Efficient Conversion of CO2 to Methane Photocatalyzed by Conductive Black Titania

5 years ago

Efficient Conversion of CO2 to Methane Photocatalyzed by Conductive Black Titania

Tianquan Lin, Guoheng Yin, Jijian Xu, Qingyuan Bi, Fuqiang Huang, Wei Zhao

One of the major challenges encountered in CO2 utilization is the development of available and cost-efficient catalysts with sufficient activity, selectivity, and stability for the generation of useful methane. Here, conductive black titania, TiO2−x, is found to be efficient in photocatalyzing the reduction of CO2 to CH4. This unique material comprises a crystalline core–amorphous shell structure (TiO2@TiO2−x) with numerous surface oxygen vacancies, which facilitates the adsorption and chemical activation of CO2 molecules. Under full solar irradiation, the optimized 500-TiO2−x material with narrowed band gap and intermediate states below the conduction band tail exhibits a high space-time yield of CH4 of 14.3 μmol g−1 h−1, with 74 % selectivity and excellent photostability. The present findings can make a significant contribution, not only to develop the surface electron-modified black TiO2 catalyst to boost photocatalytic efficiency, but also to establish a really viable and convenient CH4 production process for CO2 conversion and renewable solar energy storage. Back in black: Conductive black TiO2 (TiO2@TiO2−x) with crystalline core–amorphous shell structure achieves high efficiency for photoinduced reduction of CO2 to CH4, presenting an efficient and reliable route to CO2 conversion and solar energy storage.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/cctc.201701130