二氧化钛基催化剂催化氧化甲醛的研究进展

Research progress on titanium dioxide based catalysts for catalytic oxidation of formaldehyde

甲醛(HCHO)是一种主要的室内空气污染物,具有高致癌性和致突变性,催化氧化是一种理想而有效的室内消除甲醛的方法。二氧化钛作为载体负载贵金属催化剂在甲醛催化氧化反应中表现出优良的催化性能。本文综述了近年来二氧化钛基催化剂催化氧化甲醛的研究进展,主要总结了二氧化钛的吸附机理,二氧化钛晶体结构、表面形貌及微观结构、表面活性氧物种和还原性等对二氧化钛基负载贵金属催化剂催化氧化甲醛性能的影响,重点关注了催化剂的化学结构性质与甲醛氧化活性的关系,并归纳了一部分甲醛催化氧化反应机理。最后指出二氧化钛基催化剂在甲醛催化氧化反应中未来研究方向为:合理设计TiO2各种缺陷和晶面暴露,同时提高贵金属的分散性和原子利用效率,继而进一步提高催化剂的性能;在保持催化剂高活性、高稳定性的同时,推进设计实际应用整体式催化剂的研究进程。

Formaldehyde(HCHO) is a primary indoor air pollutant with high carcinogenicity and mutagenicity. Catalytic oxidation is an ideal and effective method for indoor HCHO removal. Titanium dioxide as a carrier to support noble metal catalyst has showed excellent catalytic performance in the catalytic oxidation of formaldehyde. This review introduces recent progress of titanium dioxide based catalysts for catalytic oxidation of HCHO, summarizes the adsorption mechanisms of titanium dioxide, and analyzes the effects of titanium dioxide crystal structure, surface morphology and microstructure, surface active oxygen species and reducibility on the catalytic oxidation performance of HCHO with the focus on the relationship between the chemical and structural properties of catalysts and HCHO oxidation activity.Finally, the future research directions of titanium dioxide based catalysts in HCHO catalytic oxidation are given, namely, to further enhance the catalytic activity by reasonably designing various defects and crystal surface exposure of TiO2, to improve the dispersion of precious metals and atomic utilization efficiency,and to speed up the designing and practical application of monolithic catalyst while maintaining the high activity and stability of the catalyst.