In situ construction of Z-scheme FeS2/Fe2O3 photocatalyst via structural transformation of pyrite for photocatalytic degradation of carbamazepine and the synergistic reduction of Cr(Ⅵ)

• 作者: Qian Guo Guangbei Tang Wenjie Zhu Yongming Luo Xiaoya Gao
• 来源期刊: 环境科学学报（英文版）
• 年，卷（期）: 2021,（3）
• 页码范围: 351-360
• 页数: 10页
• 语种: 英文

摘要

Pyrite is the most abundant sulfide semiconductor mineral with excellent optical proper-ties.However,few reports have investigated its photocatalytic activity because of the low photogenerated carrier separation efficiency.In this work,a Z-scheme FeS2/Fe2O3 com-posite photocatalyst was fabricated in situ via structural transformation of pyrite through heat treatment.A remarkably enhanced photocatalytic performance was observed over the FeS2/Fe2O3 composite photocatalyst.Compared with the pristine pyrite,the degradation ef-ficiency of carbamazepine(CBZ)reached 65％at the added hexavalent chromium(Cr(Ⅵ))concentration of 20 mg/L and the Cr(Ⅵ)was nearly completely reduced in the mixed sys-tem using FeS2/Fe2O3 within 30 min under simulated solar light irradiation.The enhanced photocatalytic activity can be attributed to the efficient separation and transfer of photogen-erated carriers in the FeS2/Fe2O3 composite photocatalyst.This facilitated the generation of?OH,hole(h+)and ?O2-species,which participated in the photocatalytic reaction with CBZ.Based on the measurement of the active species and electric properties,a Z-scheme elec-tron transfer pathway was proposed for the FeS2/Fe2O3 composite photocatalyst.This work broadens the application potential of pyrite in environmental remediation.