Li Shengxu, Ma Rui, Xu Shunqi, Zheng Tianyue, Fu Guangen, Wu Yanling, Liao Zhongquan, Kuang Yongbo, Hou Yang, Wang Dashuai, Petkov Petko Stoev, Simeonova Kristina, Feng Xinliang, Wu Li-Zhu, Li Xu-Bing, Zhang Tao
Key Laboratory of Marine Materials and Related Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, The Chinese Academy of Sciences, Beijing 100190, China.
J Am Chem Soc. 2022 Aug 3;144(30):13953-13960. doi: 10.1021/jacs.2c06042. Epub 2022 Jul 25.
Vinylene/olefin-linked two-dimensional covalent organic frameworks (v-2D-COFs) have emerged as advanced semiconducting materials with excellent in-plane conjugation, high chemical stabilities, and precisely tunable electronic structures. Exploring new linkage chemistry for the reticular construction of v-2D-COFs remains in infancy and challenging. Herein, we present a solid-state benzobisoxazole-mediated aldol polycondensation reaction for the construction of two novel isomeric benzobisoxazole-bridged v-2D-COFs (v-2D-COF-NO1 and v-2D-COF-NO2) with and configurations of benzobisoxazole. Interestingly, the isomeric benzobisoxazole linkers endow the two v-2D-COFs with distinct optoelectronic and electrochemical properties, ranging from light absorption and emission to charge-transfer properties. When employed as the photocathode, v-2D-COF-NO1 exhibits a photocurrent of up to ∼18 μA/cm under AM 1.5G irradiation at -0.3 V vs reversible hydrogen electrode (RHE), which is twice the value of v-2D-COF-NO2 (∼9.1 μA/cm). With Pt as a cocatalyst, v-2D-COF-NO1 demonstrates a photocatalytic hydrogen evolution rate of ∼1.97 mmol h g, also in clear contrast to that of v-2D-COF-NO2 (∼0.86 mmol h g) under identical conditions. This work demonstrates the synthesis of v-2D-COFs via benzobisoxazole-mediated aldol polycondensation with isomeric structures and distinct photocatalytic properties.
亚乙烯基/烯烃连接的二维共价有机框架（v-2D-COFs）已成为具有优异面内共轭、高化学稳定性和精确可调电子结构的先进半导体材料。探索用于v-2D-COFs网状结构构建的新连接化学仍处于起步阶段且具有挑战性。在此，我们提出一种固态苯并双恶唑介导的羟醛缩聚反应，用于构建两种具有苯并双恶唑 和 构型的新型异构苯并双恶唑桥联v-2D-COFs（v-2D-COF-NO1和v-2D-COF-NO2）。有趣的是，异构苯并双恶唑连接体赋予这两种v-2D-COFs不同的光电和电化学性质，从光吸收和发射到电荷转移性质。当用作光阴极时，在相对于可逆氢电极（RHE）为-0.3 V的AM 1.5G光照下，v-2D-COF-NO1表现出高达约18 μA/cm²的光电流，是v-2D-COF-NO2（约9.1 μA/cm²）的两倍。以铂作为助催化剂，在相同条件下，v-2D-COF-NO1的光催化析氢速率约为1.97 mmol h⁻¹ g⁻¹，这也与v-2D-COF-NO2（约0.86 mmol h⁻¹ g⁻¹）形成鲜明对比。这项工作展示了通过苯并双恶唑介导的羟醛缩聚反应合成具有异构结构和不同光催化性质的v-2D-COFs。
