Research progress on gas pollutants removal by defective metal oxides

doi:10.11949/0438-1157.20241244

Abstract

Abstract:

Metal oxides are widely used in the field of gas purification because of their adjustable structure, easy modification and low cost. However, the reaction activity of metal oxides without defective structures to gaseous pollutants is low, and the selectivity still needs to be improved. After introducing crystal defects into metal oxides, their crystal structure and physicochemical properties can be changed, thereby significantly improving their adsorption activity and selectivity to gases. Nevertheless, in gas removal reactions, the promoting mechanism of defects is extremely complex, which makes it difficult to explore the mechanism of defects in the reaction between metal oxides and gases, and also makes it challenging to apply the research results of reaction mechanism to guide the strategic introduction of defects. In this review, the types of defects in metal oxides are summarized, and then the methods of introducing defects are classified and summarized, and the application status of defect metal oxides in gas purification field in recent years is summarized. Finally, the improvement methods and future research directions of metal oxide defect engineering are prospected, in order to provide reference for the subsequent research on the construction of metal oxide defect engineering and the reaction mechanism of defect promotion.

Key words: metal oxide, defects, gas purification, preparation, adsorption, catalysis

摘要：

金属氧化物因具有结构可调、易于改性、成本低廉等特性，广泛应用于气体净化领域。但未引入缺陷结构的金属氧化物对气体污染物的反应活性较低，且选择性仍有待提高。在金属氧化物中引入晶体缺陷后，能改变其晶体结构和物化性质，进而显著提高其对气体的吸附活性和选择性。但在气体脱除反应中，缺陷的促进作用机制极为复杂，这导致探究金属氧化物与气体反应中的缺陷作用机理变得十分困难，也使得将反应机理的研究成果应用于指导缺陷的策略性引入极具挑战性。首先概述了金属氧化物中的缺陷类型，其次对缺陷引入方法进行了分类概括，并总结了近年来缺陷型金属氧化物在气体净化领域的应用现状。最后，对金属氧化物缺陷工程的改进方法和未来研究方向进行了展望，以期为后续金属氧化物缺陷工程构筑及缺陷促进反应机制研究提供参考。

关键词: 金属氧化物, 缺陷, 气体净化, 制备, 吸附, 催化

CLC Number:

X 511

Shenghua YANG, Yangjie SUN, Xiaojun XUE, Jie MI, Jiancheng WANG, Yu FENG. Research progress on gas pollutants removal by defective metal oxides[J]. CIESC Journal, 2025, 76(6): 2469-2482.

杨盛华, 孙阳杰, 薛晓君, 米杰, 王建成, 冯宇. 缺陷型金属氧化物脱除气体污染物研究进展[J]. 化工学报, 2025, 76(6): 2469-2482.

Figures/Tables 9

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金属氧化物种类	缺陷类型	制备方法	应用	性能	文献
UO₂	氧空位	还原法	含硫气体	—	[48]
Ce_1-_x Zr _x O₂	氧空位	离子掺杂	含硫气体	—	[49]
Cu₂O	氧空位	还原法	含硫气体	—	[37]
Au/CeO₂	氧空位	离子掺杂	含硫气体	—	[50]
NiO/ACF	阳离子空位	热处理	含硫气体	23.65 mg_s/g脱硫剂	[51]
Mn-TiO₂	氧空位	还原法	含硫气体	0.40 ± 0.05（相对浓度）	[52]
ZnO	氧空位	热处理	NO _x	36.7%	[53]
TiO₂	氧空位	热处理	NO _x	—	[54]
Zn₂SnO₄	氧空位	离子掺杂	NO _x	62%	[55]
Ce-SnO₂	氧空位	离子掺杂	NO _x	5.001 μmol/(g·h)	[56]
MnFeO _x /TiO₂	氧空位	还原法	NO _x	> 80%	[57]
Bi₂WO₆	氧空位	离子掺杂	NO _x	64%	[58]
ZnO	氧空位	热处理	NO _x	55.45%	[59]
Cu₂O	氧空位	还原法	CO₂	35.4%（法拉第效率）	[60]
TiO₂-Cu _x O	氧空位、阳离子空位	离子掺杂	CO₂	—	[61]
Bi₄Ti₃O₁₂	氧空位、阳离子空位	还原法	CO₂	4.90 μmol/(g·h)	[62]
ON-CuO	氧空位、面缺陷	离子掺杂	CO₂	56%（法拉第效率）	[44]
Cu/Co₃O₄	氧空位	离子掺杂	CO₂	99%	[63]
TiO₂	氧空位	热处理	CO₂	20.2%	[64]
Cu₂O	线缺陷、面缺陷	还原法	CO₂	48.3%（法拉第效率）	[65]
CeO₂-MgO	氧空位	热处理	VOCs	90%	[66]
MnO _x	氧空位	热处理	VOCs	T₉₀ = 167℃	[67]
Ag-MnO _x	氧空位、阳离子空位	离子掺杂	VOCs	T₉₀ = 216℃	[68]
Fe-CeO₂	氧空位	离子掺杂	VOCs	> 98%	[69]
Co₃O₄-ZrO₂	氧空位	离子掺杂	VOCs	90%	[70]
MnO _x	氧空位	热处理	VOCs	95%	[71]

金属氧化物种类	缺陷类型	制备方法	应用	性能	文献
UO₂	氧空位	还原法	含硫气体	—	[48]
Ce_1-_x Zr _x O₂	氧空位	离子掺杂	含硫气体	—	[49]
Cu₂O	氧空位	还原法	含硫气体	—	[37]
Au/CeO₂	氧空位	离子掺杂	含硫气体	—	[50]
NiO/ACF	阳离子空位	热处理	含硫气体	23.65 mg_s/g脱硫剂	[51]
Mn-TiO₂	氧空位	还原法	含硫气体	0.40 ± 0.05（相对浓度）	[52]
ZnO	氧空位	热处理	NO _x	36.7%	[53]
TiO₂	氧空位	热处理	NO _x	—	[54]
Zn₂SnO₄	氧空位	离子掺杂	NO _x	62%	[55]
Ce-SnO₂	氧空位	离子掺杂	NO _x	5.001 μmol/(g·h)	[56]
MnFeO _x /TiO₂	氧空位	还原法	NO _x	> 80%	[57]
Bi₂WO₆	氧空位	离子掺杂	NO _x	64%	[58]
ZnO	氧空位	热处理	NO _x	55.45%	[59]
Cu₂O	氧空位	还原法	CO₂	35.4%（法拉第效率）	[60]
TiO₂-Cu _x O	氧空位、阳离子空位	离子掺杂	CO₂	—	[61]
Bi₄Ti₃O₁₂	氧空位、阳离子空位	还原法	CO₂	4.90 μmol/(g·h)	[62]
ON-CuO	氧空位、面缺陷	离子掺杂	CO₂	56%（法拉第效率）	[44]
Cu/Co₃O₄	氧空位	离子掺杂	CO₂	99%	[63]
TiO₂	氧空位	热处理	CO₂	20.2%	[64]
Cu₂O	线缺陷、面缺陷	还原法	CO₂	48.3%（法拉第效率）	[65]
CeO₂-MgO	氧空位	热处理	VOCs	90%	[66]
MnO _x	氧空位	热处理	VOCs	T₉₀ = 167℃	[67]
Ag-MnO _x	氧空位、阳离子空位	离子掺杂	VOCs	T₉₀ = 216℃	[68]
Fe-CeO₂	氧空位	离子掺杂	VOCs	> 98%	[69]
Co₃O₄-ZrO₂	氧空位	离子掺杂	VOCs	90%	[70]
MnO _x	氧空位	热处理	VOCs	95%	[71]