Simultaneous Elimination of Formaldehyde and Ozone Byproduct Using Noble Metal Modified TiO₂ Films in the Gaseous VUV Photocatalysis

Table 1

The outlet concentration and removal rates of HCHO and O₃, and reaction rates of HCHO in the 35 h VUV, O₃ + UV_254 nm, and UV_254 nm photocatalysis, respectively.

Kinds of photocatalysis	Photocatalysts	Formaldehyde			Ozone
		Concentration; (ppbv)	Removal rate; (%)	Reaction rate; (mg/m^3·min)	Concentration; (mg/m^3)	Removal rate; (%)
VUV photocatalysis	VUV photolysis	122.4	72.9	1.16	22.4	0
	TiO2	36.1	91.4	1.34	19.2	14.3
	Pd-TiO2	20.1	95.3	1.43	14.2	36.6
	Pt-TiO2	9.5	97.7	1.47	10.7	52.2
	Au-TiO2	27.6	93.6	1.41	15.1	32.6
O3+UV254nm photocatalysis	TiO2	178.8	57.4	0.85	13.8	37.8
	Pd-TiO2	150.1	65.7	0.96	9.3	58.1
	Pt-TiO2	125.1	68.6	1.01	6.2	72.1
	Au-TiO2	130.6	68.8	1.02	10.8	51.4
UV254nm  photocatalysis	TiO2	263.4	37.8	0.57
	Pd-TiO2	251.3	37.6	0.56
	Pt-TiO2	190.6	56.7	0.89
	Au-TiO2	218.1	45.2	0.63