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Hierarchically porous reduced graphene oxide/SnIn 4 S 8 (RGO/SnIn 4 S 8 ) composites with visible-light response and strong mineralization ability were first successfully prepared by a facile low-temperature co-precipitation method, and were characterized by X ray diffraction (XRD), scanning electron microscope (SEM), Brunauer-Emmet-Teller (BET), UV-Visible spectrophotometer (UV-Vis), Raman spectra and Photoluminescence (PL) techniques. RGO/SnIn 4 S 8 composite exhibits strong absorption in UV and visible-light range. The optimized 5% RGO/SnIn 4 S 8 possesses the optimal photocatalytic degradation efficiency and the best mineralization performance with complete degradation of Rhodamine B (RhB) within 70 min and 73.17% mineralization yield within 160 min under visible-light irradiation, which is much higher than that of pure SnIn 4 S 8 . The main reactive species, which play crucial roles in the degradation and mineralization of RhB, follow the order of h + >¨O 2´>¨O H. The intermediate products of RhB degradation were analyzed by using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS), and the possible degradation pathways and mechanism were proposed. Moreover, 5% RGO/SnIn 4 S 8 exhibits excellent reusability and stability without an obvious decrease in photocatalytic activity after four consecutive photocatalytic degradation-regeneration experiments.

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A series of two-dimensional (2D) interlaced BiOCl/carbon quantum dot composites (denoted as BiOCl/CQD composites) were synthesized by a template-free coprecipitation method at room temperature, and the influence of different particle size distributions of the CQDs on the physiochemical properties and photocatalytic activities of the BiOCl/CQD composites was studied. CQDs can change the morphology and increase the specific surface area of the BiOCl/CQD composites. Moreover, the particle size distribution of the CQDs (CQD loading amount) has some effect on the light absorption, separation of photogenerated charge carriers, and photocatalytic performance of  the BiOCl/CQD composites. The optimized size distribution of the CQDs is 50-150 nm. BiOCl/CQD (50-150 nm) composites showed the best improvement of light absorption and the highest photocurrent density of 0.44 μA cm(-2), and exhibited the highest photocatalytic activity with almost 100% 2-nitrophenol removal under visible-light irradiation. The high efficacy of BiOCl/CQD (50-150 nm) composites could be attributed to their excellent light absorption and highly effective separation of photogenerated charge carriers.