Synthesis and Visible-Light Photocatalytic N2/H2O to Ammonia of Au@CDs Core-Shell Nanocatalyst

Abstract

Synthesis and visible-light photocatalytic N2/H2O to ammonia at atmospheric pressure and room temperature is considered to be the most ideal ammonia synthesis technology. In this study, coal-based carbon dots (CDs) were prepared by H2O2 oxidation method using cheap and ubiquitous coal as the carbon source. Then the gold sol was connected to CDs to obtain a core-shell structure photocatalyst Au@CDs by sodium borohydride (NaBH4) reduction method. While characterizing the material structure, the photocatalytic N2/H2O to ammonia performance of Au@CDs was investigated. The results show that the introduction of CDs in Au @CDs photocatalysts can not only improve the performance of the catalyst to excite carriers in visible light, but also inhibit the recombination of photogenerated electron-hole pairs, promote the charge transport ability and make photogenerated electrons and holes move smoothly to the catalyst surface. Meanwhile, the adsorption and dissociation capacity of N2 on the catalyst surface can be improved, thereby the photocatalytic N2/H2O ammonia synthesis reaction of Au@CDs can proceed smoothly.