Transfer Charge and Energy of Ag@CdSe QDs-rGO Core-Shell Plasmonic Photocatalyst for Enhanced Visible Light Photocatalytic Activity

Plasmonic heteronanostructures in semiconductor type display extraordinary photocatalytic efficiency induced by the plasmonic energy that operates in the Ag@CdSe-rGO hybrid ternary composites. The obtained plasmonic photocatalysts in nanoscale were fabricated by using a one-step hydrothermal method, during which the in situ nucleation of Ag@CdSe core-shell nanoparticles and the reduction of GO to rGO occurred simultaneously. Three different roles of Ag core and the junction of synergistic properties arising from the introduced rGO jointly enhanced the optical properties of CdSe. Localized plasmon resonance (LPR) effects of plasmonic Ag contribute to the separation of photogenerated e^-/h⁺ pairs via the electrons and resonant energy transfer. Electrochemical investigations have further confirmed the enhanced separation of the photogenerated e^-/h⁺ pairs. From comparative photocatalytic experiments of Ag@CdSe-rGO and Ag/CdSe-rGO, the plasmonic effect of the Ag core in the Ag@CdSe-rGO nanostructure serves to prolong the charge separation under visible light beyond common attached trimers.