Preparation of Visible Light Active Ag‐ and N‐Doped KVMoO₆: Photodegradation of Methylene Blue

Abstract

Brannerite-type layered vanadomolybdate, KVMoO 6 , was synthesized by sol-gel method using ethylene glycol as gelating agent. Its silver-and nitrogen-doped analogues were prepared by ion exchange and solid state methods, respectively. All compounds were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive spectroscopy (EDS), Fourier transform IR spectroscopy (FT-IR), and UV-vis diffuse reflectance spectra. The bandgap energy of all compounds was obtained from their diffuse reflectance spectra. Bandgap was reduced considerably upon silver and nitrogen doping in KVMoO 6 . The photocatalytic activity of parent and doped samples was studied by degradation of methylene blue. The nitrogen-doped KVMoO 6 shows higher photocatalytic activity against the degradation of methylene blue. The stability and reusability of the nitrogen-doped KVMoO 6 were investigated. N-doped KVMoO 6 is a potential catalytic material for cleaning wastewater.

Enhancement of Photocatalytic Activity of Sodium Bismuth Titanate by Doping with Copper, Silver, and Tin Ions

“…The presence of Ag in the ANBT sample can be distinguished by two peaks centered at 367.2 eV and 373.4 eV, which are assigned to Ag 3d 3/2 and Ag 3d 5/2 , respectively (Figure e). These results confirm the presence of Ag + ion on the surface of ANBT . The Cu 2p spectrum displays Cu 2p 3/2 and Cu 2p 1/2 peaks centered at 934.4 and 954.6 eV, respectively, accompanied by two satellite signals at 943.6 and 963.2 eV, which corroborates the presence of Cu 2+ on the surface of CNBT (Figure f) , …”

Effect of Ag+, Cu2+ and Sn2+ Doping on Structural, Optical and Photocatalytic Properties of KGe0.5Te1.5O6 with Defect Pyrochlore Structure

“…The Ag 3d XPS spectrum of the Ag-KGTO sample exhibited the 3d 5/2 and 3d 3/2 peaks at 367.3 and 373.5 eV (Figure 4e), which are characteristics of Ag + ion. [48] As shown in Figure 4f, the Cu 2p XPS spectrum of the Cu-KGTO catalyst comprised 2p 3/2 and 2p 1/2 sublevels (at 934.4 and 954.7 eV, respectively) along with their corresponding satellites, which confirms the 2 + oxidation state of Cu. [49] The XPS spectrum of Sn 3d of Sn-KGTO is shown in Figure 4g.…”

“…Thus, it can be concluded that the Sn‐KGTO sample may exhibit higher photocatalytic activity originating from its highest surface adsorbed oxygen species. The Ag 3d XPS spectrum of the Ag‐KGTO sample exhibited the 3d 5/2 and 3d 3/2 peaks at 367.3 and 373.5 eV (Figure 4e), which are characteristics of Ag + ion [48] . As shown in Figure 4f, the Cu 2p XPS spectrum of the Cu‐KGTO catalyst comprised 2p 3/2 and 2p 1/2 sublevels (at 934.4 and 954.7 eV, respectively) along with their corresponding satellites, which confirms the 2+ oxidation state of Cu [49] .…”