出宽泛且强烈的吸收。结果，基于BFIC和聚合物给体PTB7-Th的有机太阳能电池实现了10.38%的功率转换效率。半透明有机太阳能电池（OSC）的功率转换效率为6.15%，由于在近红外范围内的选择性光响应，平均可见光透过率为38.79%。基于PTB7-Th:BFIC的有机光电探测器在自供电模式下具有330至1030nm的宽光谱响应，比探测率超过10 Jones，这是宽带有机光电探测器中最高的比探测率之一。
