Preparation of WO3/In2O3 heterojunctions and their performance on the CO2 photocatalytic conversion in a continuous flow reactor
M. Chico-Vecino, J.C. Murillo-Sierra, D.A. Pino-Sandoval, Laura Hinojosa‐Reyes, María de Lourdes Maya-Treviño, David Contreras, Aracely Hernández‐Ramírez
Abstract
This study investigated the CO 2 conversion in the gas phase using the WO 3 /In 2 O 3 photocatalysts synthesized by the solvothermal method at different WO 3 content (5, 10, and 15 wt%). The experimental results in a continuous flow reactor demonstrated that carbon monoxide was the main product obtained from the photocatalytic reduction of CO 2 using the coupled oxides and the individual semiconductors. However, in addition to CO, the WO 3 /In 2 O 3 catalyst also produced CH 4 and C 3 H 6 hydrocarbons. The incorporation of WO 3 into In 2 O 3 inhibits the crystal growth and changes the preferentially formed cubic phase of In 2 O 3 to the hexagonal phase structure, promoting the generation of hydrocarbons. The W 15% /In coupled catalyst exhibited the best performance on methane and propylene production. This behavior was attributed to the enhanced interaction between the gas and the catalyst surface, and the improved charge separation promoted by the direct Z-scheme mechanism in the W 15% /In heterojunction .