The solvent-driven formation of multi-morphological Ag–CeO2 plasmonic photocatalysts with enhanced visible-light photocatalytic reduction of CO2

Abstract

Ag–CeO₂ plasmonic photocatalysts with multiple morphologies were synthesized via a simple solvent-driven method. The phase compositions, morphologies and optical properties of the samples were systematically investigated. A combination of noble metal Ag and semiconductor CeO₂ in certain solvents (such as methanol and ethylene glycol) enhanced surface plasmon resonance (SPR), which was attributed to the good dispersion of Ag particles on CeO₂ and high Ag⁰ ratios on the surface. The enhanced SPR effect boosted absorption of incident light and facilitated charge carrier separation and transport efficiency caused by the formation of Schottky barriers, thus promoting VLPCR performance. The optimum ACG sample (ethylene glycol was adopted as the solvent) exhibited the maximum VLPCR activity, achieving a CH₄ yield of 100 μmol and a CH₃OH yield of 35 μmol per gram of catalyst per hour during 6 h visible-light irradiation.