Tailoring of orderly CeO2/Pt loaded Ti4O7 reactive electrochemical membranes for efficient electrooxidation of antimicrobial dichlorophen

Limited electrooxidation efficiency and high energy consumption restrict the application of Ti4O7 reactive electrochemical membrane (REM). This study aimed to improve the electrooxidation reactivity of Ti4O7 REM through tailoring CeO2 transition layer into the interface of Ti4O7 loaded with Pt. We found that 1Pt/CeO2-Ti4O7 REM (1 wt% Pt) operation in single pass achieved more than 31 times enhancement for dichlorophen (DCP) removal rates compared with pristine Ti4O7 at 0.5 mA cm-2, accompanied by over 98 % energy consumption reduction. Characterization results showed that CeO2 loaded on Ti4O7 could uniformly disperse Pt clusters by anchoring effect on Pt atoms to exhibit stable and efficient electrooxidation activity. Density functional theory simulations and well-designed experiments elucidated that direct electron transfer (DET) anodic oxidation drove the electrooxidation process of DCP in Pt/CeO2-Ti4O7 REM due to the increased charge transfer efficiency, active sites and the adsorption energy for DCP. This differs from the joint action of DET reaction and hydroxyl radicals mediated reaction in pristine Ti4O7 anode. More pronounced charge redistribution and accumulation at DCP-Pt/ CeO2-Ti4O7 interface especially around Cl atoms facilitated nucleophilic substitution of the hydroxyl group for Cl atoms to realize less containing chlorine intermediate products and greater mineralization rates. These findings provide insights into interface engineering strategies for preparing Ti4O7 REM with excellent reactivity and low energy consumption.