TiO₂/SiO₂ Composite Films Immobilized on Foam Nickel Substrate for the Photocatalytic Degradation of Gaseous Acetaldehyde

Table 1

Comparison of surface characteristics and photocatalytic behaviors of various TiO₂ and TiO₂/SiO₂ films immobilized on foam nickel.

Sample	Surface characteristics			Degradation ratio of acetaldehyde in
	SSA of modified substrate (m^2g^−1)^a	SSA of the sample (m^2 g^-1)	TiO2 weight ratio (%)^b	90 min (%)^c
T1	0.24	0.7	5	35
T2	0.24	0.9	8	62
S1T1	167.2	70.6	4.2	42
S1T2	167.2	35.4	6.6	70
S2T1	159.4	56.0	4.1	80
S2T2	159.4	32.9	7.8	92

^aThe foam nickel substrate was modified by preheating treatment (550^°C for 10 minutes) for T1 and T2, and coating SiO₂ as transition layer for S1T1, S1T2, S2T1, and S2T2 before loading TiO₂. The S1 was regarded as modified substrate for S1T1 and S1T2, and S2 as that of S2T1 and S2T2.^bCalculated according to 𝑅=(𝑊_𝑡/𝑊_ms)×100%, where 𝑅 is the weight-increment ratio of TiO₂, 𝑊_𝑡 denotes the weight of loaded TiO₂, and 𝑊_ms is the weight of modified substrate.^cGaseous acetaldehyde in 100 ppmv of 1000 cm³. A UV-light lamp (𝜆=254nm,15W) was applied as light source.