Based on the reported Fe clusters constructed by using N-tris(hydroxymethyl)methylglycine (H_5thmmg),herein,we explored the use of H_5 thmmg for Ni chemistry.Successfully,an octanuclear Ni cluster,Ni_(8)O(H_(3)thmmg)_...Based on the reported Fe clusters constructed by using N-tris(hydroxymethyl)methylglycine (H_5thmmg),herein,we explored the use of H_5 thmmg for Ni chemistry.Successfully,an octanuclear Ni cluster,Ni_(8)O(H_(3)thmmg)_6·2NO_(3)(Ni_(8)) was acquired under solvothermal condition.Its metallic core is comprised of two centrosymmetric cubanes Ni_(4)(μ_(3)-O)_(3)(μ_6-O) linked by sharing an O^(2-)ion and six H_(3)thmmg^(2-) ligands are attached to the periphery.Interestingly,the 2-mercapto-5-amino-1,3,4-thiadiazole (Hmat) ligand with both N and S donor atoms was introduced into the synthesis of Ni_(8) cluster,a disparate decanuclear nickel cluster,Ni_(10)O(OH)_(2)(H_(3)thmmg)_(4)(mat)_(8)(Ni_(10)) is assembled by H_(3)thmmg^(2-) and mat^(-) mixed ligands.The metal core of Ni_(10)cluster is a pudgy tetrahedron,whose four vertexes are four Ni^(2+)ions and the remanent six Ni^(2+) ions are located in the tetrahedral cavity.Four H_(3)thmmg^(2-) ligands are located at the four vertices of the tetrahedron and 8 mat^(-) ligands are all on the six sides of the tetrahedron.The different synthetic conditions contribute to the different configurations.Magnetic studies indicate that both complexes Ni_(8) and Ni_(10) display antiferromagnetic interactions.展开更多
Single-atom catalysts(SACs)have attracted increasing concerns in electrocatalysis because of their maximal metal atom utilization,distinctive electronic properties,and catalytic performance.However,the isolated single...Single-atom catalysts(SACs)have attracted increasing concerns in electrocatalysis because of their maximal metal atom utilization,distinctive electronic properties,and catalytic performance.However,the isolated single sites are disadvantageous for reactions that require simultaneously activating different reactants/intermediates.Fully exposed metal cluster catalyst(FECC),inheriting the merits of SACs and metallic nanoparticles,can synergistically adsorb and activate reactants/intermediates on their multi-atomic sites,demonstrating great promise in electrocatalytic reactions.Here a facile method to regulate the atomic dispersion of Ni species from cluster to single-atom scale for efficient CO_(2) reduction was developed.The obtained Ni FECC exhibits high Faradaic efficiency of CO up to 99%,high CO partial current density of 347.2 mA cm^(−2),and robust durability under 20 h electrolysis.Theoretical calculations illuminate that the ensemble of multiple Ni atoms regulated by sulfur atoms accelerates the reaction kinetics and thus improves CO production.展开更多
The possible geometrical and the electronic structures of small MgnNi （n = 1 - 7） clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron af...The possible geometrical and the electronic structures of small MgnNi （n = 1 - 7） clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron affinity, the dissociation energy and the second difference in energy are calculated and discussed. The properties of MgnNi clusters are also discussed when the number of Mg atom increases.展开更多
Two-dimensional metal dichalcogenides have been evidenced as potential electrocatalysts for hydrogen evolution reaction(HER);however,their application is limited by a poor oxygen evolution reaction(OER)activity due to...Two-dimensional metal dichalcogenides have been evidenced as potential electrocatalysts for hydrogen evolution reaction(HER);however,their application is limited by a poor oxygen evolution reaction(OER)activity due to insufficient number/types of multi-integrated active sites.In this study,we report a novel bifunctional catalyst developed by simultaneous engineering of single nickel atoms(Ni_(SA)) and nickel phosphate clusters(Ni_(Pi)) to synergistically trigger surface-functionalized MoS_(2) nanosheets(NSs)resulting in high reactivities for both HER and OER.The Ni_(SA)-Ni_(Pi)/MoS_(2)NSs material exhibits a fairly Pt-like HER behavior with an overpotential of 94.0 mV and a small OER overpotential of 314.0 mV to reach 10 mA cm^(-2) in freshwater containing 1.0 M KOH.Experimental results of the catalyst are well supported by theoretical study,which reveals the significant modulation of electronic structure and enrichment of electroactive site number/types with their reasonably adjusted free adsorption energy.For evaluating practicability,the Ni_(SA)-Ni_(Pi)/MoS_(2)NSs-based electrolyzer delivers effective operation voltage of 1.62,1.52,and 1.66 V at 10 mA cm^(-2) and superior long-term stability as compared to Pt/C//RuO_(2) system in freshwater,mimic seawater,and natural seawater,respectively.The present study indicates that the catalyst is a promising candidate for the practical production of green hydrogen via water electrolysis.展开更多
The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functiona...The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functional theory（DFT） calculations.Structural candidates obtained from our GA search were further optimized with first-principles calculations.Four typical isomers of lower-energy neutral Nin（n=31―35） clusters were shown,as well as their binding energies per atom（Eb）,second differences in energy and magnetic moment.The medium-sized nickel clusters in a size range from 31 atoms to 35 atoms were found to favor the distorted double-icosahedron-like structures.The fragments composed of the central atoms appear as some small stable clusters.展开更多
As a transition material between bulk materials and individual atoms,nickel clusters have interesting electrical and structural characteristics that could make them useful as catalysts.To examine the catalytic efficie...As a transition material between bulk materials and individual atoms,nickel clusters have interesting electrical and structural characteristics that could make them useful as catalysts.To examine the catalytic efficiency of nickel clusters in different applications,this Review combines experimental techniques with density functional theory(DFT).Researchers have shown that nickel clusters can activate and alter tiny molecules like CO,NO,and H_(2)through DFT studies that delve deeply into their electronic structures,adsorption mechanisms,and stability.These findings lay the groundwork for the development of effective catalysts for various processes.Nickel clusters considerably improve the hydrogen evolution reaction(HER),indicating their promise for renewable energy conversion.Furthermore,electrocatalysis for the oxygen evolution reaction(OER)showcases the electrochemical performance of nickel clusters,demonstrating their stability and efficiency.The adaptability of nickel clusters is further demonstrated by their use in nitrogen reduction to ammonia.Experimental data confirm that these clusters are good catalysts for this crucial industrial activity.Hydrocarbon reforming and pollutant degradation are two areas in which research has shown that nickel clusters can be useful in thermal reactions.X-ray absorption spectroscopy(XAS)and environmental transmission electron microscopy(ETEM)are examples of in situ characterization techniques that support theoretical predictions by providing real-time insights into the structural alterations and active sites of nickel clusters during these processes.Preparing the way for future research and practical applications in energy and environmental technologies,this thorough study highlights the great potential of nickel clusters in constructing sustainable and efficient catalytic systems.展开更多
The double crown hexakis[(di-μ-benzylthio)nickel]cluster,[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH,was obtained by reacting C_(6)H_(5)CH_(2)SNa with[(CH_(3))_(2)CHOCS_(2)]_(2)Ni in EtOH.The results of electr...The double crown hexakis[(di-μ-benzylthio)nickel]cluster,[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH,was obtained by reacting C_(6)H_(5)CH_(2)SNa with[(CH_(3))_(2)CHOCS_(2)]_(2)Ni in EtOH.The results of electrochemical studies show that[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]is a quasi-reversible process.The crystal structure of[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH is composed of discrete[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]and C_(2)H_(5)OH solvent molecules.Each Ni atom is surrounded by four S atoms of theµ2-SCH_(2)C_(6)H_(5)ligands in a distorted square-planar structure.The C_(6)H_(5)CH_(2)S-side chains are arranged in the axial and equatorial positions,alternately,concerning the pseudo-hexagonal axis of the molecule.Strongπ-πand C-H···πeffects form the supramolecular nano-channel along the a-axis in the crystal,which wraps the solvent ethanol molecules in it.In addition,a wall is formed along the b-and c-axes,so that the ethanol molecules can freely enter and leave along the a-axis.These effects result in the ability of the title compound to adsorb and desorb ethanol molecules.Thermogravimetric analysis and powder X-ray diffraction at different temperature are provided to demonstrate this point.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.22101148,22071126)the Natural Science Foundation of Shandong Province(No.ZR2021QB008)。
文摘Based on the reported Fe clusters constructed by using N-tris(hydroxymethyl)methylglycine (H_5thmmg),herein,we explored the use of H_5 thmmg for Ni chemistry.Successfully,an octanuclear Ni cluster,Ni_(8)O(H_(3)thmmg)_6·2NO_(3)(Ni_(8)) was acquired under solvothermal condition.Its metallic core is comprised of two centrosymmetric cubanes Ni_(4)(μ_(3)-O)_(3)(μ_6-O) linked by sharing an O^(2-)ion and six H_(3)thmmg^(2-) ligands are attached to the periphery.Interestingly,the 2-mercapto-5-amino-1,3,4-thiadiazole (Hmat) ligand with both N and S donor atoms was introduced into the synthesis of Ni_(8) cluster,a disparate decanuclear nickel cluster,Ni_(10)O(OH)_(2)(H_(3)thmmg)_(4)(mat)_(8)(Ni_(10)) is assembled by H_(3)thmmg^(2-) and mat^(-) mixed ligands.The metal core of Ni_(10)cluster is a pudgy tetrahedron,whose four vertexes are four Ni^(2+)ions and the remanent six Ni^(2+) ions are located in the tetrahedral cavity.Four H_(3)thmmg^(2-) ligands are located at the four vertices of the tetrahedron and 8 mat^(-) ligands are all on the six sides of the tetrahedron.The different synthetic conditions contribute to the different configurations.Magnetic studies indicate that both complexes Ni_(8) and Ni_(10) display antiferromagnetic interactions.
基金funding from the Alexander von Humboldt Foundation(Germany)supported by the National Key R&D Program of China(2020YFB1505603)+2 种基金the National Natural Science Foundation of China(51925102)Key Research Program of the Chinese Academy of Sciences(ZDRW-CN-2021-3)Youth Innovation Promotion Association CAS(E1202002)。
文摘Single-atom catalysts(SACs)have attracted increasing concerns in electrocatalysis because of their maximal metal atom utilization,distinctive electronic properties,and catalytic performance.However,the isolated single sites are disadvantageous for reactions that require simultaneously activating different reactants/intermediates.Fully exposed metal cluster catalyst(FECC),inheriting the merits of SACs and metallic nanoparticles,can synergistically adsorb and activate reactants/intermediates on their multi-atomic sites,demonstrating great promise in electrocatalytic reactions.Here a facile method to regulate the atomic dispersion of Ni species from cluster to single-atom scale for efficient CO_(2) reduction was developed.The obtained Ni FECC exhibits high Faradaic efficiency of CO up to 99%,high CO partial current density of 347.2 mA cm^(−2),and robust durability under 20 h electrolysis.Theoretical calculations illuminate that the ensemble of multiple Ni atoms regulated by sulfur atoms accelerates the reaction kinetics and thus improves CO production.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10676022)
文摘The possible geometrical and the electronic structures of small MgnNi （n = 1 - 7） clusters are optimised by the density functional theory with a LANL2DZ basis set. The binding energy, the energy gap, the electron affinity, the dissociation energy and the second difference in energy are calculated and discussed. The properties of MgnNi clusters are also discussed when the number of Mg atom increases.
基金supported by the Regional Leading Research Center Program(2019R1A5A8080326)Basic Science Research Program(2020R1F1A1075921)BRL Program(2020R1A4A1018259)through the National Research Foundation(NRF)funded by the Ministry of Science and ICT of Republic of Korea.
文摘Two-dimensional metal dichalcogenides have been evidenced as potential electrocatalysts for hydrogen evolution reaction(HER);however,their application is limited by a poor oxygen evolution reaction(OER)activity due to insufficient number/types of multi-integrated active sites.In this study,we report a novel bifunctional catalyst developed by simultaneous engineering of single nickel atoms(Ni_(SA)) and nickel phosphate clusters(Ni_(Pi)) to synergistically trigger surface-functionalized MoS_(2) nanosheets(NSs)resulting in high reactivities for both HER and OER.The Ni_(SA)-Ni_(Pi)/MoS_(2)NSs material exhibits a fairly Pt-like HER behavior with an overpotential of 94.0 mV and a small OER overpotential of 314.0 mV to reach 10 mA cm^(-2) in freshwater containing 1.0 M KOH.Experimental results of the catalyst are well supported by theoretical study,which reveals the significant modulation of electronic structure and enrichment of electroactive site number/types with their reasonably adjusted free adsorption energy.For evaluating practicability,the Ni_(SA)-Ni_(Pi)/MoS_(2)NSs-based electrolyzer delivers effective operation voltage of 1.62,1.52,and 1.66 V at 10 mA cm^(-2) and superior long-term stability as compared to Pt/C//RuO_(2) system in freshwater,mimic seawater,and natural seawater,respectively.The present study indicates that the catalyst is a promising candidate for the practical production of green hydrogen via water electrolysis.
基金Supported by the National Natural Science Foundation of China(Nos.21043001 and 20773047)
文摘The lowest-energy structures and properties of neutral nickel clusters Nin（n=31―35） were studied by a combination method of genetic algorithm（GA） searching with a tight-binding potential and the density functional theory（DFT） calculations.Structural candidates obtained from our GA search were further optimized with first-principles calculations.Four typical isomers of lower-energy neutral Nin（n=31―35） clusters were shown,as well as their binding energies per atom（Eb）,second differences in energy and magnetic moment.The medium-sized nickel clusters in a size range from 31 atoms to 35 atoms were found to favor the distorted double-icosahedron-like structures.The fragments composed of the central atoms appear as some small stable clusters.
基金National Natural Science Foundation of China(22172167)Open fund of State Key Laboratory of Catalysis(DICP,2024SKL-A-006).
文摘As a transition material between bulk materials and individual atoms,nickel clusters have interesting electrical and structural characteristics that could make them useful as catalysts.To examine the catalytic efficiency of nickel clusters in different applications,this Review combines experimental techniques with density functional theory(DFT).Researchers have shown that nickel clusters can activate and alter tiny molecules like CO,NO,and H_(2)through DFT studies that delve deeply into their electronic structures,adsorption mechanisms,and stability.These findings lay the groundwork for the development of effective catalysts for various processes.Nickel clusters considerably improve the hydrogen evolution reaction(HER),indicating their promise for renewable energy conversion.Furthermore,electrocatalysis for the oxygen evolution reaction(OER)showcases the electrochemical performance of nickel clusters,demonstrating their stability and efficiency.The adaptability of nickel clusters is further demonstrated by their use in nitrogen reduction to ammonia.Experimental data confirm that these clusters are good catalysts for this crucial industrial activity.Hydrocarbon reforming and pollutant degradation are two areas in which research has shown that nickel clusters can be useful in thermal reactions.X-ray absorption spectroscopy(XAS)and environmental transmission electron microscopy(ETEM)are examples of in situ characterization techniques that support theoretical predictions by providing real-time insights into the structural alterations and active sites of nickel clusters during these processes.Preparing the way for future research and practical applications in energy and environmental technologies,this thorough study highlights the great potential of nickel clusters in constructing sustainable and efficient catalytic systems.
基金supported by the Research Initiation Fund for Distinguished Professors (13510007) of Henan University of Science and Technology and Luoyang Heluo Talents Plan Fund
文摘The double crown hexakis[(di-μ-benzylthio)nickel]cluster,[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH,was obtained by reacting C_(6)H_(5)CH_(2)SNa with[(CH_(3))_(2)CHOCS_(2)]_(2)Ni in EtOH.The results of electrochemical studies show that[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]is a quasi-reversible process.The crystal structure of[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]·C_(2)H_(5)OH is composed of discrete[Ni_(6)(SCH_(2)C_(6)H_(5))_(12)]and C_(2)H_(5)OH solvent molecules.Each Ni atom is surrounded by four S atoms of theµ2-SCH_(2)C_(6)H_(5)ligands in a distorted square-planar structure.The C_(6)H_(5)CH_(2)S-side chains are arranged in the axial and equatorial positions,alternately,concerning the pseudo-hexagonal axis of the molecule.Strongπ-πand C-H···πeffects form the supramolecular nano-channel along the a-axis in the crystal,which wraps the solvent ethanol molecules in it.In addition,a wall is formed along the b-and c-axes,so that the ethanol molecules can freely enter and leave along the a-axis.These effects result in the ability of the title compound to adsorb and desorb ethanol molecules.Thermogravimetric analysis and powder X-ray diffraction at different temperature are provided to demonstrate this point.
