Synthesis of Ag/AgBr/Bi₄O₅Br₂ Plasmonic Heterojunction Photocatalysts: Elevated Visible‐light Photocatalytic Performance and Z‐scheme Mechanism

Abstract

The novel photocatalysts of Ag/AgBr/Bi 4 O 5 Br 2 layered microspheres (AAB-LMs) were firstly constructed via the in-situ deposition and visible-light photoreduction approach. Their compositions, structures, morphologies and optical properties were characterized by various techniques. The photocatalytic efficiencies of AAB-LMs-10 were 28 and 3.4 times higher than those of Bi 4 O 5 Br 2 -LMs towards degrading acid orange II and aniline, respectively. The superior photocatalytic behavior of AAB-LMs benefited from efficient separation and transfer of photo-generated charges, which was mainly credited to the surface plasmon resonance effect of Ag nanoparticles and the synthetic interaction among Ag, AgBr and Bi 4 O 5 Br 2 . O 2 À and h + were characterized as the predominant photoactive species in this AAB-LMs-photocatalysis system. Moreover, due to the presence of radical species Br 0 , which was verified by the detection of bromoaniline and dibromoaniline during the photocatalytic degradation process of aniline, Z-scheme mechanism rather than the conventional heterojunction mode was more suitable to explain the enhanced photocatalytic performance of AAB-LMs.

Microwave-assisted synthesis of a Z-scheme heterojunction Ag/AgBr@BiOBr/Bi2O3 photocatalyst for efficient organic pollutant degradation under visible light

“…4d). 18,31 The O 1s peak could be deconvoluted into two peaks related to oxygen in the nanocomposite (Fig. 4e).…”

“…17 A Z-scheme Ag/AgBr/Bi 4 O 5 Br 2 photocatalyst was also synthesized using a hydrothermal method (160 °C for 12 h) to decompose acid orange II, 4- tert -butylphenol, and aniline. 18 Several studies have been conducted to improve the photocatalytic activity of catalysts. Nevertheless, these fabrication routes posed obstacles for practical applications related to their high-energy consumption, lengthy production time, complicated synthesis procedures, and environmental problems from toxic solvents.…”

Recent trends in Bi-based nanomaterials: challenges, fabrication, enhancement techniques, and environmental applications

“…Many persistent organic contaminants can be degraded at room temperature through the oxidizing power of VB holes in bismuth oxyhalides [26]. BiOCl, BOI, BiOBr, and composites made from them have been widely reported due to their excellent photocatalytic properties [27][28][29]. However, the photocatalytic effectiveness of those semiconductors is inadequate for practical environmental and energy conservation applications because of substantial electron-hole recombination and a low capacity for the absorption of visible light.…”

PVP‐assisted synthesis of P‐Bi4O5Br2/AgI heterojunction with enhanced photocatalytic activity for degradation of rhodamine B

“…[6][7][8] Whatʼs more, Bi 4 O 5 Br 2 has a relatively narrow bandgap (2.36 eV), which could get a higher visible light absorption capacity. 9 Meanwhile, its photogenerated carriers are easy to recombine, reducing the photocatalytic performance. 10,11 Constructing heterojunctions could effectively constrain the recombination of carriers, boosting the photocatalytic performance of Bi 4 O 5 Br 2 by combining with another semiconductor (such as BiOBr, AgBr, g-C 3 N 4 , etc.).…”