Photoelectrocatalytic Synergistic Degradation Of Organic Pollutants

Photoelectrocatalysis is an efficient catalytic oxidation technology that combines photocatalysis and electrocatalysis,promoting the separation of electron-hole pairs more efficiently under external electric field.Titanium dioxide?TiO₂?is the traditional semiconductor catalytic material with advantages such as non-toxic,harmless,easy to obtain,and chemically stable.However,the wide band gap and the low utilization of light for TiO₂ limited its wide application.The surface modification,water bath method,and photochemical chemical method were respectively used to modify TiO₂ to improve the photocatalytic performance of TiO₂.A graphene-polyaniline/titanium dioxide?rGH-PANI/TiO₂?composite gel electrode was prepared,which possess large specific surface area and fixed more TiO₂,solving the problem of difficult recovery of catalyst and improving pollutant adsorption and degradation ability.The composite gel electrode exhibited high catalytic degradation activity towards phenol,bisphenol A?BPA?,2,4-dichlorophenol,and coking wastewater.After degradation by photoelectrocatalysis?PEC?for 8 h,the degradation efficiency for pollutants could reach 100%.Simultaneously,the quenching experiment showed that holes?h⁺?and superoxide radicals(·O^2-)were the main active substances.The efficient degradation ability of the rGH-PANI/TiO₂ is mainly due to the rapid adsorption and in-situ degradation of pollutants.In order to further improve the separation efficiency of TiO₂ for e^-/h⁺,the noble metal Ag nanoparticles was employed to modify TiO₂ to increase the absorption range of TiO₂ for visible light and effectively reduce the recombination of e^-/h⁺.The photocurrent density of Ag-TNTA-1 was 1.85 times higher than that of TNTA by testing its photoelectric performance.The degradation efficicency of Ag-TNTA-1 for phenol could reach 100%at 240 min.The gel and the nanotube photoelectrodes can be well separated from the water body,improving the utilization of the catalyst and avoiding secondary pollution.Simultaneously,these composite catalysts exhibited excellent photocatalytic activity for BPA,phenol,2,4-dichlorophenol,and coking wastewater.Figure 36;Table 3;Reference 114...