共价有机骨架(COFs)在光催化还原CO2方面具有巨大的潜力,由于其可调节的结构,多孔特性,和高度有序的自然。然而,光吸收差,光生电子-空穴对的快速复合,和次优的配位条件导致了光催化CO2还原过程中观察到的受阻效率和选择性。在这项工作中,通过溶剂热方法,通过涉及镍(II)四氨基酞菁(NiTAPc)和3,6-二溴苯四甲酸二酐(BPMDA)的合成过程,将溴(Br)原子整合到COF中。与不含溴的COF相比,多孔骨架结构的偶联以及Br原子的掺入显着提高了光电性能。同时,X射线光电子能谱(XPS)和密度泛函理论(DFT)计算表明,Br原子的引入可以促进酞菁单元周围电子构型的调整,并减少光催化反应所需的能量。当受到可见光照射时,NiTAPc-BPMDACOF在5小时内显示出148.25μmolg-1的CO产量,伴随着令人印象深刻的98%的选择性。这项工作突出了基于COF的光催化剂中酞菁和Br原子的协同影响,为设计和构建具有高产率和选择性的高性能光催化剂提供了一种替代方法。基于COF的光催化剂中酞菁和Br原子的协同作用为将来具有高产率和选择性的光催化剂提供了替代策略。
Covalent organic frameworks (COFs) have great potential for photocatalytic CO2 reduction, owing to their adjustable structures, porous characteristics, and highly ordered nature. However, poor light absorption, fast recombination of photogenerated electron-hole pairs, and suboptimal coordination conditions have contributed to the hindered efficiency and selectivity observed in photocatalytic CO2 reduction processes. In this work, the integration of bromine (Br) atoms into COFs was achieved through the synthesis process involving nickel (II) tetraaminophthalocyanine (NiTAPc) and 3,6-dibromopyromellitic dianhydride (BPMDA) using a solvothermal approach. The coupling of a porous framework structure alongside the incorporation of Br atoms yields a significant enhancement in photoelectric properties compared to bromine-free COFs. Meanwhile, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that the introduction of Br atoms can facilitate the adjustment of the electron configuration around the phthalocyanine unit and diminish the required energy for the photocatalytic reaction. When subjected to visible light irradiation, the NiTAPc-BPMDA COF showcased a CO yield of 148.25 μmol g-1 over a 5-hour period, accompanied by an impressive selectivity of 98%. This work highlights the collaborative influence of phthalocyanines and Br atoms within COF-based photocatalysts, offering an alternative approach for designing and constructing high-performance photocatalysts with elevated yield and selectivity. The synergistic role of phthalocyanines and Br atoms within the COF-based photocatalysts provides an alternative strategy for photocatalysts with high yield and selectivity in the future.