Novel metal-organic framework/stannous sulfide (MIL-53(Fe)/SnS) nanocomposite photocatalysts were successfully synthesized by a one-step deposition process. The structure, composition and optical properties of the MIL-53(Fe)/SnS composite were systematically characterized by the X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, Fourier transform-infrared spectroscopy, UV–vis diffuse reflection spectroscopy and photoluminescence analysis. The photocatalytic performance of MIL-53(Fe)/SnS composite has been evaluated in the reduction of chromium (VI) under visible-light irradiation. Compared with pure MIL-53(Fe) and SnS, the MIL-53(Fe)/SnS composite exhibited enhanced photoreduction capability of chromium (VI) due to the strengthened absorption in the visible region, higher electron-hole separation rate and larger specific area. The MIL-53(Fe)/SnS composite with MIL-53(Fe) adding of 15 mg displayed optimal chromium (VI) reduction rate of 0.01878 min⁻¹, which was about 7.5 and 5.2 times than pure MIL-53(Fe) and SnS, respectively. The active species superoxide radical (O₂^–), electron(e⁻) and hole(h⁺) are essential toward chromium (VI) reduction. Lastly, a possible photocatalytic mechanism is proposed.

通过一步沉积工艺成功地合成了新型金属有机骨架/硫化亚锡（MIL-53（Fe）/ SnS）纳米复合光催化剂。通过X射线衍射，X射线光电子能谱，扫描电子显微镜，透射电子显微镜，傅立叶变换红外光谱，UV-可见漫反射光谱和光致发光分析。已在可见光照射下通过还原铬（VI）评估了MIL-53（Fe）/ SnS复合材料的光催化性能。与纯MIL-53（Fe）和SnS相比，MIL-53（Fe）/ SnS复合材料由于在可见光区的吸收增强而显示出增强的铬（VI）的光还原能力，更高的电子-空穴分离率和更大的比表面积。加入15 mg MIL-53（Fe）的MIL-53（Fe）/ SnS复合材料显示的最佳铬（VI）还原速率为0.01878分钟^-1，分别是纯MIL-53（Fe）和SnS的7.5倍和5.2倍。活性种超氧阴离子自由基（ö ₂ ^- ），电子（E ^- ）和孔（H ⁺）是朝向铬（VI）还原是必不可少的。最后，提出了一种可能的光催化机理。