Strategic harmonization of silica shell stabilization with Pt embedding on AuNPs for efficient artificial photosynthesis†
Abstract
Highly efficient, stable, selective and durable photocatalysts for CO2 reduction systems are important to address the shortages of energy sources and carbon resources and to solve the global warming problem. Here, we report Pt–AuNPs@SiO2-mediated efficient full-spectrum photo-conversion of CO2 to HCOOH at room temperature. Three different morphologies of AuNPs with different controlled SiO2 shell thicknesses were prepared. Stabilization of the silica shell was achieved by embedding with PtNPs, which are an excellent co-catalyst with high selectivity for CO2 reduction. The prepared Pt–AuNPs@SiO2 nanocomplex showed high efficiency, with 1.79% quantum yield and 3.07% chemical yield for CO2 photo-conversion under visible light irradiation. The results highlighted the role of SiO2 and the embedding of Pt nanoparticles, which broadened the surface plasmon resonance band of the core AuNPs and enhanced the photoconversion efficiency. Pt–AuNPs@SiO2 demonstrated excellent colloidal, morphological, and photocatalytic stability, with 10 reaction recycles and a shelf-life of at least six months.