Paper Title
Photocatalytic Reduction of Carbon Dioxide to Methane Over Nio/Tio2 in Gas Phase Under Uv Light Illumination

Abstract
Pure TiO2 photocatalyst doped with nickel oxide (NiO/TiO2) was synthesized by impregnation method and coated on glass substrates used for reducing carbon dioxide in gas phase. The photocatalytic reduction of CO2 was conducted in a planar reactor under UV illumination with a light intensity of 25.34 mWcm-2in 90 min. The characterization of photocatalysts was observed by XRD, SEM, N2 adsorption–desorption, UV–vis. The effects of CO2 initial concentration, the relative humidity and the amount of NiO loading on the photoreduction process was investigated. The product, CH4 were formed in order: 10 wt% NiO/TiO2 > TiO2 > 20 wt% NiO/TiO2. In this study, the highest yield of CH4 was 401 ppm/gcatalyst in the optimal operation condition: 600 ppm initial concentration, 45 % relative humidity using 10 wt% NiO/TiO2. Index terms - Nio, Photocatalysis, P-N Junction, Tio2