Photocatalysis enhancement of Au/BFO nanoparticles using plasmon resonance of Au NPs

BiFeO3 (BFO) nanoparticles was synthesized via sol-gel technique, and successfully loaded with small sizes of gold nanoparticles (Au NPs) by impregnation-reduction method to extremely enhance the BFO photocatalytic activity. The obviously stronger optical absorption of Au/BFO observed from the UV-vis diffuse reflectance spectrum confirmed that the surface plasmon resonance (SPR) effect occured on the surface of Au NPs. And the surface plasmon-induced localized electric field could allow the formation of electron/hole pairs in the near surface region of BFO which can migrate to the surface without undergoing electron/hole (e−/h+) pair recombination. The more electrons and holes formed, the more ·OH will be generated to decompose the CR solution. When the gold loading in Au/BFO nanoparticles is 3.36 wt%, the obtained Au/BFO catalyst exhibits best photocatalytic activity evaluated by photocatalysis degradation of Congo red (CR) solution under the visible light irradiation.