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Qiao Wang

Bio: Qiao Wang is an academic researcher from Harbin Institute of Technology. The author has contributed to research in topics: Photocatalysis & Catalysis. The author has an hindex of 21, co-authored 48 publications receiving 1636 citations. Previous affiliations of Qiao Wang include Qingdao Agricultural University & Guangdong University of Technology.

Papers
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Journal ArticleDOI
TL;DR: In this paper, a novel oxygen vacancy-rich two-dimensional/two-dimensional (2D/2D) BiOCl-g-C3N4 ultrathin heterostructure nanosheet (CN-BC) was successfully prepared by a facile solvothermal method for degradation of non-dye organic contaminants.
Abstract: Photocatalytic degradation has been unearthed as a promising strategy for environmental remediation, and the calling is endless for more efficient photocatalytic system. In this study, a novel oxygen vacancy-rich two-dimensional/two-dimensional (2D/2D) BiOCl-g-C3N4 ultrathin heterostructure nanosheet (CN-BC) is successfully prepared by a facile solvothermal method for degradation of non-dye organic contaminants. HRTEM observes the formation of heterojunction, while ESR and XPS unveil the distinct oxygen vacancy concentrations. Density functional calculations reveal that the introduction of oxygen vacancies (OVs) brings a new defect level, resulting in the increased photoabsorption. Under visible light irradiation, the OVs-rich optimum ratio of CN-BC (50CN-50BC) Exhibits 95% removal efficiency of 4-chlorophenol within 2 h, which is about 12.5, 5.3 and 3.4 times as that of pure BiOCl, g-C3N4 and OVs-poor heterostructure, respectively. The photocatalytic mechanism of OVs-rich 50CN-50BC is also revealed, suggesting that the synergistic effect between 2D/2D heterojunction and oxygen vacancies greatly promotes visible-light photoabsorption and photoinduced carrier separation efficiency with a prolonged lifetime, which is confirmed by multiple optical and electrochemical analyses, including DRS, steady-state photoluminescence spectra, electrochemical impedance spectroscopy, photocurrent response and time-resolved fluorescence spectra. This study could bring new opportunities for the rational design of highly efficient photocatalysts by combining 2D/2D heterojunctions with oxygen vacancies in environmental remediation.

451 citations

Journal ArticleDOI
Limin Hu1, Guangshan Zhang1, Meng Liu1, Qiao Wang1, Peng Wang1 
TL;DR: In this article, a novel Co3O4-Bi2O3 catalyst was synthesized using a microwave-assistant method, and the corresponding characteristics were studied through XRD, SEM, and N2 adsorption.

313 citations

Journal ArticleDOI
TL;DR: In this article, a CuO coated ceramic hollow fiber membrane with dual functionalities of membrane filtration and peroxymonosulfate (PMS) activation was successfully constructed by applying phase-inversion and dip-coating technologies.
Abstract: A CuO coated ceramic hollow fiber membrane with dual functionalities of membrane filtration and peroxymonosulfate (PMS) activation was successfully constructed by applying phase-inversion and dip-coating technologies. The CuO coating condition was investigated, and the optimized CuO coated ceramic hollow fiber membranes (CuO@CHFMs) exhibited excellent catalytic activity for PMS activation to depredate bisphenol A (BPA) in the presence of humic acid (HA), chloride ions (Cl−) and bicarbonate (HCO3−). Based on the scavenger experiments and electron paramagnetic resonance (EPR) analyses, the non-radical reactive oxygen species - singlet oxygen (1O2), rather than sulfate radicals (SO4•-) or hydroxyl radicals (•OH), was elucidated as the primary reactive species responsible for the oxidation of BPA in the system. The redox circles of Cu(II)/Cu(I) on the CuO surface of the CuO@CHFMs are mainly responsible for PMS activation and a possible degradation pathway of BPA was proposed. Moreover, the CuO@CHFMs exhibited excellent stability and reusability without tedious catalyst separation/recovery processes. This study is meaningful for the development of novel catalytic membrane with PMS activation functionality in water treatment.

207 citations

Journal ArticleDOI
TL;DR: In this article, a series of oxygen vacancy-rich ultrathin two-dimensional BiOBrxI1-x solid solution nanosheets (BBI-x) were successfully constructed via a one-step solvothermal method.
Abstract: Photocatalysis is intensively investigated for environmental remediation, but suffering from moderate efficiency toward the colorless persistent organic contaminants, the major category of organic pollutants in water environment. Herein, a novel series of oxygen vacancy-rich ultrathin two-dimensional BiOBrxI1-x solid solution nanosheets (BBI-x) were successfully constructed via a one-step solvothermal method. Under visible light irradiation, the optimal BiOBr0.85I0.15 sample (BBI-0.85) exhibited over 90% degradation efficiency of 4-chlorophenol (4-CP) within 30 min, which was 4.4, 10.9 and 5.9 times greater than that of pure BiOI nanosheets, pure BiOBr nanosheets and oxygen vacancy-poor BiOBr0.85I0.15 nanoplates, respectively. Also, this excellent photoactivity can expand to other colorless organic contaminants, such as bisphenol analogues and sulfonamides, verifying the universal applicability of BiOBrxI1-x. The enhanced activity can be ascribed to the synergistic effect of solid solution and oxygen vacancies. Formation of solid solution promotes visible-light harvesting and photogenerated charge carriers’ separation efficiency, as well as endows photoinduced holes with sufficient oxidation capacity, unambiguously confirmed by multiple optical and photoelectrochemical characterizations. Meanwhile, the oxygen vacancies induce an intermediate level near the Fermi level, narrowing the band gap energy and impeding the recombination of photogenerated charge carriers, as evidenced by density functional theory (DFT) analyses. This work could give ideas for the design of highly active photocatalysts toward sustainable solar-to-chemical energy conversion and environmental remediation.

175 citations

Journal ArticleDOI
TL;DR: A novel Co 3 O 4 -Bi 2 O 3 /PMS/BPA catalyst was synthesized by a microwave-assisted co-precipitation method and systematically characterized with multifarious techniques to investigate its crystallinity, morphology and chemical state as mentioned in this paper.

133 citations


Cited by
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TL;DR: Recently, due to the attractive properties such as appropriate band structure, ultrahigh specific surface area, and more exposed active sites, two-dimensional (2D) photocatalysts have attracted significant attention as discussed by the authors.
Abstract: Hydrogen generation from the direct splitting of water by photocatalysis is regarded as a promising and renewable solution for the energy crisis The key to realize this reaction is to find an efficient and robust photocatalyst that ideally makes use of the energy from sunlight Recently, due to the attractive properties such as appropriate band structure, ultrahigh specific surface area, and more exposed active sites, two-dimensional (2D) photocatalysts have attracted significant attention for photocatalytic water splitting This Review attempts to summarize recent progress in the fabrication and applications of 2D photocatalysts including graphene-based photocatalysts, 2D oxides, 2D chalcogenides, 2D carbon nitride, and some other emerging 2D materials for water splitting The construction strategies and characterization techniques for 2D/2D photocatalysts are summarized Particular attention has been paid to the role of 2D/2D interfaces in these 2D photocatalysts as the interfaces and heterojunctions a

717 citations

Journal ArticleDOI
TL;DR: The fundamentals, advantages and disadvantages of single and coupled Fenton optimization processes for organic wastewater treatment were reviewed, and some important operation parameters on the degradation efficiency of organic pollutants was studied to provide guidance for the optimization of operation parameters.

598 citations

Journal ArticleDOI
TL;DR: In this article, a solvent evaporation induced self-assembly method was employed to prepare a novel S-scheme heterojunction composite by combining sulfur-doped porous graphite carbon nitride (S-pCN) with tungsten oxide (WO2.72) semiconductors which manifest effective interface contact and excellent photocatalytic performance.

404 citations

Journal ArticleDOI
TL;DR: In this paper, a photo-catalytic performance of α-Fe 2 O 3 anchored to graphene oxide (GO) nanosheet was evaluated in a heterogeneous Fenton system.
Abstract: Novel hybrid nanostructures or nanocomposites are receiving increasing attention due to their newly evolved properties. In this work, α-Fe 2 O 3 anchored to graphene oxide (GO) nanosheet (α-Fe 2 O 3 @GO) was synthesized through a facile hydrolysis process and its photo-catalytic performances and durability in heterogeneous Fenton system were fully evaluated. The decolorization rates of methylene blue in α-Fe 2 O 3 @GO + H 2 O 2 + UV system within a wide pH range were approximately 2.9-fold that of classical Degussa P25 TiO 2 + UV and 2.4-fold that of α-Fe 2 O 3 + H 2 O 2 + UV. This enhanced decolorization of methylene blue (MB) in α-Fe 2 O 3 @GO + H 2 O 2 + UV system were attributed to the unique incorporation of GO into the catalyst which not only mediated the morphology of active sites α-Fe 2 O 3 nanoparticles but also offered high electron conductivity and electrostatic attraction between negatively charged GO with positively charged MB. High efficiencies of degradation were achieved on various surface charged organic pollutants (around 96–100%), such as cationic compounds of MB and rhodamine B (RhB), anionic compound Orange II (OII) and Orange G (OG), neutral compounds of phenol, 2-nitrophenol (2-NP) and endocrine disrupting compound 17β-estradiol (E2). The dominant reactive oxygen species (ROS) responsible for decolorization, such as hydroxyl radicals ( OH) and superoxide anion radicals (O 2 − ) generated by activation of H 2 O 2 on the surface of α-Fe 2 O 3 @GO were detected and quantified by free radical quenching methods. The possible degradation mechanism of MB involved the rupture of phenothiazine ring by desulfurization and the rupture of phenyl ring due to the attack of ROS, which was analyzed by LC/MS/MS. The reduction of MB and its intermediates was consistent with the decreasing trend of the acute toxicity towards luminous bacteria with the increasing irradiation time. The results lay a foundation for highly effective and durable photo-Fenton technologies for organic wastewater within wider pH ranges than the conventional photo-Fenton reaction.

362 citations

Journal ArticleDOI
TL;DR: In this paper, the authors summarize new progress in the development of metal nanoparticle (NP) catalysts, which are categorized into monometallic and heterometallic catalysts with excellent activity and high recyclability for different AB dehydrogenation pathways.
Abstract: Ammonia borane (AB), having a high hydrogen density of 19.6 wt %, has attracted much attention as a promising chemical hydrogen storage material. In the past few years, a number of highly active metal nanoparticle (NP) catalysts, which are easy to handle and separate, have been developed for AB dehydrogenation. In this Perspective, we summarize new progress in the development of metal NP catalysts, which are categorized into monometallic and heterometallic catalysts, with excellent activity and high recyclability for different AB dehydrogenation pathways, including solvolysis (hydrolysis and methanolysis) in protic solvents and dehydrocoupling in nonprotic solvents, and we survey the corresponding methods for the regeneration of AB. Moreover, the merits and drawbacks of solvolysis and dehydrocoupling are discussed.

344 citations