High-efficiency photoreduction of CO in a low vacuum.

Photoreduction of CO into CO, CH or hydrocarbons is attractive, due to environmental compatibility and economic feasibility. Optimizing the reaction engineering of CO reduction is an effective and general strategy that should be given special consideration. In this article, the photocatalytic CO reduction performances are originally investigated in a low vacuum in both dilute (10%) and pure CO. We discover that the CH yield increased above one hundred times as the vacuum degree increased from barometric pressure to -80 kPa in dilute CO. It also reveals long-term stability and good cycling performance in a low vacuum. The enhanced CO photoreduction performance in a low vacuum comes from better accumulation of photogenerated electrons, less intense Brownian movement of gas molecules in the environment and hindrance of the active site-blocking of gas molecules in the environment. Improved photocatalytic CO reduction in a low vacuum is further verified by Pt-TiO catalysts. This research presents a general route for producing clean fuels by photocatalytic CO reduction in a more effective way.