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Journal of Environmental Sciences 2024年第5期139卷 12-22页

作者： Yi Yuan Wen-Long Wang Zhi-Wei Wang Jin Wang Qian-Yuan Wu Key Laboratory of Microorganism Application and Risk Control of Shenzhen Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental SafetyInstitute of Environment and EcologyShenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Shenzhen Environmental Science and New Energy Technology Engineering Laboratory Tsinghua-Berkeley Shenzhen InstituteShenzhen 518055China College of Materials Science and Engineering Shenzhen UniversityShenzhen 518071China

carbon nitride has been extensively used as a visible-light photocatalyst,but it has the disadvantages of a low specific surface area,rapid electron-hole recombination,and relatively low light *** this study,single-atom Ag was successfully anchored on ultrathin carbon nitride(UTCN)via thermal polymerization,the catalyst obtained is called *** Ag hardly changed the carbon nitride's layered and porous physical *** exhibited efficient visible-light photocatalytic performances in the degradation of various recalcitrant pollutants,eliminations of 85% were achieved by visible-light irradiation for *** with Ag improved the photocatalytic performance of UTCN by narrowing the forbidden band gap from 2.49 to 2.36 e V and suppressing electron-hole pair *** addition,Ag doping facilitated O_(2) adsorption on UTCN by decreasing the adsorption energy from -0.2 to -2.22 e V and favored the formation of O_(2)^(·-).Electron spin resonance and radical-quenching experiments showed that O_(2)^(·-)was the major reactive species in the degradation of Acetaminophen(paracetamol,APAP).

关键词： Ag single atom carbon nitride Photocatalysis Visible light Adsorption energy Reactive species

Construction of electron rich Fe active sites by FeCu alloy anchoring on carbon nitride for photocatalytic nitrogen reduction

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Rare Metals 2024年第4期43卷 1570-1579页

作者： Gang Dong Cong Huang Fei-Yang Chen Xue-Qin Liu Zhen Li Xiao-Li Su Tao Zeng Yun-Xia Chen Yi-Huang Chen Yang Wang School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen333403China Faculty of Materials Science and Chemistry China University of GeosciencesWuhan430074China College of Chemistry and Materials Engineering Wenzhou UniversityWenzhou325035China

Given the clean and inexhaustible solar energy from solar light,photocatalytic ammonia synthesis is extremely ***,high electron-hole recombination rates and insufficient active sites severely limited N2 photoreaction ***,we designed and fabricated FeCu alloy nanoparticles anchored on carbon nitride nanosheets with excellent photocatalyt ic ammonia synthesis *** a coupler between Fe and carbon nitride,Cu promotes the separation of photogenerated charge carriers in carbon nitride under solar light irradiation,and renters the semiconductor a forceful electron donor for the Fe active *** accumulated electrons at Fe sites furtherly facilitated the adsorption and activation of the molecular ***,the uniform dispersed FeCu alloy nanoparticles were on carbon nitride nanosheets enhanced the stability of photocataly tic nitrogen reduction reaction,making the artificial photocataly tic ammonia synthesis more sustainable for *** work highlights that a direct electron transfer channel can be used to regulate the photochemical nitrogen fixation network.

关键词： Photocatalytic N_2 fixation carbon nitride FeCu alloy Active sites Hydrogenation pathway

A direct polymeric carbon nitride/tungsten oxide Z-scheme heterostructure for efficient photocatalytic hydrogen generation via reforming of plastics into value-added chemicals

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Rare Metals 2024年第8期43卷 3771-3783页

作者： Rui-Zhe Wang Zhi Lin Yi-Qing Wang Kai-Ni Zhang Ge-Hong Zhang Jie Zhang Samuel S.Mao Shao-Hua Shen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049China School of Civil and Architecture Engineering Xi'an Technological UniversityXi'an 710021China Department of Mechanical Engineering University of California at BerkeleyBerkeleyCA94720USA

To promote charge transfer and separation for efficient photocatalysis,a direct Z-scheme heterostructure was constructed by coupling polymeric carbon nitride(PCN) and WO_(3).Interestingly,the obtained PCN/WO_(3)Z-scheme heterostructure could photocataly tic ally produce hydrogen and value-added chemicals(e.g.,formate and acetate) by reforming of plastic polylactic acid(PLA) in alkaline aqueous *** optimizing WO_(3) contents and reaction conditions,the obtained PCN/WO_(3)heterostructure exhibits much increased photocatalytic activity for PLA photoreforming under visible light,with hydrogen evolution rate reaching 402.90 μmol·g~(-1)·h~(-1),which is 3.5 times that of *** is revealed that the Z-scheme charge transfer between PCN and WO_(3) mainly contributes to the promoted charge separation and thus the improved photocatalytic ***,with h+and·OH experimentally evidenced as the predominant active species,a possible reaction pathway for the reforming of PLA into value-added chemicals(e.g.,formate and acetate)over PCN/WO_(3) Z-scheme heterostructure is cleared by monitoring the reaction intermediates and *** work paves a carbon neutrality and scalable route toward the synergistical production of hydrogen and value-added chemicals by utilizing and recycling plastic waste.

关键词： carbon nitride Z-scheme heterojunction Plastic waste conversion Photocatalytic H_(2)production Value-added chemicals

Synthesis of carbon nitride in potassium hydroxide molten salt for efficient uranium extraction from radioactive wastewater

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 89-99页

作者： Shuang Liu Junhan Luo Daniel-James Maguire Liyuan Zheng Zhe Wang Yuexiang Lu Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Nuclear Research Institute for Future Technology and Policy Seoul National UniversitySeoul 08826Republic of Korea Department of Earth Sciences University of CambridgeCambridge CB23EQUK The MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and EngineeringNorth China Electric Power UniversityBeijing 102206China

Photocatalysis-assisted removal of uranium has been proven as an effective method for the elimination of radioactive pollution from *** this work,carbon nitride materials were synthesized in potassium hydroxide(KOH)molten salt and applied to photocatalytic uranyl *** materials were confirmed to possess the triazine-s-heptazine structure by NMR,XPS and UV-Vis characterization,and exhibited a wider visible light absorption than graphitic carbon nitride(g-C_(3)N_(4)).The photocatalytic activity of the carbon nitride materials was tailored by varying the precursor mass *** carbon nitride obtained at 80%melamine as precursor(K-CN-80)exhibited the highest photocatalytic extraction ability and its photocatalytic reaction rate is 6.6 times faster than that of g-C_(3)N_(4).The influence of sacrificial agents was studied and the results showed that triethanolamine inhibited U(Ⅵ)photoreduction,but methanol can accelerate U(Ⅵ)photoreduction by consuming photogenerated *** unary KOH molten salt synthesis method has exceptional potential applications in the preparation of carbon nitrides,and the obtained products showed potential in extracting U(Ⅵ)from aqueous solutions for use in nuclear fuel industry and for U(Ⅵ)environmental pollution cleanup.

关键词： Uranium carbon nitride Molten salt Photocatalysis Radioactive wastewater

Advances in Polymeric carbon nitride Photocatalysts for Enhanced CO_(2)Reduction

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 1-12页

作者： Liu Bing Sun Shangcong Song Ye Peng Bo Lin Wei SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing100083China

Photocatalysis has emerged as a promising alternative for converting and utilizing CO_(2).Polymeric carbon nitride(PCN),typically synthesized through the one-step thermal polycondensation of nitrogen-rich precursors,has shown considerable promise due to its adjustable band structure and inherent *** the past five years,significant literature in this field has identified five primary methods for modifying PCN:morphology modulation,element doping,defect induction,co-catalyst loading,and heterojunction construction.A detailed discussion on how each modification method influences light absorption,charge separation,and surface reaction efficiencies in photocatalysis is *** on these findings,several future directions for the development of PCN-based materials are proposed,such as designing tailored PCN structures for specific photocatalytic reactions and using theoretical calculations to verify and correct results from current characterization *** the challenges associated with the large-scale synthesis of PCN materials with controllable structures and satisfactory performance,this work offers valuable insights for advancing photocatalytic PCN-based systems for large-scale solar fuel production.

关键词： carbon nitride photocatalysis CO_(2)reduction modification

Advanced carbon nitride-based single-atomphotocatalysts

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SusMat 2024年第5期4卷 70-113页

作者： Zifan Zhang Kun Xiang HaitaoWang Xin Li Jing Zou Guijie Liang Jizhou Jiang School of Environmental Ecology and Biological Engineering School of Chemistry and Environmental EngineeringKey Laboratory of Green Chemical Engineering Process of Ministry of EducationEngineering Research Center of Phosphorus Resources Development and Utilization of Ministry of EducationNovel Catalytic Materials of Hubei Engineering Research CenterWuhan Institute of TechnologyWuhanChina Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhouChina Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyangChina

Single-atom catalysts(SACs)have rapidly become a hot topic in photocatalytic research due to their unique physical and chemical properties,high activity,and high *** many semiconductor carriers,the special structure of carbon nitride(C3N4)perfectly meets the substrate requirements for stabi-lizing SACs;they can also compensate for the photocatalytic defects of C3N4 materials by modifying energy bands and electronic ***,devel-oping advanced C3N4-based SACs is of great *** this review,we focus on elucidating efficient preparation strategies and the burgeoning photo-catalytic applications of C3N4-based *** also outline prospective strategies for enhancing the performance of SACs and C3N4-based SACs in the future.A comprehensive array of methodologies is presented for identifying and char-acterizing C3N4-based *** includes an exploration of potential atomic catalytic mechanisms through the simulation and regulation of atomic catalytic behaviors and the synergistic effects of single or multiple ***,a forward-looking perspective is adopted to contemplate the future prospects and challenges associated with C3N4-based *** encompasses considerations,such as atomic loading,regulatory design,and the integration of machine learn-ing *** is anticipated that this review will stimulate novel insights into the synthesis of high-load and durable SACs,thereby providing theoretical groundwork for scalable and controllable applications in the field.

关键词： atomic catalytic mechanism carbon nitride improvement strategies photocatalytic applica-tions single-atom catalysts

Defect and nanostructure engineering of polymeric carbon nitride for visible-light-driven CO2 reduction

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carbon nitride with encapsulated nickel for semi-hydrogenation of acetylene: pyridinic nitrogen is responsible for hydrogen dissociative adsorption

结构化学 2024年第3期43卷 10-18页

作者： Ziruo Zhou Wenyu Guo Tingyu Yang Dandan Zheng Yuanxing Fang Xiahui Lin Yidong Hou Guigang Zhang Sibo Wang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou350116China College of Environment and Safety Engineering Fuzhou UniversityFuzhou350108China

Sunlight-induced photocatalytic carbon dioxide(CO2)reduction to energy-rich chemicals by metal-free polymeric carbon nitride(CN)semiconductor is a promising tactic for sustained solar fuel ***,the reaction efficiency of CO2 photoreduction is restrained seriously by the rapid recombination of photogenerated carriers on CN ***,we incorporate 2-aminopyridine molecule with strong electron-withdrawing group into the skeleton edge of CN layers through a facile one-pot thermal polymerization strategy using urea as the precursor,which renders a modified carbon nitride(ACN)with extended optical harvesting,abundant nitrogen defects and ultrathin nanosheet ***,the ACN photocatalyst with desirable structural features attains enhanced separation and migration of photoexcited charge *** visible light irradiation with Co(bpy)32+as a cocatalyst,the optimized ACN sample manifests a high CO2 deoxygnative reduction activity and high sta-bility,providing a CO yielding rate of 17 μmol h-1,which is significantly higher than that of pristine *** key intermediates engaged in CO2 photoreduction reaction are determined by the in situ diffuse reflectance infrared Fourier transform spectroscopy,which sponsors the construction of the possible photocatalytic CO2 reduction mechanism on ACN nanosheets.

关键词： carbon nitride Photocatalysis CO_2 reduction Nitrogen defects Nanosheets

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Science China Chemistry 2018年第8期61卷 1014-1019页

作者： Teng Fu Tao Wang Hongfang Sun Yida Xu Zhen Dong Xiangke Guo Luming Peng Yan Zhu Zhaoxu Chen Weiping Ding Key Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical Engineering Nanjing University

A new mechanism of catalyst has been demonstrated in this article. With the interaction between carbon nitride(CN) and encapsulated nickel, the CN in the catalyst has been endowed with new active sites for the adsorption and activation of hydrogen while nickel itself is physically isolated from the contact with reactive molecules. For the selective hydrogenation of acetylene in large amount of ethylene, the catalyst shows excellent ethylene selectivity than the nickel catalyst itself, which is almost totally unselective. Meanwhile, the CN itself is inactive for the reaction. The results of characterization demonstrate that pyridinic nitrogen doped in the carbon matrix should be the active sites for hydrogen dissociative adsorption. The theoretical calculations further confirm the results and provide with the detail in the electron transfer between nickel and CN in the catalyst. The current results supply a new concept for design of high performance catalyst.

关键词： carbon nitride nickel selective hydrogenation acetylene pyridinic nitrogen

carbon nitride Films Deposited on Pt Substrates byMicrowave Plasma Chemical Vapor Deposition

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 42-44页

作者： Yongping Zhang Yousong Gu Xiangrong Chang Zhongzhuo Tian Dongxia Shi Xiufang Zhanga Lei Yuan Material Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China Beijing Laboratory of Vacuum Physics, Institut Material Science and Engineering School University of Science and Technology Beijing Beijing 100083 China Beijing Laboratory of Vacuum Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

carbon nitride thin films have been synthesized on polycrystalline Pt substrates using microwave plasma chemical vapor de- position (MPCVD) technique. The N/C atomic ratio is close to the stoichiometric value 1.33 of C_3N_4. The experimental X-ray diffraction spectra contain all the strong peaks of α-C_3N_4 and β -C_3N_4. The films are a mixture of α-C_3N_4 and β -C_3N_4. The observed Raman and FT- IR spectra support the existence of C-N covalent bond in carbon nitride compound. The bulk modulus detected by Nano II nanoindentor is up to 349 GPa.

关键词： carbon nitride MPCVD, thin film deposition

carbon nitride transparent counter electrode prepared by magnetron sputtering for a dye-sensitized solar cell

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Green Energy & Environment 2017年第3期2卷 302-309页

作者： Chaoyu Wu Guoran Li Xueqin Cao Bao Lei Xueping Gao Institute of New Energy Material Chemistry School of Materials Science and Engineering National Institure for Advanced Materials Nankai University Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin Key Laboratory of Metal and Molecule Based Material ChemistryNankai University

carbon nitride(CN_x) films supported on fluorine-doped tin oxide(FTO) glass are prepared by radio frequency magnetron sputtering, in which the film thicknesses are 90-100 nm, and the element components in the CNX films are in the range of x = 0.15-0.25. The as-prepared CN_x is for the first time used as counter electrode for dye-sensitized solar cells(DSSCs), and show a preparation-temperature dependent electrochemical performance. X-ray photoelectron spectroscopy(XPS) demonstrates that there is a higher proportion of sp^2 C=C and sp^3 C-N hybridized bonds in CN_x-500(the sample treated at 500 ℃) than in CNX-RT(the sample without a heat treatment). It is proposed that the sp^2 C=C and sp^3 C-N hybridized bonds in the CN_x films are helpful for improving the electrocatalytic activities in DSSCs. Meanwhile, Raman spectra also prove that CN_x-500 has a relatively high graphitization level that means an increasing electrical conductivity. This further explains why the sample after the heat treatment has a higher electrochemical performance in DSSCs. In addition, the as-prepared CN_x counter electrodes have a good light transmittance in the visible light region. The results are meaningful for developing low-cost metal-free transparent counter electrodes for DSSCs.

关键词： Solar cells Counter electrodes carbon nitride Electrocatalysis Magnetron sputtering