Wang Yu, Wu Huang, Zhu Weigang, Zhang Xiaotao, Liu Zheyuan, Wu Yishi, Feng Changfu, Dang Yanfeng, Dong Huanli, Fu Hongbing, Hu Wenping
Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University & Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin, 300072, China.
Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA.
Angew Chem Int Ed Engl. 2021 Mar 15;60(12):6344-6350. doi: 10.1002/anie.202015326. Epub 2021 Feb 10.
Large-area 2D cocrystals with strong near-infrared (NIR) absorption have been designed and prepared. Driven by the intermolecular charge-transfer (CT) interactions, zinc tetraphenylporphyrin (donor) and C (acceptor) self-assemble into a NIR cocrystal with absorption wavelength up to 1080 nm. By tailoring the growth solvents and processes, the cocrystal morphologies can be tuned from 1D nanowires, 2D nanosheets to large-area 2D cocrystal films with length reaching several millimeters. Owing to the highly ordered donor-acceptor arrangement, the CT absorption in the 2D cocrystals is enhanced and is comparable to singlet absorption. The uniform 2D cocrystals, with enhanced CT absorption in the NIR region, displays a high responsivity of 2424 mA W to NIR light and a fast response time of 0.6 s. The excellent device performance is attributed to the generation of long-lived free charge carriers as revealed by transient absorption spectroscopy and optimization of device configuration.
具有强近红外（NIR）吸收的大面积二维共晶体已被设计并制备出来。在分子间电荷转移（CT）相互作用的驱动下，四苯基卟啉锌（供体）和C（受体）自组装成一种吸收波长高达1080 nm的近红外共晶体。通过调整生长溶剂和过程，共晶体形态可以从一维纳米线、二维纳米片调整为长度达几毫米的大面积二维共晶体薄膜。由于供体 - 受体排列高度有序，二维共晶体中的CT吸收增强，与单线态吸收相当。这种均匀二维共晶体在近红外区域具有增强的CT吸收，对近红外光的响应率高达2424 mA W，响应时间为0.6 s。瞬态吸收光谱显示，这种优异的器件性能归因于长寿命自由电荷载流子的产生以及器件结构的优化。
