Novel AgBr/Ag₃PO₄ Decorated Ceria Nanoflake Composites for Enhanced Photocatalytic Activity toward Dyes and Bacteria under Visible Light

Abstract

The aim of this study was to develop heterogeneous visible light active photocatalysts using AgBr and Ag3PO4 using CeO2 nanoflakes as an efficient substrate. Ascorbic acid was employed as a fuel to synthesize fine ceria nanoflakes by a facile solution combustion process. AgBr and Ag3PO4 were decorated on ceria to prepare AgBr/Ag3PO4/ceria nanocomposites. The structure of the composite was determined by X-ray diffraction analysis. Novel flake-like morphology was revealed using electron microscopy techniques. The nanocomposites exhibit excellent photocatalytic activity under visible light compared to pristine ceria nanoparticles. The nanocomposite catalyst particles degraded both anionic and cationic dyes. It also exhibited efficient antimicrobial activity under visible light.AgBr/Ag3PO4/ceria nanocomposite was characterized using X-ray diffraction analysis, diffuse reflectance spectroscopy, electron microscopy, BET surface area analysis, X-ray photoelectron spectroscopy and the reasons for enhanced photocatalytic activity were elucidated. The presence of silver based semiconductors on ceria has shown to decrease charge recombination through photoluminescence analysis that attributed for enhanced photocatalytic activity. The AgBr/Ag3PO4/ceria nanocomposite has shown a stable performance after many repeated cycles.

Cerium and Its Oxidant-Based Nanomaterials for Antibacterial Applications: A State-of-the-Art Review

“…Various semiconductors like TiO 2 and CeO 2 could be coupled with compounds derived from silver to enhance charge separation and induce photocatalytic activity under visible light. Eswar et al (2015) synthesized CeO 2 by two different methods. The low-band-gap CeO 2 synthesized using the polyethylene glycol (PEG)-assisted sonochemical method was named P-CeO 2 .…”

“…All the composites had at least 1 log colony-forming unit (CFU) reduction in the dark, and after eliminating the photolysis factor, all the composites had at least 3 log CFU extra reduction under visible light. Among them, the CeO 2 /AgBr/Ag 3 PO 4 composite showed a superior bactericidal efficiency compared to other composites under visible light due to ROS and elution of Ag + into the reaction system (Eswar et al, 2015).…”

Palladium‐Supported Nanoceria: A Highly Efficient Catalyst for Solvent‐Free Selective Oxidation of Ethylbenzene to Acetophenone

“…Figure shows the XRD patterns of the as‐synthesized CeO 2 and Pd/CeO 2 . The reflexes of CeO 2 are indexed to cubic fluorite crystal structure with space group Fm‐3 m (JCPDS 081–0792) . The characteristics reflexes at 28.56°, 33.16°, 47.52°, 56.34°, 59.07°, 69.58°, 76.81°, 78.87° are assigned to the (111), (200), (220), (311), (222), (400), (331), (420) crystal facets of CeO 2 respectively.…”

Study on the Visible-Light Photocatalytic Performance and Degradation Mechanism of Diclofenac Sodium under the System of Hetero-Structural CuBi2O4/Ag3PO4 with H2O2

“…According to the Kubelka-Munk function [ 27 ] and the plot of ( αhv ) 2 vs. hv (shown in Figure 3 b), the band gaps (Eg) of CuBi 2 O 4 , Ag 3 PO 4 -SC, and Ag 3 PO 4 -SS can be estimated as 1.72 eV, 2.38 eV, and 2.42 eV, respectively. Besides, the band-edge potentials of the conduction band (E CB ) and valence band (E VB ) can be designated as [ 28 ]: and where X is the geometric mean of the electronegativity of the constituent atoms (5.96 eV for Ag 3 PO 4 , and 4.59 eV for CuBi 2 O 4 [ 28 , 29 ]), and E c is the energy of the free electrons on the hydrogen scale (approximately 4.5 eV) [ 28 ]. Therefore, the E VB and E CB of CuBi 2 O 4 can be estimated to be 0.95 and −0.77 eV/NHE, the E VB and E CB of Ag 3 PO 4 -SC can be estimated to be 2.65 and 0.27 eV/NHE, while the E VB and E CB of Ag 3 PO 4 -SS are estimated to be 2.67 and 0.25 eV/NHE, respectively.…”