Construction of a red phosphorus-molybdenum dioxide electron-rich interface for efficient photocatalytic reduction of carbon dioxide.

Developing efficient catalysts to enhance photoreduction carbon dioxide (CO) into hydrocarbon fuels is a great challenge. As metallic material, molybdenum dioxide (MoO) has very high conductivity and charge density, which make it a promising candidate as photocatalyst. However, its photocatalytic activity is limited by the serious charge recombination. How to effectively make full use of the metallic MoO for photocatalytic CO reduction is still a critical issue. The potential effective way to solve this problem is to introduce appropriate auxiliary catalysts to construct electron-rich interfaces. In this study, red phosphorus (P) is dispersed on MoO nanoparticles to construct electron-rich interfaces which can serve as the active site for photocatalytic CO reduction. The results show that the reduction of CO by pure MoO only produces carbon monoxide (CO) and methane (CH). However, with the aid of red P, the P-MoO photocatalyst can produce ethylene (CH) with the yield of 5.43 μmol h g, and the CO and CH yields are also significantly improved. Experimental results and density functional theory (DFT) calculations indicate that photogenerated carriers can migrate from MoO to the interface, and the reduction of CO occurs at the interface. This study provides a significant insight for the design of efficient photocatalysts by using metallic photocatalysts.