Ag/AgCl nanoparticles embedded in porous TiO₂: defect formation triggered by light irradiation

Abstract

Ag/AgCl nanoparticles embedded in defective porous titanium dioxide (Ag/AgCl-pTiO2) have been successfully prepared via the solvent-free sol-gel process, and their role as visible-light-responsive photocatalysts was investigated. The crystal phase, morphology,...

Preparation of CS-LS/AgNPs Composites and Photocatalytic Degradation of Dyes

“…As shown in Figure 4 b, in the XRD pattern of CS-LS/AgNPs, apart from the original characteristic peaks of CS and LS, four characteristic peaks at 2θ = 37.53°, 46.35°, 64.94°, and 77.69° are attributed to the (111), (200), (220), and (311) planes of face-centered cubic silver, respectively. The peak corresponding to the (111) plane is stronger than those in other planes, indicating the dominance of the (111) plane [ 30 , 31 ]. In order to further determine the changes in element distribution and electron density, XPS measurements were performed on the prepared CS-LS/AgNPs.…”

“…First, in order to explore the active groups under CS-LS/AgNPs photocatalytic conditions, IPA, EDTA, AgNO 3 , and BQ were used as scavengers of ·OH, h + , ·O 2 − , and e − under ultraviolet irradiation ( Figure 8 ). Based on the results of the capture experiment, a possible reaction process is proposed [ 30 , 33 ], as follows: AgNPs + hv + UV → e − + h + O 2 + e − → ·O 2 − h + + OH − → ·OH ·O 2 − (h + /·OH) + RhB → H 2 O + CO 2 + other degradation products …”

“…First, in order to explore the active grou LS/AgNPs photocatalytic conditions, IPA, EDTA, AgNO3, and BQ were us gers of •OH, h + , •O2 -, and eunder ultraviolet irradiation (Figure 8). Based on the capture experiment, a possible reaction process is proposed [30,33], as f AgNPs + hv + UV → e -+ h + O2 + e -→ •O2h + + OH -→ •OH •O2 -(h + /•OH) + RhB → H2O + CO2 + other degradation produ From the above results, the photocatalytic mechanism of CS-LS/AgNP (Figure 9). The photocatalytic degradation mechanism mainly consists of t the adsorption of pollutants/dyes on the surface of the composite, (b) the light by the composite, and (c) the generation of e − -h + .…”

Enhanced Decomposition of H2O2 Using Metallic Silver Nanoparticles under UV/Visible Light for the Removal of p-Nitrophenol from Water

“…As a matter of fact, when the Ag NPs' shape evolved from spherical to hexagonal/rod-like, it produced more defects in the structure [43]. It is known that photocatalysts with defects, up to a certain amount, have a better e − -h + charge separation [56,57]. The better activity of Ag400 can be due to this phenomenon, with this sample being an intermediate between the Ag200 (spherical shapes with low defects) and Ag800 (hexagonal/rod-like shapes with many defects) structures.…”