Ag-modified g-C₃N₄ with enhanced activity for the photocatalytic reduction of hexavalent chromium in the presence of EDTA under ultraviolet irradiation

One-Step Fabrication of the ZnO/g-C3N4 Composite for Visible Light-Responsive Photocatalytic Degradation of Bisphenol E in Aqueous Solution

“…Furthermore, the high-resolution O 1s XPS spectra of g-C 3 N 4 showed one peak at 532.2 eV, which is assigned to the surface −OH groups on the g-C 3 N 4 or in the adsorbed H 2 O. 54 In contrast, the high-resolution O 1s XPS spectra of ZnO/g-C 3 N 4 illustrated two peaks at 530.9 and 531.9 eV for O 2 2– in the ZnO wurtzite structure and surface −OH groups adsorbed on the composite, respectively ( Figure 3 d). 50 In the case of the high-resolution Zn 2p XPS spectrum of the ZnO/g-C 3 N 4 composite, as shown in Figure 3 e, the binding energy values of Zn 2p 3/2 and Zn 2p 1/2 were located at 1021.8 and 1044.9 eV, representing the Zn 2+ oxidation state of the ZnO material, respectively.…”

“…The high-resolution C 1s XPS spectrum of g-C 3 N 4 can be deconvoluted into four components located at 287.6, 285.1, 284, and 288.4 eV, which are related to the NC–N groups of the s-triazine ring, sp 3 C–N bond, sp 2 CC bond, and C–O groups induced by unavoidable oxidation of the sample, respectively (Figure b). As shown in Figure c, the high-resolution XPS N 1s spectrum of g-C 3 N 4 was fitted by the three peaks of 403.9, 399.7, and 398.1 eV, which can be ascribed to the sp 2 N (CN–C) involved in the triazine ring, tertiary nitrogen atom (NC 3 ), or secondary nitrogen atom (HNC 2 ), and the charging effects or positive charge localized in the heterocycles, respectively . Moreover, the position and relative intensity of the peaks in the high-resolution C 1s and N 1s XPS spectra of the ZnO/g-C 3 N 4 composite were changed, , as shown in Figure b,c.…”

“…Moreover, the position and relative intensity of the peaks in the high-resolution C 1s and N 1s XPS spectra of the ZnO/g-C 3 N 4 composite were changed, , as shown in Figure b,c. Furthermore, the high-resolution O 1s XPS spectra of g-C 3 N 4 showed one peak at 532.2 eV, which is assigned to the surface −OH groups on the g-C 3 N 4 or in the adsorbed H 2 O . In contrast, the high-resolution O 1s XPS spectra of ZnO/g-C 3 N 4 illustrated two peaks at 530.9 and 531.9 eV for O 2 2– in the ZnO wurtzite structure and surface −OH groups adsorbed on the composite, respectively (Figure d) .…”

“…Figure a shows the Kubelka-Munk function of the UV–vis DRS of the prepared ZnO, g-C 3 N 4 , and the ZnO/g-C 3 N 4 composite after the degradation reaction of BPE. It was observed that the prepared ZnO and g-C 3 N 4 had the absorption edge at about 390 and 430 nm, respectively. Moreover, the absorption edge of the prepared ZnO/g-C 3 N 4 composite was significantly red-shifted to a higher wavelength compared to both pure ZnO and g-C 3 N 4 .…”

“…As shown in Figure 3c, the high-resolution XPS N 1s spectrum of g-C 3 N 4 was fitted by the three peaks of 403.9, 399.7, and 398.1 eV, which can be ascribed to the sp 2 N (C�N−C) involved in the triazine ring, tertiary nitrogen atom (NC 3 ), or secondary nitrogen atom (HNC 2 ), and the charging effects or positive charge localized in the heterocycles, respectively. 54 Moreover, the position and relative intensity of the peaks in the high-resolution C 1s and N 1s XPS spectra of the ZnO/g-C 3 N 4 composite were changed, 51,53 as shown in Figure 3b,c. Furthermore, the high-resolution O 1s XPS spectra of g-C 3 N 4 showed one peak at 532.2 eV, which is assigned to the surface −OH groups on the g-C 3 N 4 or in the adsorbed H 2 O.…”