APPLIED CATALYSIS B-ENVIRONMENTAL
·
2017
·
IF 9.446
Wenlong Zhen,Xiaofeng Ning,Baojun Yang,Yuqi Wu,Zhen Li,Gongxuan Lu
CdS photocorrosion seriously impeded its application in photocatalysis , especially for water splitting. Here we report new strategies to improve CdS photocorrosion resistance properties significantly by coating Ni 2 P shell and assembling an artificial gill to remove newly formed O 2 from water. Ni 2 P@CdS catalyst can achieve the over-all water splitting under visible light irradiation without addition of any sacrifice reagent and noble metal loading. Compared with CdS itself, the 10Ni 2 P@CdS photocatalyst exhibits excellent photocatalytic activity for hydrogen evolution (251.4 μmol of H 2 in 180 min) with a high AQE (3.89% at 430 nm). This catalyst also presents high photocurrent, low overpotential (−0.32 V vs SCE), and long fluorescence lifetime (16.27 ns) of excited charges. Cd 2+ ions concentration measured by ICP and long term stability results verified the anti-photocorrosion role of Ni 2 P shell on CdS during water splitting reaction. The activity and stability of 10Ni 2 P@CdS is even superior to typical 1Pt@CdS catalyst. Our results confirm CdS can be an active catalyst for photocatalytic hydrogen generation from water under visible irradiation if its stability is enhanced by protection of anti-photocorrosion over-coating shell and removing the nascent formed oxygen from water.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2018
·
IF 11.698
Ning Shao,Zhiang Hou,Hanxu Zhu,Jinnan Wang,Corvini Philippe François-Xavier
To improve the visible-light photocatalytic activity and anti-photocorrosion of Ag 3 PO 4 , novel 3D core-shell CQDs/Ag 3 PO 4 @benzoxazine tetrapods with more exposure of {110} facets of Ag 3 PO 4 has been successfully synthesized for the first time by electrochemical oxidation, chemical precipitation and molecular self-assembly reaction. In CQDs/Ag 3 PO 4 @benzoxazine tetrapods, CQDs could not only induce more photocarrier generation from high-energy facets of Ag 3 PO 4 tetrapods but also accelerate the electrons transfer from conduction band of Ag 3 PO 4 tetrapods to the bottom of conduction band of CQDs. Furthermore, silver amine complex could act as a bridge for the photo-electrons flowing from core to shell, which is beneficial to the subsequent free radical chain reaction. In addition, the 3D core-shell structure decreased the solubility of Ag 3 PO 4 . UV–vis DRS, indicating that the band gap of CQDs(0.38%)/Ag 3 PO 4 @benzoxazine (1.65 eV) was far less than that of Ag 3 PO 4 tetrapods (2.0 eV) and traditional Ag 3 PO 4 (2.45 eV). Moreover, the photocurrent tests showed that CQDs(0.38%)/Ag 3 PO 4 @benzoxazine had perfect drift ability of generated photocarriers. Accordingly, the CQDs(0.38%)/Ag 3 PO 4 @benzoxazine tetrapods exhibited excellent visible-light photocatalytic activity and anti-photocorrosion performance. More than 93% of Methylorange and rhodamine B could be photodegraded within 16 min and 10 min over CQDs(0.38%)/Ag 3 PO 4 @benzoxazine tetrapods, respectively. Even after 9 cycles, CQDs(0.38%)/Ag 3 PO 4 @benzoxazine could still remain 95% removal rate of sulfamethoxazole (SMX) with 10 min. Through recycling catalytic experiments and photodegradation pathway explore of SMX, the CQDs(0.38%)/Ag 3 PO 4 @benzoxazine composite suggest its great mineralization capability on sulfonamide antibiotics. The free radicals trapping experiments demonstrated that the holes photoinduced were the main active oxidizing species which played the dominant role in the photocatalytic process. Thus, CQDs(0.38%)/Ag 3 PO 4 @benzoxazine is a promising visible-light responses catalyst for photodegradation of organic pollutants in the environmental protection.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2016
·
IF 8.328
Ning Shao,Jinnan Wang,Dadao Wang,Philippe Corvini
We synthesized novel three-dimensional photocatalyst (Ag 3 PO 4 /TiO 2 @MoS 2 ) with various content of TiO 2 @MoS 2 by electrospining, sequential hydrothermal reaction and chemical deposition. The optimal content of TiO 2 @MoS 2 in Ag 3 PO 4 /TiO 2 @MoS 2 composites is 3.5 wt%, and the bandgap of Ag 3 PO 4 /TiO 2 @MoS 2 (3.5 wt%) (1.85 eV) was much lower than that of pure Ag 3 PO 4 (2.45 eV). Due to high conductivity of TiO 2 @MoS 2 heterostructure, the separation efficiency of electron-hole pairs of Ag 3 PO 4 was significantly improved so that Ag 3 PO 4 /TiO 2 @MoS 2 (3.5 wt%) presented higher photocatalytic activity. More than 92% Methyl orange and Methylene blue were photodegraded over Ag 3 PO 4 /TiO 2 @MoS 2 (3.5 wt%) in 12 min and 5 min, respectively. More importantly,TiO 2 @MoS 2 could play the role of ‘wire’ to guide electrons captured by MoS 2 and quickly transferred electrons into solution so that the recombination of electron-hole pairs and the reduction of silver irons were effectively restrained. Thus, Ag 3 PO 4 /TiO 2 @MoS 2 (3.5 wt%) exhibited excellent anti-photocorrosion performance. Even after 10 cycling runs, Ag 3 PO 4 /TiO 2 @MoS 2 (3.5 wt%) could degrade 75% and 92% of oxytetracycline and enrofloxacin, respectively, whereas Ag 3 PO 4 degraded 23% and 44%. In addition, the possible photodegradation pathways of oxytetracycline and enrofloxacin were proposed, demonstrating that the photodegradation mechanisms involving oxidizing/shedding of functional groups firstly and opening the ring sequentially. Further detection of reactive oxidative species indicated that holes were the main active oxidizing species involved in the photocatalytic reaction process. Thus, Ag 3 PO 4 /TiO 2 @MoS 2 (3.5 wt%) is a promising photocatalyst for photodegradation of organic pollutants in the environmental protection.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2013
·
IF 5.825
Yanhui Zhang,Zhang Chen,Siqi Liu,Yi-Jun Xu
The composites of reduced graphene oxide/ZnO (RGO/ZnO) with different particles size of ZnO have been prepared via a facile solvothermal reaction of graphene oxide (GO) and ZnO in an ethanol-water solvent. It is found that the RGO/ZnO-S1 composite with ZnO particle size of 20–100 nm exhibits the enhanced photoactivity toward degradation of organic dyes and reduction of heavy metal ions Cr(VI) in water as compared to the bare ZnO-S1 sample under UV light irradiation. However, the RGO/ZnO-S2 composite with ZnO particle size of 50–500 nm shows decreased photoactivity as compared to bare ZnO-S2. The recycled photoactivity testing shows that, for RGO/ZnO-S1, the photocorrosion of ZnO-S1 is efficiently inhibited by the hybridization with RGO whereas the case is not for RGO/ZnO-S2. A collection of characterization techniques disclose that the smaller particles size for RGO/ZnO-S1 than that for RGO/ZnO-S2 leads to a more interfacial contact and a chemical bonding between RGO and ZnO-S1, thereby resulting in enhanced photoactivity and efficient anti-photocorrosion as observed for RGO/ZnO-S1. Furthermore, the possible reaction mechanism for degradation of dyes and reduction of Cr(VI) over RGO/ZnO-S1 has also been studied. Our results suggest that the semiconductor particles size has an important effect on the photocatalytic performance of RGO/semiconductor composites photocatalysts. The hybridization of RGO with ZnO in an appropriate manner is able to significantly inhibit the well-known photocorrosion of semiconductor ZnO. It is anticipated that this work would enrich the applications of RGO/semiconductor photocatalysts in environment purification.
研究领域:
材料科学
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环境科学
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纳米技术
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光催化
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水处理
✓ 已验证
DOI
高影响因子
Catalysts
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2020
·Vol. 10
·期 2
·206
·
IF 3.52
Hanxu Zhu,Yekun Ji,Lifang Chen,Weilin Bian,Jinnan Wang
Pt nanowire-anchored dodecahedral Ag3PO4{110} was constructed for organics photodegradation. SEM and TEM images confirmed that the Pt nanowires were grafted on dodecahedral Ag3PO4, which was entirely bounded by {110} facets. All the X-ray diffraction peaks of the samples were indexed to the body-centered cubic phase of Ag3PO4, indicating that Pt nanowire-anchored dodecahedral Ag3PO4well maintained the original crystal structure. The rhombic dodecahedral Ag3PO4entirely bounded by {110} facets achieved high photocatalytic activity. Due to the formation of a Schottky barrier, the Pt nanowires improved the separation of the charge carriers of Ag3PO4. Furthermore, they provided a fast expressway to transfer the photogenerated electrons and prolonged the lifetime of the charge carriers via long-distance transport, resulting in the accumulation of holes on Ag3PO4for organics degradation. More importantly, the Pt nanowires improved the reduction potential of the photogenerated electrons for O2reduction to ·O2−, which enhanced the photocatalytic activity and anti-photocorrosion properties of Ag3PO4. We found that 99.5% of Rhodamine B (RhB) could be removed over 0.5ωt% Pt nanowire-anchored dodecahedral Ag3PO4within 10 min. Even after 10 cycles, the photocatalytic activity was still high. photoluminescence (PL), time-resolved photoluminescence (TRPL), UV–vis diffuse reflectance spectra (UV–visDRS), and photoelectrochemical analysis showed that Pt nanowire-anchored dodecahedral Ag3PO4exhibited lower bandgap, higher photocurrent intensity, better electronic conductivity, and longer charge carriers lifetime than other types of Ag3PO4crystals. Radical trapping experiments and electron paramagnetic resonance (EPR) analysis demonstrated that the holes were the main active species for organics photodegradation.Keywords:Pt nanowire-anchored dodecahedral Ag3PO4{110};anti-photocorrosion;spatial charge carriers’ separation;photogenerated electron utilization;oxygen reduction
研究领域:
材料科学
·
环境科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）