Microwave-assisted synthesis of 3D Bi2MoO6 microspheres with oxygen vacancies for enhanced visible-light photocatalytic activity

Huang, Chengjuan; Ma, Shuaishuai; Zong, Yuqing; Gu, Jiandong; Xue, Jinjuan; Wang, Mingxin

doi:10.1039/d0pp00247j

Cited by 25 publications

(16 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The stacking mode between the sheets is changed; thus, the three-dimensional space of 5-CBMOS is significantly stronger than that of BMOS. It assists in exposing more catalytic active sites, which is beneficial for the adsorption and activation of O 2 and reactants. , Figure e is the TEM image of 5-CBMOS, showing the ultrathin sheet structure, which is consistent with the SEM results. The crystal structure of 5-CBMOS is further magnified, and the lattice fringes with a spacing of 0.274 nm correspond to the {002} crystal plane of the orthorhombic phase Bi 2 MoO 6 (Figure f). , Energy-dispersive X-ray spectroscopy (TEM–EDX) results of the prepared samples indicate that Bi, Ce, Mo, and O elements contained in 5-CBMOS are uniformly distributed in the matrix material (Figure g), which further confirm the successful synthesis of the Ce-doped Bi 2 MoO 6 composite.…”

Section: Resultssupporting

confidence: 80%

“…By comparing the SEM images of BMOS and 5-CBMOS, Ce doping has few effects on the thickness, but it can make the sheet size of Bi 2 MoO 6 increase slightly.The stacking mode between the sheets is changed; thus, the threedimensional space of 5-CBMOS is significantly stronger than that of BMOS. It assists in exposing more catalytic active sites, which is beneficial for the adsorption and activation of O 2 and reactants 42,43. Figure1eis the TEM image of 5-CBMOS, showing the ultrathin sheet structure, which is consistent with the SEM results.…”

supporting

confidence: 82%

See 1 more Smart Citation

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi₂MoO₆ Nanosheets for Toluene Selective Oxidation

Zeng

Wang

Sheng

et al. 2023

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

The generation of reactive oxygen species (ROS) from O 2 is a critical step to boost the performance of photocatalytic toluene oxidation. However, the production of ROS is greatly limited by the serious recombination of charge carriers and the lack of O 2 adsorption sites. In this work, Ce-doped Bi 2 MoO 6 ultrathin nanosheets with rich oxygen defects are prepared by a one-step hydrothermal method. The ultrathin structure promotes the longitudinal transport of carriers to the surface. The introduction of Ce ions generates both Ce 3+ /Ce 4+ redox ion pairs and oxygen defects in Bi 2 MoO 6 , where the former promotes the transfer of photogenerated electrons and the latter enhances the adsorption of O 2 , thereby producing more superoxide radicals (•O 2 − ). Attributed to these advantages, Ce-doped Bi 2 MoO 6 ultrathin nanosheets exhibit excellent photocatalytic activity for toluene selective oxidation. The toluene conversion rate is 4422 μmol•g −1 •h −1 . The selectivity values of benzaldehyde and benzyl alcohol are 84.7 and 15.3%, respectively. In addition, the mechanism of photocatalytic selective oxidation of toluene is further explored through a series of experiments.

show abstract

Section: Resultssupporting

confidence: 80%

supporting

confidence: 82%

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi₂MoO₆ Nanosheets for Toluene Selective Oxidation

Zeng

Wang

Sheng

et al. 2023

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…Notably, compared to various conventional processes and advanced oxidation processes, “heterogeneous photocatalysis” , is considered to be a more viable option for degradation of antibiotics without the use of any exogenous supply of H 2 O 2 . This is a “green approach”, where semiconductor-type photocatalysts upon absorbing light of energy greater than its band gap can in situ generate a plethora of reactive oxygen species (ROS), for example, hydroxyl radicals, superoxide radicals, singlet oxygen, and H 2 O 2 . , It was noted in the literature that the nanocomposites (NCs) made of other metal oxide systems with carbonaceous materials, for example, N-doped carbon-coated mulberry-like cobalt manganese oxide (H-CoMnO x @NC) as a photo-Fenton-like catalyst, has shown excellent results for removal of seven different pharmaceutically active compounds . However, TiO 2 and ZnO nanoparticles (NPs) are most widely used photocatalysts owing to excellent photocatalytic performance, high chemical stability, and non-toxic nature. − They are both wide band gap materials, which necessitate the use of UV light for photoexcitation.…”

Section: Introductionmentioning

confidence: 99%

“…This is a "green approach", where semiconductor-type photocatalysts upon absorbing light of energy greater than its band gap can in situ generate a plethora of reactive oxygen species (ROS), for example, hydroxyl radicals, superoxide radicals, singlet oxygen, and H 2 O 2 . 9,10 It was noted in the literature that the nanocomposites (NCs) made of other metal oxide systems with carbonaceous materials, for example, N-doped carbon-coated mulberry-like cobalt manganese oxide (H-CoMnO x @NC) as a photo-Fenton-like catalyst, has shown excellent results for removal of seven different pharmaceutically active compounds. 11 and non-toxic nature.…”

Section: Introductionmentioning

confidence: 99%

Sunlight-Driven Photocatalytic Degradation of Ciprofloxacin by Carbon Dots Embedded in ZnO Nanostructures

Mukherjee

Cilamkoti

Dutta

2021

ACS Appl. Nano Mater.

102

View full text Add to dashboard Cite

Surface modification of ZnO nanoparticles (NPs) is considered as a key for enhanced sustained generation of reactive oxygen species (ROS) in the reaction medium for improving the photocatalytic degradation phenomenon. Here, we present a simple chemical method of synthesizing carbon dots (CDs) embedded on the surface of ZnO NPs denoted as ZnO/CD nanocomposites (NCs) as a photocatalyst for efficient sunlight-driven degradation of ciprofloxacin (CIP). The X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies confirmed the formation of needle-shaped clusters of ZnO/CD NCs. The band gaps of ZnO/CD NCs and pristine ZnO are determined from Tauc's plot. Under optimized conditions, the batch of CIP at pH 6.3 ± 0.1 treated with 0.6 g L −1 of ZnO/CD NCs revealed 98% photocatalytic degradation of CIP in 110 min by harnessing longer UV and the visible components of sunlight. The rate of photocatalytic degradation was 0.30 min −1 , which was 3 times higher than that of the pristine ZnO NPs. The enhanced rate of degradation by ZnO/CD NCs is attributed to the improved mobility of charge carriers and the generation of enhanced ROS. This is confirmed by the scavenging studies of hydroxyl radicals and superoxide radicals. The higher ROS generation is attributed to the inhibition of charge carrier recombination facilitated by the CDs embedded on the surface of ZnO NPs. The applicability of ZnO/CD NCs as a photocatalyst is demonstrated from five cycles of repeatability studies. After five cycles of operation, the structure and surface morphology of the used ZnO/CD NCs were stable, confirmed by XRD, TEM, and Fourier transform infrared studies. It is concluded that ZnO/CD NCs are efficient sunlight-driven photocatalysts for improved photocatalytic degradation of CIP, a model emerging contaminant.

show abstract

“…Bi vacancy and Bi interstitial contained in Bi 2 MoO 6 were synthesized by Zhang et al exhibiting higher photoexcitation. Significantly, the single V O defect in Bi 2 MoO 6 is more importantly studied due to its relatively lower formational energy. , Huang et al synthesized different amounts of V O in Bi 2 MoO 6 with the higher tetracycline degradation rate of Bi 2 MoO 6 . Bai et al calcined Bi 2 MoO 6 at 450 °C and found that it exhibited much higher photocatalytic performance owing to the existence of V O .…”

Section: Introductionmentioning

confidence: 99%

Temperature, Doping, and Chemical Potential Tuning Intrinsic Defects Concentration in Bi₂MoO₆: GGA + U Method

2023

View full text Add to dashboard Cite

Using the GGA + U method, the formation energy and concentration of intrinsic defects in Bi2MoO6 are explored under different chemical conditions, with/without doping, from 120 to 900 K. We find that the intrinsic defect and carrier concentration can be deduced from the small range of calculated Fermi levels in the diagram of formation energy vs Fermi level under different conditions. Once the doping conditions or/and temperature are determined, the corresponding E F is only limited to a special region in the diagram of formation energy vs Fermi level, from which the magnitude relationship of defects concentration can be directly derived from their formation energy. The lower the defect formation energy is, the higher the defect concentration is. With E F moving under different doping conditions, the intrinsic defect concentration changes accordingly. At the same time, the highest electron concentration at the relative O-poor (point HU ) with only intrinsic defects confirms its intrinsic n-type behavior. Moreover, upon A–/D+ doping, E F moves closer to VBM/CBM for the increasing concentration of holes/electrons. The electron concentration can also be further improved after D+ doping, indicating that D+ doping under O-poor chemical growth conditions is positive to improve its photogenerated carriers. This provides us with a method to adjust the intrinsic defect concentration and deepens our knowledge about comprehension and application of the diagram of formation energy vs Fermi level.

show abstract

Microwave-assisted synthesis of 3D Bi2MoO6 microspheres with oxygen vacancies for enhanced visible-light photocatalytic activity

Abstract: Oxygen vacancies (OVs) defect in metal oxide-based photocatalysts play crucial role in improving their charge carrier separation efficiencies to enhance their photocatalytic performances. In this work, OVs were introduced in...

Cited by 25 publications

References 46 publications

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi₂MoO₆ Nanosheets for Toluene Selective Oxidation

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi₂MoO₆ Nanosheets for Toluene Selective Oxidation

Sunlight-Driven Photocatalytic Degradation of Ciprofloxacin by Carbon Dots Embedded in ZnO Nanostructures

Temperature, Doping, and Chemical Potential Tuning Intrinsic Defects Concentration in Bi₂MoO₆: GGA + U Method

Contact Info

Product

Resources

About

Microwave-assisted synthesis of 3D Bi2MoO6 microspheres with oxygen vacancies for enhanced visible-light photocatalytic activity

Abstract: Oxygen vacancies (OVs) defect in metal oxide-based photocatalysts play crucial role in improving their charge carrier separation efficiencies to enhance their photocatalytic performances. In this work, OVs were introduced in...

Cited by 25 publications

References 46 publications

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi2MoO6 Nanosheets for Toluene Selective Oxidation

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi2MoO6 Nanosheets for Toluene Selective Oxidation

Sunlight-Driven Photocatalytic Degradation of Ciprofloxacin by Carbon Dots Embedded in ZnO Nanostructures

Temperature, Doping, and Chemical Potential Tuning Intrinsic Defects Concentration in Bi2MoO6: GGA + U Method

Contact Info

Product

Resources

About

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi₂MoO₆ Nanosheets for Toluene Selective Oxidation

Ce Doping Boosts the Photocatalytic Activity of Ultrathin Bi₂MoO₆ Nanosheets for Toluene Selective Oxidation

Temperature, Doping, and Chemical Potential Tuning Intrinsic Defects Concentration in Bi₂MoO₆: GGA + U Method