Enhanced photocatalytic degradation of organic contaminants over CaFe2O4 under visible LED light irradiation mediated by peroxymonosulfate

• 作者: Sheng Guo Zhixiong Yang Huali Zhang Wei Yang Jun Li Kun Zhou
• 来源期刊: 材料科学技术（英文版）
• 年，卷（期）: 2021,（3）
• 页码范围: 34-43
• 页数: 10页
• 语种: 英文

摘要

A simple sol-gel approach is proposed herein to fabricate Ca Fe2O4 for the degradation of various organic pollutants (rhodamine B (RhB),tetracycline hydrochloride,humic acid,and methylene orange) under LED light irradiation mediated by peroxymonosulfate (PMS).The results indicate that the calcination temperature can significantly influence the performance of CaFe2O4 for PMS activation,and the CaFe2O4 sample obtained at 800 ℃ (CaFe2O4-800) exhibits the best efficiency in degrading RhB,which is much higher than that of Fe2O3-800.This can be attributed to the efficient separation of photogenerated electrons (e) and holes (h+) by PMS,which is validated by transient photocurrent response and photoluminescence measurements.Results from density functional theory calculations indicate that the valence band of CaFe2O4-800 exhibits a high concentration of carriers and weak localization of electrons,which are favorable for PMS activation.Radical scavenging results confirm that h+ and O2·-are the dominant reactive species.Moreover,CaFe2O4-800 not only demonstrated a stable performance during eight cycling runs with negligible iron leaching but also exhibited excellent degradation efficiency under natural water and sunlight.Finally,the mechanism and pathway of RhB degradation by the CaFe2O4-800/PMS/LED system are also proposed.This work presents the enormous prospect of CaFe2O4 as an environmentally benign photocatalyst for PMS activation.