NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic s...NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic structures,particularly the d-electron density of metal sites,which impede water dissociation and lead to poor hydrogen adsorption/desorption capabilities.Herein,we introduce an efficient cooperative d-electron density regulation(CDDR)engineering to comprehensively optimize the delectron density of NiFe LDH by grafting MoO_(x) -modified NiFe LDH nanosheets onto porous nickel particles(PNPs).The PNPs facilitate d-electron density modulation along the edges of the nanosheets,while the MoO_(x) species enable d-electron density modulation across the plane of the nanosheets,thus cooperatively constructing enriched d-electron density in NiFe LDH.Theoretical studies validate the CDDR process and reveal that the enriched d-electron density accelerates water dissociation and optimizes the hydrogen adsorption behavior of NiFe LDH.As a result,the engineered catalyst exhibits significantly improved HER activity,achieving an ultra-low overpotential of 38 mV at 10 mA cm^(-2)in 1 M KOH.Additionally,the CDDR-optimized catalyst also exhibits good OER performance,demonstrating excellent bifunctional performance for overall water splitting in both alkaline freshwater and seawater electrolytes.This work presents a novel CDDR strategy for engineering NiFe LDH into efficient HER catalysts without compromising its OER activity,potentially paving the way for the development of active and robust electrocatalysts for sustainable energy applications.展开更多
A new kind offl biomedical titanium alloy, Ti-35Nb-4Sn-6Mo-9Zr, composed of non-toxic elements Nb, Mo, Zr and Sn with lower elastic modulus and higher strength was designed based on d-electron alloy design theory and ...A new kind offl biomedical titanium alloy, Ti-35Nb-4Sn-6Mo-9Zr, composed of non-toxic elements Nb, Mo, Zr and Sn with lower elastic modulus and higher strength was designed based on d-electron alloy design theory and JMatPro software using orthogonal experiment. The microstructure and basic mechanical properties of designed alloy were investigated. The results show that the alloy is composed of single fl equiaxed grains after solution treatment at 800 ~C. Compared with Ti-6A1-4V, the mechanical properties of the designed alloy are more excellent： E=65 GPa, σb=834 MPa, σ0.2=802 MPa, and σ=11%, which is expected to become a promising new type implanted material. The research approach adopted can reduce the experimental time and cost effectively, and get the ideal experimental results.展开更多
The coordination-dependent force fleld of TersofF for covalently bonded Si has been used tocalculate the cleavage force as a function of interplanar separation and hence to estimate surfaceenergies. This force field i...The coordination-dependent force fleld of TersofF for covalently bonded Si has been used tocalculate the cleavage force as a function of interplanar separation and hence to estimate surfaceenergies. This force field is already fitted to density functional results. The relation to bond-breaking and electron correlation will be emphasized. Finnis-Sinclair-type many-body potentialshave then been used to treat some d-electron metals. In particular, results for cleavage forcein bcc Fe will be presented, and also some calculations as two perfectly planar Fe surfaces arerubbed together' at different interplanar separations. Finally, lattice dynamical models for thesteady-state propagation of a screw dislocation, and then of a crack, will be used, again within abond-breaking type of force field. For the screw dislocation propagation. a solitary wave equationis shown to follow in the 'almost continuum' limit. Energy radiated by phonons as the dislocationmoves can thereby be calculated.展开更多
Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)to high-value-added products is a crucial approach for promoting carbon recycling and mitigating energy challenges.Here,extensive theoretical screenings were conduct...Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)to high-value-added products is a crucial approach for promoting carbon recycling and mitigating energy challenges.Here,extensive theoretical screenings were conducted on the nitrogen-doped graphene-supported heteronuclear dual-atom catalysts(DACs)M_(1)/M_(2)-NC(M=V,Cr,Mn,Fe,Co,Ni,and Cu)for CO_(2)RR using density functional theory(DFT)calculations.The calculations indicate that Mn/Cu-NC exhibits superior catalytic activity and selectivity for the CO_(2)RR to HCOOH with a limiting potential as low as−0.15 V.The superior performance is attributed to the strong d-electron coupling between Mn and Cu dual atoms in Mn/Cu-NC,which results in an upward shift of the d-band center of the Mn single atom closer to the Fermi level.Moreover,the adsorption of the key intermediate*OCHO on the Mn single atom was further enhanced,thereby reducing the limiting potential and improving the catalytic performance for CO_(2)RR.This work offers a comprehensive theoretical insight into the catalytic mechanism of the novel Mn/Cu-NC DAC for CO_(2)RR and establishes a critical descriptor of d-band center of the catalytic active center to determine the catalytic activity of DACs for CO_(2)RR,thereby providing guidance for the future design and fabrication of graphene-based metal DACs for CO_(2)RR.展开更多
基金financially supported from the National Key Research and Development Program of China(2022YFB3803600)the National Natural Science Foundation of China(52301272,22309168,12564025,and 52472205)+7 种基金the Fundamental Research Funds for the Central Universities(CCNU25ZH006)the National College Student Innovation and Entrepreneurship Training Project(202510513082)the Research Program of HBNU(2025X082 and2025Y145)the Foundation of Hubei Key Laboratory of Photoelectric Materials and Devices(PMD202404)the General Program of Open Project of the State Key Laboratory of Precision Welding and Joining of Materials Structures(MSWJ-25M-18)the Key Research Project of Hubei Provincial Department of Education(No.D20252503)the Key Project of Hubei Provincial Natural Science Foundation of China(2025AFD002)the Foundation of National Laboratory of Solid State Microstructures(M37087)。
文摘NiFe layered double hydroxide(NiFe LDH)has emerged as a promising catalyst for the oxygen evolution reaction(OER);however,its hydrogen evolution reaction(HER)activity remains suboptimal due to unfavorable electronic structures,particularly the d-electron density of metal sites,which impede water dissociation and lead to poor hydrogen adsorption/desorption capabilities.Herein,we introduce an efficient cooperative d-electron density regulation(CDDR)engineering to comprehensively optimize the delectron density of NiFe LDH by grafting MoO_(x) -modified NiFe LDH nanosheets onto porous nickel particles(PNPs).The PNPs facilitate d-electron density modulation along the edges of the nanosheets,while the MoO_(x) species enable d-electron density modulation across the plane of the nanosheets,thus cooperatively constructing enriched d-electron density in NiFe LDH.Theoretical studies validate the CDDR process and reveal that the enriched d-electron density accelerates water dissociation and optimizes the hydrogen adsorption behavior of NiFe LDH.As a result,the engineered catalyst exhibits significantly improved HER activity,achieving an ultra-low overpotential of 38 mV at 10 mA cm^(-2)in 1 M KOH.Additionally,the CDDR-optimized catalyst also exhibits good OER performance,demonstrating excellent bifunctional performance for overall water splitting in both alkaline freshwater and seawater electrolytes.This work presents a novel CDDR strategy for engineering NiFe LDH into efficient HER catalysts without compromising its OER activity,potentially paving the way for the development of active and robust electrocatalysts for sustainable energy applications.
基金Project(BE2011778)supported by Science and Technology Support Program of Jiangsu Province,ChinaProject(20133069014)supported by Aeronautical Science Foundation of China
文摘A new kind offl biomedical titanium alloy, Ti-35Nb-4Sn-6Mo-9Zr, composed of non-toxic elements Nb, Mo, Zr and Sn with lower elastic modulus and higher strength was designed based on d-electron alloy design theory and JMatPro software using orthogonal experiment. The microstructure and basic mechanical properties of designed alloy were investigated. The results show that the alloy is composed of single fl equiaxed grains after solution treatment at 800 ~C. Compared with Ti-6A1-4V, the mechanical properties of the designed alloy are more excellent： E=65 GPa, σb=834 MPa, σ0.2=802 MPa, and σ=11%, which is expected to become a promising new type implanted material. The research approach adopted can reduce the experimental time and cost effectively, and get the ideal experimental results.
文摘The coordination-dependent force fleld of TersofF for covalently bonded Si has been used tocalculate the cleavage force as a function of interplanar separation and hence to estimate surfaceenergies. This force field is already fitted to density functional results. The relation to bond-breaking and electron correlation will be emphasized. Finnis-Sinclair-type many-body potentialshave then been used to treat some d-electron metals. In particular, results for cleavage forcein bcc Fe will be presented, and also some calculations as two perfectly planar Fe surfaces arerubbed together' at different interplanar separations. Finally, lattice dynamical models for thesteady-state propagation of a screw dislocation, and then of a crack, will be used, again within abond-breaking type of force field. For the screw dislocation propagation. a solitary wave equationis shown to follow in the 'almost continuum' limit. Energy radiated by phonons as the dislocationmoves can thereby be calculated.
基金supported by the National Key R&D Project(2022YFA1503900)the National Natural Science Foundation of China(22363001,22479032 and 22250710677)+1 种基金the NSFC Center for SingleAtom Catalysis(22388102)the Natural Science Special Foundation of Guizhou University(202140)。
文摘Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)to high-value-added products is a crucial approach for promoting carbon recycling and mitigating energy challenges.Here,extensive theoretical screenings were conducted on the nitrogen-doped graphene-supported heteronuclear dual-atom catalysts(DACs)M_(1)/M_(2)-NC(M=V,Cr,Mn,Fe,Co,Ni,and Cu)for CO_(2)RR using density functional theory(DFT)calculations.The calculations indicate that Mn/Cu-NC exhibits superior catalytic activity and selectivity for the CO_(2)RR to HCOOH with a limiting potential as low as−0.15 V.The superior performance is attributed to the strong d-electron coupling between Mn and Cu dual atoms in Mn/Cu-NC,which results in an upward shift of the d-band center of the Mn single atom closer to the Fermi level.Moreover,the adsorption of the key intermediate*OCHO on the Mn single atom was further enhanced,thereby reducing the limiting potential and improving the catalytic performance for CO_(2)RR.This work offers a comprehensive theoretical insight into the catalytic mechanism of the novel Mn/Cu-NC DAC for CO_(2)RR and establishes a critical descriptor of d-band center of the catalytic active center to determine the catalytic activity of DACs for CO_(2)RR,thereby providing guidance for the future design and fabrication of graphene-based metal DACs for CO_(2)RR.
