The use of products from CO2 photoreduction for improvement of hydrogen evolution in water splitting

✍ Scribed by Xiaoyi Yang; Tiancun Xiao; Peter P. Edwards

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 582 KB
• Volume: 36
• Category: Article
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2011.02.116

✦ Synopsis

CuO/TiO 2 photocatalysts were prepared and shown to enhance the rate of CO 2 photoreduction and the production of total organic carbon (TOC), including HCOOH, HCHO and CH 3 OH. Resulting TOC could act as electron donors for enhancing visible light hydrogen evolution from Pt/TiO 2 photocatalysts. The impacts on CO 2 photoreduction were investigated including the effect of Cu dopant, pH, irradiation time and using Na 2 SO 3 as a sacrificial agent, and those on hydrogen evolution was also studied including TOC concentration and Pt doping. The CO 2 photoreduction mechanisms with respect to pH and CO 2 reduction potentials were discussed. CuO/TiO 2 and Pt/TiO 2 photocatalysts were characterized by X-ray diffraction, Raman spectroscopy and diffuse reflection UVevis spectrophotometry. Both photocatalysts showed a visible light response in comparison with pure TiO 2 . The photocatalytic experiments and FT-IR spectra indicated that photoproduct desorption was the rate-limiting step in the CO 2 photoreduction.