Fe doped g-C3N4 composited ZnIn2S4 promoting Cr(Ⅵ) photoreduction

30% Fe CN/ZIS(30% Fe doped g-C3N4composited ZnIn2S4) was synthesized by a simple water bath method, via in-situ growth of abundant well-dispersed ZnIn2S4nanosheets on the Fe doped g-C3N4surface. Experimental results showed the optimized 30% Fe CN/ZIS achieved the best photoreduction of Cr(VI)performance within a wide p H range, which was 9.5 times and 700 times higher than that of pure ZnIn2S4and 30% Fe CN(Fe doped g-C3N4). This is due to the intense synergy between the Fe-Nxbond and close interface contact produces a high-speed charge transfer channel, thus significantly improving the efficiency of optical carrier separation and migration. Meanwhile, UV-vis diffuse reflection spectra and photoluminescence spectroscopy showed that iron doping significantly narrowed the bandgap of gC3N4, preventing electron-hole pair recombination. Further, the microstructures and charge separation properties were analyzed by scanning electron microscope, Photoluminescence Spectroscopy and timeresolved photoluminescence, which revealed the structure-activity relationship of composite structure and the synergistic mechanism of each functional component. This research should provide a viable technique for creating composites with high photocatalytic activity for the treatment of chromium-containing wastewater.