Noble metal-free MoS2-modified In2S3 for excellent visible-NIR-light-driven photocatalytic of Cr6+ removal in alkaline wastewater

MoS 2 -modified In 2 S 3 ( x wt.%MoS 2 -In 2 S 3 ) samples (0 ≤  x  ≤ 20) were fabricated through a facile one-pot hydrothermal process. All In 2 S 3 samples modified by MoS 2 deliver an excellent Cr 6+ removal ability under visible-NIR-light-driven, and 5% MoS 2 -In 2 S 3 can reduce 20 mg/L Cr 6+ solution completely within 30 min with a trace photocatalyst concentration (0.27 mg/mL) which is 3.2-hold higher than that of single In 2 S 3 . Further investigations demonstrate that the loaded MoS 2 can not only enhance the absorption of light scope but also promote the interfacial electron transfer from In 2 S 3 to MoS 2 and then to Cr 6+ , thus greatly improving the Cr 6+ removal ability. ESR shows that the modifying of MoS 2 can accelerate the transformation of electrons from the In 2 S 3 to MoS 2 which results in that the intensity of O 2 − • significantly increased. PL, photocurrent, and EIS further identified that the modification of MoS 2 can greatly improve the charge carrier separation efficiency. The fabricated MoS 2 -In 2 S 3 samples also exhibit characteristic features such as stable and reducing Cr 6+ in the weak alkaline environment for the first time, which could always be a great challenge for wastewater purification in alkaline condition.