Silver-Loaded In2s3-Cdin2s4@X(X=Ag, Ag3po4, Agl) Ternary Heterostructure Nanotubes Treated By Electron Beam Irradiation With Enhanced Photocatalytic Activity

Ternary heterostructure nanotubes of In2S3-CdIn2S4@X(X Ag, Ag3PO4, AgI) were synthesized with enhanced photocatalytic activity for efficiently degrading pollutants. Electron beam irradiation was employed to artificially introduce interface defects to the heterostructure nanotubes. The experimental results for degrading carmine and Cr6 under visible light irradiation showed that the photocatalytic efficiency of In2S3-CdIn2S4 was improved to some extent by the introduction of silver compounds. DRS results confirmed that the band gaps of In2S3-CdIn2S4 were reduced to 1.62 eV and 1.58 eV by introducing Ag3PO4 and Agl, respectively. Interestingly, the band gap of In2S3-CdIn2S4@Agl after electron beam irradiation was further reduced to 1.56 eV, resulting in that the degradation time of both Cr6 and carmine by In2S3-CdIn2S4@Agl after high-energy electron beam irradiation was shortened to only 5 min. The XRD spectra of the photocatalysts after five cycles could maintain the original crystal form to a large extent. The O-H stretching vibration peaks of In2S3-CdIn2S4@Agl after electron beam irradiation at 3387 cm I became wider and sharper, thus indicating that the number of free hydroxyl groups on the heterostructure surface significantly increased. PL results showed that electron beam irradiation could significantly reduce the PL e mission peak and enhance the utilization of photogenerated charge carriers. EIS results further confirmed that In2S3-CdIn2S4@Agl processed by electron beam irradiation had higher photogenerated electron-hole separation efficiency. Based on the experimental results, a feasible reaction pathway and photocatalytic mechanism for the degradation of carmine was investigated. ESR results showed that the main active groups in the whole photocatalytic system were center dot O-2(-) and h(+). (C) 2019 Elsevier B.V. All rights reserved.