Abstract：
Covalent organic frameworks have recently shown high potential for photocatalytic hydrogen production. However, their structure-property-activity relationship has not been sufficiently explored to identify a research direction for structural design. Herein, we report the design and synthesis of four benzotrithiophene (BTT)-based covalent organic frameworks (COFs) with different conjugations of building units, and their photocatalytic activity for hydrogen production. All four BTT-COFs had slipped parallel stacking patterns with high crystallinity and specific surface areas. The change in the degree of conjugation was found to rationally tune the rate of photocatalytic hydrogen evolution. Based on the experimental and calculation results, the tunable photocatalytic performance could be mainly attributed to the electron affinity and charge trapping of the electron accepting units. This study provides important insights for designing covalent organic frameworks for efficient photocatalysts.
摘要：
共价有机骨架最近显示出光催化制氢的高潜力。然而,它们的结构-性质-活动关系尚未得到充分探索，无法确定结构设计的研究方向。在这里，我们报告了四个苯并三噻吩（BTT）为基础的共价有机骨架（COF）的设计和合成，具有不同的结构单元共轭，以及它们对制氢的光催化活性。所有四个BTT-COF都具有具有高结晶度和比表面积的滑动平行堆叠图案。发现共轭程度的变化可以合理地调节光催化析氢的速率。根据实验和计算结果，可调谐的光催化性能主要归因于电子接受单元的电子亲和力和电荷捕获。这项研究为设计高效光催化剂的共价有机框架提供了重要的见解。
