One‐Step Construction of Novel PbBiO₂Br/ZnO Heterojunction Composites with Enhanced Photocatalytic Activity

Abstract

PbBiO2Br/ZnO heterojunction composites are synthesized using a one‐step method. The as‐synthesized samples are characterized by X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy (XPS), field‐emission scanning electron microscopy (FE‐SEM), energy‐disperse X‐ray spectroscopy (EDX), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), ultraviolet‐visible diffuse reflectance spectroscopy (UV‐vis DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of the PbBiO2Br/ZnO heterojunction composites is assessed by measuring the removal of methyl orange (MO) from wastewater under simulated sunlight irradiation. The results demonstrate that the PbBiO2Br/ZnO heterojunction composites are composed of ZnO nanorods and PbBiO2Br cubic nanosheets. The PbBiO2Br/ZnO heterojunction composites exhibit enhanced photocatalytic performances for the degradation of MO under irradiation by simulated sunlight. Among the composites, the 10% PbBiO2Br/ZnO composite exhibits optimal activity, and the removal percentage of the dye reaches 92.1% after 60 min of reaction. This is mainly attributed to the efficient separation of photo‐generated e−–h+ pairs and the formation of heterojunctions. According to the active species trapping experiments, photo‐generated h+ is confirmed to be the main active species, whereas ·boldObold2bold− and ·OH play a secondary role in the reaction process. Additionally, the recycling experiments suggest that the PbBiO2Br/ZnO composites have good stability in the reaction process.

Fabrication and photocatalytic performance of Bi 24 O 31 Br 10 nanosphere by a polyacrylamide gel method

“…Under visible light irradiation, electrons are excited from the VB of Bi 24 O 31 Br 10 to the CB, meanwhile generating h + in the VB. The photoelectrons on the CB of Bi 24 O 31 Br 10 react with O 2 to form , and then reacts with H + to generated •OH due to the sufficiently negative CB potential compared to the standard redox potential of E θ (O 2 /) (−0.33 eV versus normal hydrogen electrode (NHE)) [18, 19]. Finally, the •OH radicals remove MO.…”

“…Introduction: Semiconductor photocatalysis has been regarded as an application prospect in the degradation of organic pollutants [1]. TiO 2 and ZnO are the best photocatalytic materials due to their non-toxic nature, chemical stability, and low cost [2]. Unfortunately, TiO 2 and ZnO can only respond ultraviolet (UV) light because of their wide bandgaps [3].…”

Construction of Cu7S4@CuCo2O4 Yolk–Shell Microspheres Composite and Elucidation of Its Enhanced Photocatalytic Activity, Mechanism, and Pathway for Carbamazepine Degradation

“…To verify the efficient interfacial charge transfer via a direct Z-scheme pathway in the CS/ CCO composites, we analyzed the density functional theory (DFT) for the composites (Section S1, Supporting Information). [51,52] The blue and yellow isosurfaces of the charge density distribution represent the electron-abundant and electron-scarce regions, respectively. Hence, the CS/CCO system revealed electron-scarce regions around CCO and electron-abundant regions of CS, indicating that the electron migration was from the CCO to CS via a Z-scheme rather than a Type-II heterojunction scheme pathway.…”

Recent Progress and Perspectives of S-Scheme Heterojunction Photocatalysts for Photocatalytic CO2 Reduction

“…Since 1979, when Inoue reported the ability of semiconductor photocatalysts to reduce CO 2 in water to organic compounds . Researchers have developed a number of semiconductor photocatalysts for photocatalysis, which can be categorized into the six categories below (1) metal oxides, such as TiO 2 , , ZnO; , (2) metal sulfides, such as CdS, ZnS, ZnIn 2 S 4 ; (3) metal nitrides and phosphides, such as GaN, Ni 2 P; (4) layered metal hydroxides, such as NiAl-LDH, MgAl-LDH; (5) metal–organic framework materials (MOFs); and (6) nonmetallic semiconductors, such as g-C 3 N 4 . , …”