Zhao Xin, Liu Qianxi, Li Qi, Yin Yihang, Zheng Mang, Luo Fanqi, Gu Huiquan, Jiang Baojiang
Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People's Republic of China, School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, PR China.
College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150080, PR China.
J Colloid Interface Sci. 2025 May;685:1068-1076. doi: 10.1016/j.jcis.2025.01.231. Epub 2025 Jan 27.
Photocatalytic reduction of CO to valuable chemicals is an effective strategy to address the environmental problems and energy crisis. Covalent organic frameworks (COFs) are emerging materials known for their excellent diverse properties, albeit limited by special synthetic methods, including high temperature (120 °C) and the necessity of inert gas atmosphere. Herein, a novel synthesis method under room temperature and air was optimized to form TpPa-COF (TP-COF) by p-phenylenediamine (Pa) and 2,4,6-triformyl phloroglucinol (Tp) through electrostatic self-assembly. To further expand the application scope of TP-COF, a heterojunction structure was constructed by in-situ growth of TP-COF onto TiO to form TiO@TP-COF. In the photocatalytic CO reaction of TiO@TP-COF composites, TiO acts as a reduction site to reduce CO to CO, and triethanolamine (TEOA) acts as a hole-sacrificing reagent. It was demonstrated by in situ X-ray photoelectron spectroscopy (XPS) that the direction of electron transfer in the TiO@TP-COF composites flowed from TP-COF to TiO. Meanwhile, TEOA on TP-COF was oxidized to consume holes and produce protons for the reduction of CO. Combining the advantages of organic and inorganic semiconductors, the heterojunction structure effectively improves the photocatalytic properties of TiO@TP-COF under visible light irradiation. TiO@TP-COF demonstrates a remarkable photocatalytic CO reduction rate of 133.37 μmol/g/h at λ = 420 nm, which is 3.19 and 2.88 times higher than that of TP-COF and TiO, respectively, while exhibiting a selectivity of 73 % for CO. This convenient method of synthesizing TiO@TP-COF catalysts will open up new perspectives for future COF-based materials.
光催化将CO还原为有价值的化学品是解决环境问题和能源危机的有效策略。共价有机框架（COFs）是一种新兴材料，以其优异的多样性能而闻名，尽管受到特殊合成方法的限制，包括高温（120°C）以及惰性气体气氛的必要性。在此，优化了一种在室温及空气中的新型合成方法，通过对苯二胺（Pa）和2,4,6-三羟基间苯三甲醛（Tp）经静电自组装形成TpPa-COF（TP-COF）。为进一步扩大TP-COF的应用范围，通过在TiO上原位生长TP-COF构建异质结结构以形成TiO@TP-COF。在TiO@TP-COF复合材料的光催化CO反应中，TiO作为还原位点将CO还原为CO，三乙醇胺（TEOA）作为空穴牺牲试剂。原位X射线光电子能谱（XPS）表明，TiO@TP-COF复合材料中的电子转移方向是从TP-COF流向TiO。同时，TP-COF上的TEOA被氧化以消耗空穴并产生质子用于CO的还原。结合有机和无机半导体的优点，异质结结构有效地提高了TiO@TP-COF在可见光照射下的光催化性能。TiO@TP-COF在λ = 420 nm时表现出显著的光催化CO还原速率，为133.37 μmol/g/h，分别比TP-COF和TiO高3.19倍和2.88倍，同时对CO的选择性为73%。这种合成TiO@TP-COF催化剂的简便方法将为未来基于COF的材料开辟新的前景。
