25 M Na2SO3 and 0.35 M Na2S were added into the reaction cell. Then, these photocatalysts were directly placed into the electrolyte solution. The whole system was vacuumized with a vacuum pump before reaction to remove the dissolved air. The temperature for all photocatalytic reactions was kept at about 20°C. Results and discussions The surface morphologies of the obtained Cd1−x Zn x S are shown in Figure 1. Figure 1a is the scanning electron microscopy (SEM) image of CdS; it presents porous flower-like 3D structure clearly, shorter nanowires appear at the periphery. As the value of

x increases, nanosheet emerges gradually, PLX3397 research buy that is, the secondary structure builds up slowly. Figure 2 shows the XRD patterns of the as-prepared photocatalysts. CdS exhibits a Greenockite structure, while ZnS presents a Wurtzite polycrystalline structure, respectively. The diffraction peaks of the photocatalysts shift to a higher angle side as the value of x increases. The successive shift of the

XRD patterns means that the crystals obtained are Cd1−x Zn x S solid solution, not a simple mixture of ZnS and CdS [26]. Figure 1 Typical SEM images of the obtained Cd 1− x Zn x S photocatalysts. (a) Cd0.98S, (b) Cd0.9Zn0.1S, (c) Cd0.72Zn0.26S, and (d) Cd0.24Zn0.75S. Figure 2 XRD patterns of the as-prepared Cd 1− x Zn x S photocatalysts with different x values. (curve a) Cd0.98S, (curve b) Cd0.9Zn0.1S, (curve c) Cd0.72Zn0.26S, (curve d) Cd0.24Zn0.75S, and (curve e) Zn0.96S. The surface information is collected by XPS of the sample CFTRinh-172 supplier Cd0.72Zn0.26S (Figure 3). The survey scan spectrum (Figure 3a) indicates the existence of Cd, Zn, and S in the Cd0.72Zn0.26S sample. The two sharp peaks (Figure 3b) located at 404.3 and 411.2 eV are corresponding to the Cd 3d5/2 and Cd 3d3/2 level, respectively. The peaks of 1,020.8 and 1,043.7 eV can be assigned to the Zn 2p3/2 and 2p1/2 levels, find more respectively (Figure 3c). The single S 2p peak at 161.1 eV (Figure 3d) demonstrates that sulfur exists as a sulfur ion. Figure 3 Representative XPS spectra of typical sample Cd 0.72

Zn 0.26 S. (a) survey spectrum, (b) Cd 3d XPS spectrum, (c) Zn 2p XPS spectrum, and (d) S 2p XPS spectrum. Raman scattering is a nondestructive technique for structural study of the material Molecular motor and a powerful probe to obtain the vibrational states of a solid. It is an inelastic process in which incoming photons exchange energy with the crystal vibrational mode. Figure 4 reveals the Raman spectrum of the as-obtained Cd0.72Zn0.26S sample. Bulk CdS has two characteristics of longitudinal-optical (LO) phonon peaks: (1) 1-LO (first harmonic (at 300/cm)) and (2) 2-LO (second harmonic (at 600/cm)) vibrations [27]. The two phonon peaks are also observed in the as-obtained Cd0.72Zn0.26S; they are located at 306.5 and 608.1/cm, respectively, and shift toward the higher energy side compared with that of the pure CdS.