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Nano Research 2024年第4期17卷 3413-3422页

作者： Huimei Chen Yan Yang Chi Jiao Zhiwen Zhuo Junjie Mao Yan Liu Key Laboratory of Functional Molecular Solids Ministry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002China

The electrocatalytic nitrogen reduction reaction(e-NRR)is a promising alternative method for the Haber–Bosch process.However,it still faces many challenges in searching for high activity,stability,and selectivity catalysts and ascertaining the catalytic mechanism with complete insight.Here,a series of graphene-based N-bridged dual-atom catalysts(M1-N-M2/NC)are systematically investigated via first-principle calculation and a high-throughput screening strategy.The result unveils that N_(2) adsorption on M1-N-M2/NC in bridge-on adsorption mode can effectively break the scaling relationship on single-atom catalysts(SACs).Moreover,V-N-Ru/NC and V-N-Os/NC are systematically screened out as promising e-NRR catalysts,with extremely low limiting potentials of-0.20 and-0.18 V,respectively.Furthermore,the adsorption site competition between*N_(2) and*H,as well as the competitive twin reactions of hydrogen evolution reaction(HER)on intermediates(N_(n)H_(m))during the e-NRR process,is systematically evaluated to form a remodeling insight for the reactions in mechanism,and the e-NRR of new proposed dual-atom catalysts(DACs)is strategically optimized for its high-efficiency performance potential via our remolding insight in e-NRR mechanism.This work provides new ideas and insights for the design and mechanism of e-NRR catalysts and an effective strategy for rapidly screening highly efficient e-NRR catalysts.

关键词： nitrogen reduction dual-atom catalysts high-throughput screening hydrogen evolution reaction density functional theory calculations

nitrogen reduction to Ammonia by a Phosphorus-nitrogen PN^(3) P-Mo(V)Nitride Complex:Significant Enhancement via Ligand Postmodification

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CCS Chemistry 2023年第3期5卷 616-623页

作者： Delong Han Priyanka Chakraborty Mei-Hui Huang Li Yang Hao Huang Théo P.Gonçalves Abdul Hamid Emwas Zhiping Lai Jr-Hau He Aleksander Shkurenko Mohamed Eddaoudi Kuo-Wei Huang Division of Physical Science and Engineering King Abdullah University of Science and TechnologyThuwal 23955 KAUST Catalysis Center King Abdullah University of Science and TechnologyThuwal 23955 Core Lab King Abdullah University of Science and TechnologyThuwal 23955 Advanced Membranes and Porous Materials Research Center King Abdullah University of Science and TechnologyThuwal 23955 Department of Materials Science and Engineering City University of Hong KongKowloon 999077 Agency for Science Technologyand ResearchInstitute of Materials Research and Engineering and Institute of Sustainability for ChemicalsEnergy and EnvironmentSingapore 138634

Efforts to develop organometallic complexes for catalytic nitrogen reduction have seen significant progress in recent years.However,the strategies for improving the activity of the homogenous catalysts have mainly focused on alternating ligands and metals.Herein,we report that the activity and stability of a PN_(P-Mo pincer complex(2)toward dinitrogen(N_(2))reduction were greatly enhanced through postmodification of the PN^(3)P pincer framework of its parent complex(1).A high ratio of NH_(3)/Mo(3525)was achieved in the presence of SmI_(2)as a reductant.In sharp contrast,1 only afforded an NH_(3)/Mo ratio of 21.Moreover,when supported by an anionic pincer ligand,2 furnished a high oxidation state Mo(V)-nitride complex via N_(2)cleavage as a plausible key intermediate in the catalytic process,suggesting a catalytic cycle that may involve different oxidation states(Ⅱ/Ⅴ)from those with 10-πelectron configuration in the literature.

关键词： molybdenum PN^(3)P samarium(Ⅱ)iodide nitrogen reduction ligand postmodification

Computational study of transition metal single-atom catalysts supported on nitrogenated carbon nanotubes for electrocatalytic nitrogen reduction

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Nano Research 2023年第1期16卷 325-333页

作者： Yanyang Qin Yan Li Wenshan Zhao Shenghua Chen Tiantian Wu Yaqiong Su School of Chemistry Xi'an Key Laboratory of Sustainable Energy Materials ChemistryState Key Laboratory of Electrical Insulation and Power EquipmentXi'an Jiaotong UniversityXi'an 710049China Department of Chemistry Tsinghua UniversityBeijing 100084China

Developing efficient and stable catalysts for the electrocatalytic N_(2)reduction reaction(NRR)shows promise in nitrogen fixation.Here,we proposed active and stable single-atom catalysts(SACs)toward NRR,where transition metals are anchored on nitrogenated carbon nanotubes(NCNTs).Among the screened nine common transition metals(Ti,V,Cr,Mn,Fe,Mo,Ru,Rh,and Ag)on(4,4)NCNTs,we found Mo-NCNT possesses the most excellent NRR catalytic activity and selectivity with a low overpotential of 0.29 V.Then,the NRR performance of Mo-NCNT was further engineered by controlling the nanotube diameter,where the lowest overpotential is 0.18 V at a diameter of 9.6Å.In addition,we found a linear scaling relation between*NNH and*NH_(2)on the studied catalysts with the exception of(2,2)and(3,3)Mo-NCNTs,owing to their extremely unstable structures.We attribute the outstanding NRR performance of Mo-NCNT to the moderate adsorption of N_(2)due to the slightly low d-band center of Mo,and the charge donating and accepting capacity of NCNTs.This work has provided a deeper insight into designing highefficiency and stable NRR SACs supported by NCNTs.

关键词： nitrogen reduction single-atom catalysts density functional theory(DFT) carbon nanotubes nitrogen doping

Small moleculeπ-conjugated electron acceptor for highly enhanced photocatalytic nitrogen reduction of BiOBr

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Journal of Materials Science & Technology 2022年第14期109卷 276-281页

作者： Derek Hao Tianyi Ma Baohua Jia Yunxia Wei Xiaojuan Bai Wei Wei Bing-Jie Ni Centre for Technology in Water and Wastewater(CTWW) School of Civil and Environmental EngineeringUniversity of Technology Sydney(UTS)SydneyNSW 2007Australia Centre for Translational Atomaterials Faculty of ScienceEngineering and TechnologySwinburne University of TechnologyHawthornVIC 3122Australia College of Chemistry and Chemical Engineering Lanzhou City UniversityLanzhou 730070China Beijing Engineering Research Center of Sustainable Urban Sewage System Construction and Risk Control Beijing University of Civil Engineering and ArchitectureBeijing 102612China

Artificial ammonia synthesis using solar energy is of great significance as it can help narrow the gap to the zero-net emission target.However,the current photocatalytic activity is generally too low for mass production.Herein,we report a novel bismuth bromide oxide(BiOBr)-Tetracyanoquinodimethane(TCNQ)photocatalyst prepared via a facile self-assembly method.Due to the well-match band structure of TCNQ and Bi OBr,the separation and transfer of photogenerated electron-hole pairs were significantly boosted.More importantly,the abundant delocalizedπelectrons of TCNQ,and the electron-withdrawing property of TNCQ made electrons efficiently accumulated on the catalysts,which can strengthen the adsorption and cleavage of nitrogen molecules.As a result,the photocatalytic activity increased significantly.The highest ammonia yield of the optimized sample reached 2.617 mg/(h gcat),which was 5.6-fold as that of pristine BiOBr and higher than the reported BiOBr-based photocatalysts.The isotope labeled^(15)N_(2)was used to confirm that the ammonia is formed form the fixation of N_(2).Meanwhile,the sample also had good stability.After 4-time usage,the photocatalysts still had about 81.8%as the fresh sample.The results of this work provide a new way for optimizing the electronic structure of photocatalysts to achieve highly efficient photochemical N_(2) reduction.

关键词： BiOBr TCNQ nitrogen reduction Electron accepter Photocatalysis。

Photocatalytic nitrogen reduction to ammonia:Insights into the role of defect engineering in photocatalysts

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Nano Research 2022年第4期15卷 2773-2809页

作者： Huidong Shen Mengmeng Yang Leiduan Hao Jinrui Wang Jennifer Strunk Zhenyu Sun State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Leibniz Institute for Catalysis at the University of Rostock Rostock 18059Germany

Engineering of defects in semiconductors provides an effective protocol for improving photocatalytic N_(2) conversion efficiency.This review focuses on the state-of-the-art progress in defect engineering of photocatalysts for the N_(2) reduction toward ammonia.The basic principles and mechanisms of thermal catalyzed and photon-induced N_(2) reduction are first concisely recapped,including relevant properties of the N_(2) molecule,reaction pathways,and NH3 quantification methods.Subsequently,defect classification,synthesis strategies,and identification techniques are compendiously summarized.Advances of in situ characterization techniques for monitoring defect state during the N_(2) reduction process are also described.Especially,various surface defect strategies and their critical roles in improving the N_(2) photoreduction performance are highlighted,including surface vacancies(i.e.,anionic vacancies and cationic vacancies),heteroatom doping(i.e.,metal element doping and nonmetal element doping),and atomically defined surface sites.Finally,future opportunities and challenges as well as perspectives on further development of defect-engineered photocatalysts for the nitrogen reduction to ammonia are presented.It is expected that this review can provide a profound guidance for more specialized design of defect-engineered catalysts with high activity and stability for nitrogen photochemical fixation.

关键词： photocatalysis nitrogen reduction ammonia synthesis defect engineering

Defect and interface engineering for electrochemical nitrogen reduction reaction under ambient conditions

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Journal of Energy Chemistry 2022年第2期31卷 448-468页

作者： Dongxue Guo Shuo Wang Jun Xu Wenjun Zheng Danhong Wang TKL of Metal and Molecule Based Material Chemistry School of Materials Science and EngineeringCollege of ChemistryNankai UniversityTianjin 300350China Center for Rare Earth and Inorganic Functional Materials Tianjin Key Lab for Rare Earth Materials and ApplicationsNational Institute for Advanced MaterialsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China

Electrochemical nitrogen reduction reaction(e-NRR)under ambient conditions is an emerging strategy to tackle the hydrogen-and energy-intensive operations for traditional Haber-Bosch process in industrial ammonia(NH_(3))synthesis.However,the e-NRR performance is currently impeded by the inherent inertness of N_(2) molecules,the extremely slow kinetics and the overwhelming competition from the hydrogen evolution reaction(HER),all of which cause unsatisfied yield and ammonia selectivity(Faradaic efficiency,FE).Defect and interface engineering are capable of achieving novel physical and chemical properties as well as superior synergistic effects for various electrocatalysts.In this review,we first provide a general introduction to the NRR mechanism.We then focus on the recent progress in defect and interface engineering and summarize how defect and interface can be rationally designed and functioned in NRR catalysts.Particularly,the origin of superior NRR catalytic activity by applying these approaches was discussed from both theoretical and experimental perspectives.Finally,the remaining challenges and future perspectives in this emerging area are highlighted.It is expected that this review will shed some light on designing NRR electrocatalysts with excellent activity,selectivity and stability.

关键词： nitrogen reduction Electrocatalysis Defect engineering Interface engineering Ambient conditions

Pt/TiO_(2–x) nanofibrous aerogel for effective nitrogen reduction: A simple strategy for simultaneous Pt formation and TiO_(2–x) vacancy engineering

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Chinese Chemical Letters 2022年第2期33卷 1001-1005页

作者： Meng Zhang Jin Dai Shengmei Huang Dan Fang Yitao Liu Jianyong Yu Bin Ding Andreas Greiner Innovation Center for Textile Science and Technology College of TextilesDonghua UniversityShanghai 201620China Macromolecular Chemistry and Bavarian Polymer Institute University of BayreuthBayreuth 95440Germany

Electrocatalysis plays an increasingly important role in converting atmospheric molecules(e.g.,N_(2),CO_(2) and H_(2)O)to value-added products(e.g.,NH_(3),C_(2)H_(4)and H_(2)).However,developing a simple strategy for preparing catalysts with high performance for the effective conversion of clean energy is still full of chal-lenges.Herein,we describe a straightforward,one-step reduction method to achieve the formation of Pt nanoparticles(NPs)and the vacancy engineering of TiO_(2-x)nanofibers(NFs)simultaneously,which can be accomplished in 5 min.Furthermore,a Pt/TiO_(2-x)nanofibrous aerogel(NA)with an ordered cellular archi-tecture is prepared through a directional freezing technology.The Pt/TiO_(2-x)NA with excellent mechanical properties can be made into a self-supporting electrode for electrocatalytic N_(2)reduction reaction(NRR),showing high NH_(3) yield rate(4.81×10^(-10)mol/s cm^(-2))and Faraday efficiency(14.9%)at-0.35 V vs.RHE.

关键词： Vacancy engineering Pt nanoparticles TiO_(2–x)nanofibers Nanofibrous aerogel Electrocatalysis nitrogen reduction

Water flooding behavior in flow cells for ammonia production via electrocatalytic nitrogen reduction

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Fundamental Research 2022年第5期2卷 757-763页

作者： Zhefei Pan Farhan Khalid Abdullah Tahir Oladapo Christopher Esan Jie Zhu Rong Chen Liang An Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARChina Key Laboratory of Low-grade Energy Utilization Technologies and Systems(Chongqing University) Ministry of EducationChongqing 400030China Institute of Engineering Thermophysics Chongqing UniversityChongqing 400030China

The green production of ammonia,in an electrochemical flow cell under ambient conditions,is a promising way to replace the energy-intensive Haber-Bosch process.In the operation of this flow cell with an alkaline electrolyte,water is produced at the anode but also required as an essential reactant at the cathode for nitrogen reduction.Hence,water from the anode is expected to diffuse through the membrane to the cathode to compensate for the water needed for nitrogen reduction.Excessive water permeation,however,tends to increase the possibility of water flooding,which would not only create a large barrier for nitrogen delivery and availability,but also lead to severe hydrogen evolution as side reaction,and thus significantly lower the ammonia production rate and Faradaic efficiency.In this work,the water flooding phenomenon in flow cells for ammonia production via electrocatalytic nitrogen reduction is verified via the visualization approach and the electrochemical cell performance.In addition,the effects of the nitrogen flow rate,applied current density,and membrane thickness on the water crossover flux and ammonia production rate are comprehensively studied.The underlying mechanism of water transport through the membrane,including diffusion and electro-osmotic drag,is precisely examined and specified to provide more insight on water flooding behavior in the flow cell.

关键词： nitrogen reduction Electrochemical ammonia production Flow cells Water flooding Water transport Operation conditions

Folic Acid Self-Assembly Enabling Manganese Single-Atom Electrocatalyst for Selective nitrogen reduction to Ammonia

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Nano-Micro Letters 2021年第8期13卷 163-174页

作者： Xuewan Wang Dan Wu Suyun Liu Jiujun Zhang Xian-Zhu Fu Jing-Li Luo Shenzhen Key Laboratory of Polymer Science and Technology Guangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Institute for Sustainable Energy College of SciencesShanghai UniversityShanghai 200444People’s Republic of China

Efficient and robust single-atom catalysts(SACs)based on cheap and earth-abundant elements are highly desirable for electrochemical reduction of nitrogen to ammonia(NRR)under ambient conditions.Herein,for the first time,a Mn-N-C SAC consisting of isolated manganese atomic sites on ultrathin carbon nanosheets is developed via a template-free folic acid self-assembly strategy.The spontaneous molecular partial dissociation enables a facile fabrication process without being plagued by metal atom aggregation.Thanks to well-exposed atomic Mn active sites anchored on two-dimensional conductive carbon matrix,the catalyst exhibits excellent activity for NRR with high activity and selectivity,achieving a high Faradaic efficiency of 32.02%for ammonia synthesis at−0.45 V versus reversible hydrogen electrode.Density functional theory calculations unveil the crucial role of atomic Mn sites in promoting N_(2) adsorption,activation and selective reduction to NH_(3) by the distal mechanism.This work provides a simple synthesis process for Mn-N-C SAC and a good platform for understanding the structure-activity relationship of atomic Mn sites.

关键词： Folic acid self-assembly N-doped carbon sheet Manganese single-atom catalyst Electrocatalysis nitrogen reduction

Rich B active centers in Penta-B_(2)C as high-performance photocatalyst for nitrogen reduction

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Chinese Chemical Letters 2021年第12期32卷 3821-3824页

作者： Ran Wang Chaozheng He Weixing Chen Chenxu Zhao Jinrong Huo Institute of Environmental and Energy Catalysis School of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China Shaanxi Key Laboratory of Optoelectronic Functional Materials and Devices School of Materials Science and Chemical EngineeringXi'an Technological UniversityXi'an 710021China School of Sciences Xi'an Technological UniversityXi'an 710021China

The photocatalytic nitrogen reduction reaction(NRR) has mild reaction conditions and only requires sunlight energy as a driving force to replace the traditional ammonia synthesis method. We herein investigate the catalytic activity and selectivity on Penta-B_(2)C for NRR by using density functional theory calculations. Penta-B_(2)C is a semiconductor with an indirect bandgap(2.328 e V) and is kinetically stable based on molecular dynamic simulations. The optical absorption spectrum of Penta-B;C is achieved in the ultraviolet and visible range. Effective light absorption is more conducive to generate photo-excited electrons and improving photocatalytic performances. Rich B atoms as activation sites in Penta-B_(2)C facilitate capturing N_(2). The activated N_(2)molecule prefers the side-on adsorption configuration on Penta-B_(2)C, which facilitates the subsequent reduction reaction. Among considered NRR mechanisms on Penta-B_(2)C, the best pathway prefers the enzymatic mechanism, only required a low onset potential of 0.23 V. The hydrogen evolution reaction is inhibited when the hydrogen adsorption concentration is increased or N_(2)molecules first occupy the adsorption sites. Our results indicate Penta-B_(2)C is a highly reactive and selective photocatalyst for NRR. Our work provides theoretical insights into the experiments and has guiding significance to synthesize efficient NRR photocatalysts.

关键词： nitrogen reduction Photocatalytic Penta-B_(2)C Mechanism B active center