Table 7.

Summary of catalytic activities in the VOC oxidation of reported metal oxide catalysts with hollow structures.

Catalysts	Synthesis Method	Textural Properties		Reaction Conditions	X (%)	T (°C)	Ref.
		SBET (m2g−1)	Pore Volume (cm3g−1)
KxMnO2 hollow nanospheres	Soft chemistry route	40.7	0.09	100 ppm HCHO, 20 vol % O2, GHSV = 50,000 h−1	80	100	[167]
MnO2 hollow spheres	Hard templating method	104.0~236.0	0.40~0.80	100 ppmv HCHO in dry air, GHSV 30,000 h−1	99.7	90	[23]
Au/MnO2 hierarchical hollow microsphere	Hydrothermal method and sol-gel method	52.3	0.16	200 ppm HCHO in air, GHSV 30,000 mL⋅g−1cat⋅h−1	59.2	25	[168]
Pt/C@MnO2 composite hierarchical hollow microspheres	Hydro- thermal method with hollow carbon spheres as a sacrificial template	153.0	0.37	HCHO solution (38% mass concentration)	90.5	__	[2]
Hierarchical Pt/WO3 nanoflakes assembled hollow microspheres	Solution method	23.0	0.12	HCHO solution (38% mass concentration), 260 ppm HCHO concentration	97	__	[165]
Hierarchically macro-mesoporous Pt/γ-Al2O3 composite hollow microspheres	Chemically induced self-transformation method	114.0	0.37	HCHO solution (38%)	__	__	[169]
Hierarchical Pt/NiO hollow microspheres	Template-free approach	50.8	0.11	HCHO solution (38%)	__	__	[170]
Pt/CoSn(OH)6 hollow nanoboxes	__	__	__	HCHO solution (38%), ~180 ppm HCHO concentration	80.1	__	[171]
Hollow chains mesoporous Pt/TiO2 (RPt-nominal were 0.5 wt%)	Microwave–hydrothermal route	132.0	0.29	HCHO solution (38%)	__	__	[145]
Fe2O3@SnO2 core–shell nanospindles	__	108.0	0.18	HCHO aqueous solution (38 wt%, contains 10–15 wt% methanol)	95.99	__	[172]
RuCoOx/Al2O3 hollow microspheres	Soft-template method	193.0	0.39	Gas containing 0.1% vinyl chloride in air, weight hourly space velocity (WHSV) of 30,000 mL·g−1·h−1	90	345	[166]