In every test, a known amount of G/M-CdS composite or CdS particles was added to 20 mL of dye solutions with the concentration 0.01 mg/mL. After reaching equilibrium, the suspension was centrifuged, and solution was analyzed for the concentration of Rh.B left using a spectrophotometer at λ max = 554 nm. The removed quantity (q eq in mg/L) of the dye selleckchem by G/M-CdS could be calculated as (1) where C 0 (mg/L) represents the initial dye concentration, C eq (mg/L) is the equilibrium concentration of the dye remaining in the solution every test, V (L) is the volume of the aqueous solution, and m (g) is the weight of the G/M-CdS composite. Photocatalytic experiments

were conducted to photocatalytically degrade Rh.B in water under visible light irradiation. A domestic visible light lamp (11 W) was used as a light source and set about 10 cm from the reactor. ARRY-438162 experiments were carried out at ambient

temperature. The reaction suspension was prepared in the same fashion as in the adsorption experiments. Before irradiation, the solutions were stirred in the dark in order to reach the adsorption-desorption equilibrium. At different irradiation SB202190 time intervals, analytical samples were taken from the reaction suspension and centrifuged to remove the photocatalyst particles. The concentrations of the remnant Rh.B were monitored by checking the absorbance of solutions. Results and discussion As shown in Figure  1, XRD measurements were performed to obtain crystalline structural information for the as-synthesized GO, CdS MPs, and G/M-CdS. The GO presents a very sharp diffraction peak at 10.3°, whereas the weak and broad peak between 20° to 30° suggests residual unoxidized graphite. The characteristic

peaks at 24.86°, 26.48°, 28.32°, 36.72°, 43.77°, 47.98°, and 52.0° correspond to (100), (002), (101), (102), (110), (103), and (200) planes of hexagonal-phase CdS crystals. The XRD results clearly suggest that the addition of graphene oxide did not influence the crystal structure of hexagonal phase CdS. The crystallinity of the G/M-CdS sample is very close to that of CdS, indicating that the GO supplies a platform in which the CdS particles can nucleate and grow. In addition, the 2θ degree of the peaks in pure G/M-CdS shifted a little to smaller coordinate numbers compared with those in pure CdS, which implies that the interplanar distance of graphene-coated CdS L-gulonolactone oxidase is larger than that of pure CdS. A possible reason to this might be that graphene nanosheets afforded electrons to Cd atom, which reduced the electrostatic attraction between Cd atom and S atom, and weakened the binding energy [34]. This phenomenon suggests that the G/M-CdS hybrid is formed. This result also agrees with previous works, in which GO is used as a support material to prepare graphene-based nanomaterials [35, 36]. Figure 1 XRD patterns of the as-prepared CdS MPs, G/M-CdS, and GO samples. The morphologies of the as-prepared G/M-CdS composites were characterized by SEM and TEM.