Photocatalytic Degradation of Gaseous Acetone by a Self-prepared Nano-sized Composite TiO_2/In_2O_3/SnO_2 Film Photocatalyst

摘要

The objective of this study is to decompose gaseous acetone ((CH_3)_2CO) by a self-prepared nano-sized composite TiO_2/In_2O_3/SnO_2 film photocatalyst that was prepared by a multi-target vacuum sputter operating at a vacuum pressure of 3 mtorr. The operating parameters investigated for the sputtering process included oxygen to argon ratio (O_2/Ar), sputtering temperature, substrate materials, substrate layers, and sputtering duration. The nano-sized composite TiO_2/In_2O_3/SnO_2 film photocatalyst was mainly composed of anatase with a few rutile. The surface roughness of the TiO_2/In_2O_3/SnO_2 film photocatalyst in terms of RMS ranged from 2.292 to 7.533 nm, while the thickness of the single- and double-layer film photocatalysts were 473.5 and 506.0 nm, respectively. Gaseous acetone was initially injected into and further degraded in a self-designed batch photocataiytic reactor containing the nano-sized composite TiO_2/In_2O_3/SnO_2 film photocatalyst. Experimental results indicated that the highest acetone degradation efficiency of 99.9% was obtained at 50°C and 1 atm with the incident of near-UV illuminated by a fluorescent black light lamp. Under the incidence of blue light (430-500 nm), the reaction rates of acetone decomposition were 2.353 x 10~(-5) and 3.478 x 10~(-5) μmole/cm~2-sec for using single- and double-layer TiO_2/In_2O_3/SnO_2 film photocatalysts, respectively.