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Advances in Nanoparticles 2019年第1期8卷 1-19页

作者： Sankaran Murugesan Oleksandr Kuznetsov Zhou Zhou Valery Khabashesku Center for Technology Innovation Baker Hughes a GE Company Houston USA

Synthesis and characterization of hybrid fluorescent superparamagnetic core-shell particles of Fe@C-CNx composition are presented for the first time. The prepared Fe@C-CNx hybrid nanoparticles were found to possess multifunctionality by exhibiting strong superparamagnetic properties and bright fluorescence emissions at 500 nm after the excitation with light in the UV-visible range. Fe@C-CNx also exhibits photocatalytic activities for organic dye degradation comparable to pure amorphous CNx with reusability through magnetic separation. The combination of magnetic and fluorescent properties of core-shell Fe@C-CNx nanoparticles opens opportunities for their application as sensors and magnet manipulated reusable photocatalysts. Superparamagnetic Fe@C core-shell nanoparticles were used as the template material in the synthesis, where the carbon shell was functionalized through one-step free-radical addition of alkyl groups terminated with carboxylic acid moieties. The method utilizes the organic acyl peroxide of dicarboxylic acid (succinic acid peroxide) as a non-oxidant functional free radical precursor for functionalization. Further, covalently functionalized succinyl-Fe@C core-shell nanoparticles were coated with the amorphous carbon nitride (CNx) generated by an in-situ solution-based chemical reaction of cyanuric chloride with lithium nitride. A detailed physicochemical characterization of the microstructure, magnetic and fluorescence properties of the synthesized hybrid nanoparticles is provided.

关键词： Magnetic Nanoparticles Core-Shell Nanostructures Fe@C-CNx Fluorescence photocatalysts

Facile synthesis of C_(3)N_(4)-supported metal catalysts for efficient CO_(2) photoreduction

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Nano Research 2022年第1期15卷 551-556页

作者： Yun-Nan Gong Bi-Zhu Shao Jian-Hua Mei Wei Yang Di-Chang Zhong Tong-Bu Lu Institute for New Energy Materials and Low Carbon Technologies School of Materials Science and EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China Key Laboratory of Jiangxi University for Functional Material Chemistry College of Chemistry&Chemical EngineeringGannan Normal UniversityGanzhou 341000China

Facile synthesis of photocatalysts with highly dispersed metal centers is a high-priority target yet still a significant *** this work,a series of Co-C_(3)N_(4) photocatalysts with different Co contents atomically dispersed on g-CaN4 have been prepared via one-step thermal treatment of cobalt-based metal-organic frameworks(MOFs)and urea in the *** to the highly dispersed and rich exposed Co sites,as well as good charge separation efficiency and abundant mesopores,the optimal 25-Co-C_(3)N_(4),in the absence of noble metal catalysts/sensitizers,exhibits excellent performance for photocatalytic C0_(2) reduction to CO under *** irradiation,with a high CO evolution rate of 394.4μmol·g^(-1)·h^(-1),over 80 times higher than that of pure g-C_(3)N_(4)(4.9μmol·g^(-1)·h^(-1)).In:addition,by this facile synthesis strategy,the atomically dispersed Fe and Mn anchoring on g-C_(3)N_(4)(Fe-C_(3)N_(4) and Mn-C_(3)N_(4))have been also obtained,indicating the reliability and universality of this strategy in synthesizing photocatalysts with highly dispersed metal *** work paves a new way to develop cost-effective photocatalysts for photocatalytic C0_(2) reduction.

关键词： metal-organic frameworks highly dispersed metal g-C_(3)N_(4) photocatalysts C02 reduction

Facile synthesis and superior photocatalytic and electrocatalytic performances of porous B-doped g-C_3N_4 nanosheets

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Journal of Materials Science & Technology 2018年第12期34卷 2515-2520页

作者： Qian Yan Gui-Fang Huang Dong-Feng Li Ming Zhang An-Lian Pan Wei-Qing Huang Department of Applied Physics School of Physics and ElectronicsHunan University

As a low-cost visible-light-driven metal-free catalyst, graphitic carbon nitride(g-CN) has attracted increasing attention due to its wide applications for solar energy conversion, environmental purification,and organic photosynthesis. In particular, the catalytic performance of g-CNcan be easily modulated by modifying morphology, doping, and copolymerization. Simultaneous optimization, however, has little been achieved. Herein, a facile one-pot strategy is developed to synthesize porous B-doped g-CNnanosheets by using HBOand urea as the precursor during thermal polymerization. The resultant B-doped g-CNnanosheets retain the original framework of bulk g-CN, while induce prominently enhanced visible light harvesting and narrowing band gap by 0.32 eV compared to pure g-CN. Moreover, the adsorption capacity and photodegradation kinetics of methylene blue(MB) under visible light irradiation over B-doped g-CNnanosheets can be improved by 20.5 and 17 times, respectively. The synthesized porous B-doped g-CNnanosheets also exhibit higher activities than pure g-CNas bifunctional electrocatalyst for both oxygen evolution reaction(OER) and oxygen reduction reaction(ORR). The enhanced catalyst performance of porous B-doped g-CNnanosheets stems from the strong synergistic effect originating from the larger exposed active sites generated by the exfoliation of g-CNinto nanosheets and the porous structure, as well as the better conductivity owing to B-doping. This work provides a simple, effective, and robust method for the synthesis of g-CN-based nanomaterial with superior properties to meet the needs of various applications.

关键词： B-doped g-C_3N_4 nanosheets photocatalysts Electrocatalysts

Countering microplastics pollution with photocatalysis: Challenge and prospects

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Progress in Natural Science:Materials International 2023年第3期33卷 251-266页

作者： Runjing Xu Lifeng Cui Shifei Kang School of Environment and Architecture University of Shanghai for Science and Technology College of Smart Energy Shanghai Jiao Tong University Institute of Photochemistry and Photofunctional Materials (IPPM) University of Shanghai for Science and Technology

The rapid increase in plastic production and disposal worldwide has adversely and significantly impacted the global environment and biology. Traditional treatment methods are not appropriate for microplastics(MPs) due to their highly polymerized, stable, and complex chemical structure. Photocatalytic degradation of MPs is a relatively new and environmentally friendly approach. This review summarizes the common sources and types of MPs, and covers the various strategies and methods for degrading MPs. It describes the recent developments in the photocatalytic degradation of MPs by transition metals catalysts as well as noble metal catalysts, and discusses the characteristics and limitations of each type of catalyst. It was found out that some photo-catalysts showed very good performance for degradation of MPs, but many of the literature failed to clarify the bond-breaking mechanism during photocatalytic reaction. This review tries to elucidate the bond-breaking mechanisms of various types of MP in photocatalytic process. Advice for future research directions is proposed by investigating the knowledge gaps between those reported literature. The main purpose of this review is to provide a comprehensive summarization for the current research status of photocatalytic degradation of MPs. This work may help researchers explore new photocatalytic methods for future MP control.

关键词： Microplastics Photocatalytic degradation photocatalysts Bond break mechanism

Photocatalytic Degradation of Rhodamine B by Recyclable Ag Br/Polypyrrole(PPy)Nano-Catalysts

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1198-1204页

作者： YIN Xiaogang LIU Xinyun LI Hang WU Huimin FU Hai GONG Wei Key Laboratory of Functional Materials Chemistry of Gui Zhou Province School of Chemistry and Materials ScienceGui Zhou Normal UniversityGuiyang 550001China School of Pharmaceutical Sciences Guizhou Medical UniversityGuiyang 550025China

We investigated the removal of the organic dye rhodamine B in wastewater with recyclable AgBr/polypyrrole(PPy)*** PPy as an active base for electron transfer,and hexadecyltrimethylammonium bromide(CTAB)as both the soft-templating agent and the bromine source,a series of AgBr/PPy nano-photocatalysts containing various proportions of silver were prepared in a convenient one-step synthesis *** synthesized catalysts were characterized by TG analysis to reveal that,in comparison with pure PPy,the interaction between PPy and AgBr led to increased thermal *** combination of PPy and AgBr was observed through XRD and XPS *** the morphology study,the AgBr particles were found to be well dispersed in the PPy nanowire network from SEM *** the photodegradation experiments,up to 92%rhodamine B was degraded by the AgBr/PPy catalysts in the period of 1 hour under 254 nm UV *** catalysts could maintain 60%catalytic efficiency after 3 cycles in the recyclability test.

关键词： polypyrrole AgBr photocatalysts rhodamine B

Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 4908-4915页

作者： Xu Han Xueying Ge Wen-Wen He Wangwang Shen Tao Zhou Jian-Sen Wang Rong-Lin Zhong Abdullah MAl-Enizi Ayman Nafady Shengqian Ma School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China Department of Chemistry University of North Texas1508 W.Mulberry St.DentonTX 76201USA Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen *** this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active *** fabricated PtNPs@covalent triazine-based framework-1(CTF-1)composite accomplished a significantly high rate of hydrogen evolution(20.0 mmol·g^(−1)·h^(−1),apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine *** calculations revealed that the strong electron transfer(Q(Pt)=−0.726 qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1,and qe is the unit of charge transfer quantity)between PtNPs and CTF-1 triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1,thereby enabling high stability and excellent hydrogen production ***,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1 is much lower than that of the unmodified CTF-1,leading to a much lower intermediate state and hence a significant improvement in photocatalytic *** overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts.

关键词： Pt nanoparticles covalent triazine-based framework-1(CTF-1) photocatalysts hydrogen evolution reaction

A novel Z-scheme CeO_(2)/g-C_(3)N_(4)heterojunction photocatalyst for degradation of Bisphenol A and hydrogen evolution and insight of the photocatalysis mechanism

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Journal of Materials Science & Technology 2021年第26期85卷 18-29页

作者： Wei Zhao Tiantian She Jingyi Zhang Guoxiang Wang Sujuan Zhang Wei Wei Gang Yang Lili Zhang Dehua Xia Zhipeng Cheng Haibao Huang Dennis Y.C.Leung School of Geography School of EnvironmentNanjing Normal UniversityNanjing210000China Jiangsu Collaborative Innovation Center of Regional Modern Agriculture&Environmental Protection School of Chemistry and Chemical EngineeringHuaiyin Normal UniversityHuaian223001China School of Materials Engineering Changshu Institute of TechnologyChangshu215500China Department of Mechanical Engineering The University of Hong Kong999077Hong KongChina School of Environmental Science and Engineering Sun Yat-Sen UniversityGuangzhou510000China Huaibei Normal University Huaibei235000China

CeO_(2)/g-C_(3)N_(4)heterojunction photocatalyst had been successfully fabricated through a one-step in-situ pyrolysis formation of 3D hollow CeO_(2)mesoporous nanospheres and 2D g-C_(3)N_(4)nanosheets together with simultaneous removal of carbon sphere templates after heat *** sample shows high catalytic performances for photocatalytic hydrogen generation and photocatalytic oxidation of Bisphenol A(BPA)under visible light irradiation,and the catalytic degradation route of BPA was suggested by the degradation products determined by *** enhancing catalytic activity was attributed to the effective interfacial charge migration and ***,it was proposed that the CeO_(2)/g-C_(3)N_(4)heterojunction photocatalyst could follow a more appropriate Z-scheme charge transfer mechanism,which was confirmed by the analysis of experiment and theoretical calculation results.

关键词： Heterojunction photocatalysts Hydrogen generation Charge separation

Enhancing solar-driven overall water splitting via both sacrifice and noble metal free photocatalysis: copper cluster/boron-doped carbon nitride catalysts

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Science China Chemistry 2024年第11期67卷 3886-3896页

作者： Yun-Dong Cao Yuxi Zhang Jian Song Hong Liu Zhiyuan Song Lin-Lin Fan Cai-Li Lv Guang-Gang Gao School of Materials Science and Engineering University of JinanJinan 250022China

The major impediment to the additional industrialization of water splitting is the high cost of the co-catalyst made of noble metals and the sacrificial reagent. A binary photocatalytic system, consisting of B-doped g-C_(3)N_(4) nanosheets(Cu_(20)@BCN-X) and atomically accurate copper clusters, is designed in this study. The copper clusters serve as co-catalysts for H_(2) evolution and exhibit Pt-like activity, whereas the nanosheets serve as carriers and semiconductor components for O_(2) evolution. Such binary system, created using simple techniques, demonstrates hydrogen bonding interactions that promote synergistic effects and efficient binding and charge transfer across the interface between the two components. Band position manipulation of carbon nitride nanosheets demonstrates a Z-scheme charge transfer mechanism between the nanosheets and copper clusters. This photocatalytic system can accomplish the photocatalytic overall water splitting process(259.9 μmol g^(-1)h^(-1)of H_(2) and 129.4 μmol g^(-1)h^(-1)of O_(2)) without using sacrificial agents or noble metal co-catalysts. This work lays the foundation for the design of overall water splitting catalysts by precisely manipulating the energy levels, and it also paves the way for commercialized photocatalytic catalysts that do not require noble metals or sacrificial chemicals.

关键词： copper clusters band modulation photocatalysts water splitting

Covalent-organic frameworks with keto-enol tautomerism for efficient photocatalytic oxidative coupling of amines to imines under visible light

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Science China Chemistry 2021年第12期64卷 2169-2179页

作者： Zhenyu Wu Xiubing Huang Xiangjun Li Guangtong Hai Baozhen Li Ge Wang Beijing Advanced Innovation Center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule&Structure ConstructionSchool of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China

Photocatalytic oxidation of organic molecules into highly value-added products is an innovative and challenging research which has gradually attracted remarkable attention of *** this work,it is demonstrated that the COF-TpPa with keto-enol tautomerism equilibrium structure shows excellent performance(yield>99%after 8 h)in the selective photocatalytic oxidative coupling of amines to imines under visible light *** is revealed that three kinds of reactive oxygen species(superoxide radical,hydroxyl radical and singlet oxygen)participate in this photocatalytic oxidation *** addition,hydrogen protons cleaved from the benzyl are proven to be reduced to hydrogen in the conduction band of COF-TpPa in anaerobic atmosphere,accompanied with the formation of *** direct hydrogen evolution from amine provides an effective way to extract clean energy from organic molecule as well as the production of value-added *** a contrast,COF-LZU1 with similar structure and chemical composition to COF-TpPa but without keto-enol tautomerism exhibits worse optical properties and photocatalytic *** is also demonstrated that keto-enol tautomerism favors the adsorption of benzylamine based on the characterization results and theoretical calculations.

关键词： covalent-organic frameworks photocatalysts aerobic/anaerobic benzylamine oxidation keto-enol tautomerism

Photocatalytic and Electrocatalytic Generation of Hydrogen Peroxide: Principles, Catalyst Design and Performance

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Nano-Micro Letters 2023年第6期15卷 24-72页

作者： Yan Guo Xili Tong Nianjun Yang State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China Institute of Materials Engineering University of Siegen57076 SiegenGermany Department of Chemistry Hasselt University3590 DiepenbeekBelgium IMO‑IMOMEC Hasselt University3590 DiepenbeekBelgium

Hydrogen peroxide(H_(2)O_(2)) is a high-demand organic chemical reagent and has been widely used in various modern industrial applications. Currently,the prominent method for the preparation of H_(2)O_(2) is the anthraquinone ***, it is not conducive to economic and sustainable development since it is a complex process and involves unfriendly environment and potential hazards. In this context, numerous approaches have been developed to synthesize H_(2)O_(2). Among them, photo/electro-catalytic ones are considered as two of the most promising manners for on-site synthesis of H_(2)O_(2). These alternatives are sustainable in that only water or O_(2) is required. Namely, water oxidation(WOR) or oxygen reduction(ORR)reactions can be further coupled with clean and sustainable energy. For photo/electro-catalytic reactions for H_(2)O_(2) generation, the design of the catalysts is extremely important and has been extensively conducted with an aim to obtain ultimate catalytic performance. This article overviews the basic principles of WOR and ORR,followed by the summary of recent progresses and achievements on the design and performance of various photo/electro-catalysts for H_(2)O_(2) generation. The related mechanisms for these approaches are highlighted from theoretical and experimental aspects. Scientific challenges and opportunities of engineering photo/electro-catalysts for H_(2)O_(2) generation are also outlined and discussed.

关键词： H_(2)O_(2)generation photocatalysts Electrocatalysts Reaction mechanisms