Interface engineering strategy of a TiO ceramic membrane via graphene oxide nanoparticles toward efficient electrooxidation of 1,4-dioxane.

Although TiO ceramic membrane has been recognized as one of the most promising anode materials for electrochemical advanced oxidation process (EAOP), it suffers from relatively low hydroxyl radical (OH) production rate and high charge-transfer resistance that restricted its oxidation performance of organic pollutants. Herein, we reported an effective interface engineering strategy to develop a TiO reactive electrochemical membrane (REM) doped by graphene oxide nanoparticles (GONs), GONs@TiO REM, via strong GONs-O-Ti bonds. Results showed that 1% (wt%) GON doping on TiO REM significantly reduced the charge-transfer resistance from 73.87 to 8.42 Ω compared with the pristine TiO REM, and yielded OH at 2.5-2.8 times higher rate. The 1,4-dioxane (1,4-D) oxidation rate in batch experiments by 1%GONs@TiO REM was 1.49×10 min, 2 times higher than that of the pristine TiO REM (7.51×10 min) and similar to that of BDD (1.79×10 min). The 1%GONs@TiO REM exhibited high stability after a polarization test of 90 h at 80 mA/cm, and within 15 consecutive cycles, its oxidation performance was stable (95.1-99.2%) with about 1% of GONs lost on the REM. In addition, REM process can efficiently degrade refractory organic matters in the groundwater and landfill leachate, the total organic carbon was removed by 54.5% with a single-pass REM. A normalized electric energy consumption per log removal of 1,4-D (EE/O) was observed at only 0.2-0.6 kWh/m. Our results suggested that chemical-bonded interface engineering strategy using GONs can facilitate the EAOP performance of TiO ceramic membrane with outstanding reactivity and stability.