Enhancement of the photoelectrocatalytic activity of TiO2/ACF for ethylene removal by Ag nanoparticles synthesized by γ-ray radiolysis

Silver nanoparticles (AgNPs), obtained by reduction from AgNO3 solution and stabilized in polyvinyl pyrrolidone (PVP), have been synthesized by γ-ray radiolysis. The application of photoelectrocatalytic (PEC) oxidation in ethylene gas treatment using a TiO2 photocatalyst combined with as-prepared AgNPs on activated carbon fiber (ACF) ([Ag+TiO2]/ACF) as a photoelectrode in a Nafion-based photoelectrocatalytic cell is presented. The effects on the PEC degradation of C2H4 of the preparation parameters of the AgNPs, such as the radiation dose and the amount of PVP added, have been systematically investigated. Emphasis is placed on comparison of the C2H4 decomposition rate constant with [Ag+TiO2/ACF] as a photoelectrode in a photoelectrocatalytic cell with that achieved with [TiO2/ACF]. The factors responsible for the enhancing effect of AgNPs on the PEC activity of the [Ag+TiO2/ACF] photoelectrode are discussed.