Structurally-controlled FeNi LDH/CNTs electro-Fenton membrane for in-situ electro-generation and activation of hydroxyl radicals toward organic micropollutant treatment

Designing a highly-active electro-Fenton membrane (EFM) and understanding how its microstructure controls its catalytic activity is vital for organic micropollutants treatment. Herein, an EFM based on the in-situ growth of vertical FeNi layered double hydroxide catalyst on a carbon nanotube membrane (FeNi LDH/CNTs) was con-structed. The & BULL;OH catalytic activity was tailored by altering the structure and composition of the key active component, FeNi LDH. The results showed that the optimal Fe1Ni1 LDH with a highly-ordered porous honeycomb structure endowed the Fe1Ni1 LDH/CNT membrane with superior catalytic activity and favorable phenol removal efficiency (86%). The highly-ordered vertical nanosheets of Fe1Ni1 LDH made the active sites fully exposed to proceed the redox cycling of Fe3+/Fe2+ and further catalyzed & BULL;OH. The porous CNT substrate catalytically produced H2O2 and greatly enhanced the mass transfer efficiency. This study provides new insights into exploring the effect of the catalyst structure and composition on the performance of functionalized EFMs.

Automated summary

Designing a highly-active electro-Fenton membrane and understanding the influence of catalyst microstructure on its catalytic activity are crucial for the treatment of organic micropollutants. In this study, an EFM based on FeNi layered double hydroxide catalyst grown on a carbon nanotube membrane was constructed. By controlling the structure and composition of the catalyst, the catalytic activity of FeNi LDH/CNTs was optimized. The results demonstrated that the highly-ordered porous honeycomb structure of Fe1Ni1 LDH contributed to superior catalytic activity and efficient phenol removal.