Coaxial Fe2O3/TiO2 nanotubes for enhanced photo-Fenton degradation of electron-deficient organic contaminant

• 作者: Yue Li Dan-Dan Cheng Yan Luo Li-Xia Yang
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2021,（12）
• 所属期刊栏目: ORIGINAL ARTICLES
• 页码范围: 3543-3553
• 页数: 11页
• 语种: 英文

摘要

Coaxial FezO3/TiO2 nanotubes (Fe2O3/TiO2 NTs) were prepared by two anodic oxidation processes.The synthesized Fe2O3/TiO2 NTs catalysts showed high photocatalytic activity in heterogeneous photo-Fenton system.With the help of Fe2O3/TiO2 NTs,4-nitrophenol(10 mg·L-1,50 ml),a typical electron-deficient organic contaminant,can be completely removed by adding only 0.4 mmol·L-1 of H2O2 under irradiation.Investigation results clarify that the calculated position of Fe2O3/TiO2 NTs valence band is at 2.944 eV,its potential is higher than the potential of OH-/OH (2.800 eV),thereby ensur-ing the generation of OH.Meanwhile,the transformation of photogenerated electrons from the conduction band of TiO2 to Fe2O3 accelerates the reduction of Fe3+ to Fe2+.The unstable Fe2+ can be oxidized by H2O2 to produce high yields of OH.Therefore,both the coaxial hetero-junction and fast Fe2+/Fe3+ conversion provide abundant OH to effective attack the electron-deficient benzene ring passivated by the nitro group.Thus,surface-catalyzed degradation of 4-nitrophenol can be carried out step by step.This work contributes a detailed understanding of charge transfer in semiconductor composites and degra-dation of organic contaminants.