Chiral topological semimetals hosting multifold fermions and exotic surface states represent a frontier in topological materials research. Among them, noncentrosymmetric cubic B20 compounds—notably transitionmetal si...Chiral topological semimetals hosting multifold fermions and exotic surface states represent a frontier in topological materials research. Among them, noncentrosymmetric cubic B20 compounds—notably transitionmetal silicides and germanides—offer a unique platform for realizing symmetry-protected topological phases and unconventional optoelectronic responses. Here, we report the physical properties of Rh Ge and Co Ge single crystals with B20 structure in detail. Transport measurements revea metallic behavior with characteristic Fermi-liquid scaling at low temperatures, while magnetization results confirm paramagnetism in both compounds. In addition,both materials exhibit low carrier concentrations with small electronic specific heat coefficients, indicating their semimetal feature with weak electronic correlations. Such high-quality Co Ge and Rh Ge single crystals provide a material platform to explore the evolution of multifold fermions and the instability of helicoid-arc surface states with spin–orbit coupling and surface environment in B20 material systems.展开更多
The exploration of cheap,efficient,and durable bifunctional electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is highly desired to push forward the commercialization of rechargeable ...The exploration of cheap,efficient,and durable bifunctional electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is highly desired to push forward the commercialization of rechargeable metal–air batteries.Here,bifunctional ORR/OER electrocatalysts based on CoxP(0<x<2,i.e.,Co_(2)P,Co_(2)P/CoP mixture,and CoP)nanoparticles(NPs)anchored on N,P-doped carbon framework(Co_(x)P@NPC)are developed via one-step carbonization of the mixture of as-synthesized ZIF-67 and melamine–phytic acid supermolecular aggregate(MPSA).The stoichiometric ratio of resultant Co_(x)P NPs can be rationally designed by adjusting the introduced ratio of ZIF-67 to MPSA,enabling their fabrication in a controlled manner.It is found that the as-synthesized Co_(2)P@NPC exhibits the best bifunctional ORR/OER activity among the Co_(x)P@NPC analogues,with a reversible oxygen electrode index(ΔE=E_(j10)−E_(1/2))down to~0.75 V.The constructed Zn–air battery based on Co_(2)P@NPC delivers a peak power density of 157 mW cm^(−2) and an excellent charge-discharge stability with negligible voltage decay for 140 h at 10 mA cm^(−2),superior to those based on Pt/C+RuO_(2) and most Co_(x)P-based electrodes ever reported.展开更多
For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions...For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.展开更多
Four FeCO states with 3d4s and 3d3d electrons spinpaired or spinunpaired were examined to investigate the influences of pairing versus unpairing mechanisms upon the bonding and interaction in FeCO.The calculation resu...Four FeCO states with 3d4s and 3d3d electrons spinpaired or spinunpaired were examined to investigate the influences of pairing versus unpairing mechanisms upon the bonding and interaction in FeCO.The calculation results show that the FeCO bonding and interaction are determined by a balance between the bonding stabilization and the exchange stabilization with 3d4s electron spinpairing or without it.The 3d3d electron spinpairing versus unpairing has a surprised effect on the FeCO bonding properties even though the 3d orbitals are usually considered as non bonding ones.展开更多
A new complex C（18）H（24）CoF6N（12）Si has been synthesized by the reaction of cobalt（II） fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. Thi...A new complex C（18）H（24）CoF6N（12）Si has been synthesized by the reaction of cobalt（II） fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. This complex has been characterized by different techniques such as elemental analysis, IR studies, magnetic measurements, electronic absorption measurements and single-crystal X-ray structure determination. The crystals are hexagonal in the R-3 space group, with a = 13.225（6）, b = 13.225（6）, c = 12.517（11） A, and g = 120°. In complex [Co（im）6]SiF6, the cobalt atom is six-coordinated to adopt a regular octahedral geometry and the SiF62-ion acts as the counter anion. The crystal displays a network structure and SiF62- bridging hexagram formation by N-（39）···F-Si interactions between imdazole and SiF62-. SiF62-plays an important role in assembling the supramolecular aggregates.展开更多
Neutron diffraction studies of the low-temperature relaxor ferroelectric phases of[NH_(4)^(+)]M(HCO_(2))_(3),where M=Mn^(2+)and Zn^(2+),show that a third of the NH_(4)^(+)t cations remain subtly structurally disordere...Neutron diffraction studies of the low-temperature relaxor ferroelectric phases of[NH_(4)^(+)]M(HCO_(2))_(3),where M=Mn^(2+)and Zn^(2+),show that a third of the NH_(4)^(+)t cations remain subtly structurally disordered to low temperature.All NH_(4)^(+) cations within the channels are well separated from each other,with significant hydrogen bonds only with the anionic M(HCO_(2))_(3) framework.Complementary studies of the dynamics using ^(2)H solid state NMR and quasielastic neutron scattering indicate significant rotational motion in both paraelectric and ferroelectric phases,which evolves gradually with increasing temperature with no abrupt change at the phase transition.Nudged elastic band calculations suggest that the activation barrier for flipping between"up"and"down"orientations of the NH_(4)^(+) cations is low in the ferroelectric phase,with the NH_(4)^(+) cations primarily interacting with the framework rather than neighbouring NH_(4)^(+)*cations.It is likely this motion that is responsible for scrambling the NH_(4)^(+) cation orientation locally in the ferroelectric phase.We propose that this disorder,with the same basic motion active above and below the phase transition,induces the significant dielectric relaxation in these materials.This suggests that orientational disorder may be an effective substitution for compositional disorder commonly associated with relaxor ferroelectrics in molecular materials.展开更多
Transmission electron microscopy(TEM)is an indispensable tool for elucidating the intrinsic atomic structures of materials and provides deep insights into defect dynamics,phase transitions,and nanoscale structural det...Transmission electron microscopy(TEM)is an indispensable tool for elucidating the intrinsic atomic structures of materials and provides deep insights into defect dynamics,phase transitions,and nanoscale structural details.While numerous intriguing physical properties have been revealed in recently discovered two-dimensional(2D)quantummaterials,many exhibit significant sensitivity towater and oxygen under ambient conditions.This inherent instability complicates sample preparation for TEM analysis and hinders accurate property measurements.This review highlights recent technical advancements to preserve the intrinsic structures of water-and oxygen-sensitive 2D materials for atomic-scale characterizations.A critical development discussed in this review is implementing an inert gas-protected glovebox integrated system(GIS)designed specifically for TEM experiments.In addition,this review emphasizes air-sensitivematerials such as 2D transitionmetal dichalcogenides,transition metal dihalides and trihalides,and low-dimensional magnetic materials,demonstrating breakthroughs in overcoming their environmental sensitivity.Furthermore,the progress in TEM characterization enabled by the GIS is analyzed to provide a comprehensive overview of state-of-the-art methodologies in this rapidly advancing field.展开更多
Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development.In this article,we have explored the C(sp2)–H alkenylation activity with novel spirocyclic N-heterocyclic carbene(NHC)-based cy...Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development.In this article,we have explored the C(sp2)–H alkenylation activity with novel spirocyclic N-heterocyclic carbene(NHC)-based cyclometalated ruthenium pincer catalyst system,SNRu-X.After screening catalyst and condition,a high valent Ru(Ⅳ)dioxide(X=O_(2))species has demonstrated superior reactivity in the catalytic alkenylation of aromatic and olefinic C–H bonds with unactivated alkenyl bromides and triflates.This reaction has achieved the easy construction of a wide range of(hetero)aromatic alkenes and dienes,in good to excellent yields with exclusive selectivity.Preliminary mechanistic studies indicate that this reaction may proceed through a single electron transfer(SET)triggered oxidative addition,by doing so,providing valuable complementary to classical alkenylation reactions that are dependent on activated alkenyl precursors.展开更多
Metal−nitrogen double bonds have been commonly reported for conventional metal complexes,but the coexistence of both transition metal−nitrogen and lanthanide−nitrogen double bonds bridged by nitrogen within one compou...Metal−nitrogen double bonds have been commonly reported for conventional metal complexes,but the coexistence of both transition metal−nitrogen and lanthanide−nitrogen double bonds bridged by nitrogen within one compound has never been reported.Herein,by encapsulating a ternary transition metallanthanide heteronuclear dimetallic nitride into a C_(84) fullerene cage,transition metal−nitrogen and lanthanide-nitrogen double bonds are costabilized simultaneously within the as-formed clusterfullerene TiCeN@C_(1)(12)-C_(84),which is a representative heteronuclear dimetallic nitride clusterfullerene.Its molecular structure was unambiguously determined by single-crystal X-ray diffraction,revealing a slightly bentμ2-bridged nitride cluster with short Ti−N(1.761Å)and Ce−N(2.109Å)bond lengths,which are comparable to the corresponding Ti=N and Ce=N double bonds of reported metal complexes and consistent with the theoretically predicted values,confirming their coexistence within TiCeN@C_(1)(12)-C_(84).Density functional theory(DFT)calculations unveil three-center two-electron(3c-2e)bonds delocalized over the entire TiCeN cluster,which are responsible for costabilization of Ti�N and Ce�N double bonds.An electronic configuration of Ti4+Ce^(3+)N^(3−)@C_(84)^(4−)is proposed featuring an intramolecular four-electron transfer,drastically different from the analogous actinide dimetallic nitride clusterfullerene(U_(2))^(9+)N^(3−)@C_(80)^(6−)and trimetallic nitride clusterfullerene(Sc_(2))^(6+)Ti^(3+)^(N3−)@C_(80)^(6−),indicating the peculiarity of 4-fold negatively charged fullerene cage in stabilizing the heteronuclear dimetallic nitride cluster.展开更多
Metallic-phase transition-metal dichalcogenides(TMDCs)exhibit unusual physicochemical properties compared with their semiconducting counterparts.However,they are thermodynamically unstable to access and it is even mor...Metallic-phase transition-metal dichalcogenides(TMDCs)exhibit unusual physicochemical properties compared with their semiconducting counterparts.However,they are thermodynamically unstable to access and it is even more challenging to construct their metastable-phase heterostructures.Herein,we demonstrate a general solution protocol for phase-controlled synthesis of distorted octahedral 1T WS2-based(1T structure denotes an octahedral coordination for W atom)multidimensional hybrid nanostructures from two-dimensional(2D),one-dimensional(1D),and zero-dimensional(0D)templates.This is realized by tuning the reactivity of tungsten precursor and the interaction between crystal surface and ligands.As a conceptual study on crystal phase-and dimensionality-dependent applications,we find that the three-dimensional(3D)hierarchical architectures achieved,comprising 1T WS2 and 2D Ni3S4,are very active and stable for catalyzing hydrogen evolution.Our results open up a new way to rationally design phase-controlled nanostructures with increased complexity and more elaborate functionalities.展开更多
The van der Waals interface structures and behaviors are of great impor-tance in determining the physical properties of two-dimensional atomic crystals and their heterostructures.The delicate interfacial properties ar...The van der Waals interface structures and behaviors are of great impor-tance in determining the physical properties of two-dimensional atomic crystals and their heterostructures.The delicate interfacial properties are sensitively dependent on the mechanical behaviors of atomically thin films under external strain.Here,we investigated the strain-engineered rippling structures at the CVD-grown bilayer-MoS_(2) interface with advanced atomic force microscopy(AFM).The in-plane compressive strain is sequentially introduced into the 1L-substrate and 2L-1L interface of bilayer-MoS_(2) flakes via a fast-cooling process.The thermal strain-engi-neered rippling structures were directly visualized at the central 2H-and 3R-MoS_(2) bilayer regions with friction force microscopy(FFM)and bimodal AFM techniques.These rippling structures can be further artifi-cially manipulated into the beating-like rippling features and fully erased via the contact mode AFM scanning.Our results shed lights on the strain-engineered interfacial structures of two-dimensional materials and also inspire the further investigation on the interface engineering of their elec-tronicandoptical properties.展开更多
基金supported by National Key R&D Program of China (Grant Nos.2022-YFA1403800,2023YFA1406000,and 2023YFA1406500)the National Natural Science Foundation of China (Grant Nos.12274459,12474002,22171283,and 52130103)+1 种基金China Postdoctoral Science Foundation (Grant No.2023M730011)supported by the Synergetic Extreme Condition User Facility (SECUF,https://cstr.cn/31123.02.SECUF)。
文摘Chiral topological semimetals hosting multifold fermions and exotic surface states represent a frontier in topological materials research. Among them, noncentrosymmetric cubic B20 compounds—notably transitionmetal silicides and germanides—offer a unique platform for realizing symmetry-protected topological phases and unconventional optoelectronic responses. Here, we report the physical properties of Rh Ge and Co Ge single crystals with B20 structure in detail. Transport measurements revea metallic behavior with characteristic Fermi-liquid scaling at low temperatures, while magnetization results confirm paramagnetism in both compounds. In addition,both materials exhibit low carrier concentrations with small electronic specific heat coefficients, indicating their semimetal feature with weak electronic correlations. Such high-quality Co Ge and Rh Ge single crystals provide a material platform to explore the evolution of multifold fermions and the instability of helicoid-arc surface states with spin–orbit coupling and surface environment in B20 material systems.
基金supported by National Natural Science Foundation of China(NSFC,Grant Nos.51702176,51572133,and 51972178)Zhejiang Provincial Nature Science Foundation(Grant No.LY20E020009)。
文摘The exploration of cheap,efficient,and durable bifunctional electrocatalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is highly desired to push forward the commercialization of rechargeable metal–air batteries.Here,bifunctional ORR/OER electrocatalysts based on CoxP(0<x<2,i.e.,Co_(2)P,Co_(2)P/CoP mixture,and CoP)nanoparticles(NPs)anchored on N,P-doped carbon framework(Co_(x)P@NPC)are developed via one-step carbonization of the mixture of as-synthesized ZIF-67 and melamine–phytic acid supermolecular aggregate(MPSA).The stoichiometric ratio of resultant Co_(x)P NPs can be rationally designed by adjusting the introduced ratio of ZIF-67 to MPSA,enabling their fabrication in a controlled manner.It is found that the as-synthesized Co_(2)P@NPC exhibits the best bifunctional ORR/OER activity among the Co_(x)P@NPC analogues,with a reversible oxygen electrode index(ΔE=E_(j10)−E_(1/2))down to~0.75 V.The constructed Zn–air battery based on Co_(2)P@NPC delivers a peak power density of 157 mW cm^(−2) and an excellent charge-discharge stability with negligible voltage decay for 140 h at 10 mA cm^(−2),superior to those based on Pt/C+RuO_(2) and most Co_(x)P-based electrodes ever reported.
基金Financial support from Ministerio de Ciencia e Innovación through projects PID2022-140143OB-I00(MCIN/AEI/10.13039/501100011033)and SO-CEX2019-000925-S(MCIN/AEI/10.13039/5011000110)supported by Marie Sk?odowska-Curie Actions Individual Fellowship grant funding to AMB,grant 101031365-SolTIMEthe support from the MSCA-COFUND I2:ICIQ Impulsion(GA 801474)。
文摘For carbon-free electrochemical fuel formation,the electrochemical cell must be powered by renewable energy.Obtaining solar-powered H_(2) fuel from water typically requires multiple photovoltaic cells and/or junctions to drive the water splitting reaction.Because of the lower thermodynamic requirements to oxidize ammonia compared to water,solar cells with smaller open circuit voltages can provide the required potential for ammonia splitting.In this work,a single perovskite solar cell with an open-circuit potential of 1.08 V is coupled to a 2-electrode electrochemical cell employing hybrid electroanodes functionalized with Ru-based molecular catalysts.The device is active for more than 30 min,producing N_(2) and H_(2) in a 1:2.9 ratio with 89%faradaic efficiency with no external applied bias.This work illustrates that hydrogen production from ammonia can be driven by conventional semiconductors.
文摘Four FeCO states with 3d4s and 3d3d electrons spinpaired or spinunpaired were examined to investigate the influences of pairing versus unpairing mechanisms upon the bonding and interaction in FeCO.The calculation results show that the FeCO bonding and interaction are determined by a balance between the bonding stabilization and the exchange stabilization with 3d4s electron spinpairing or without it.The 3d3d electron spinpairing versus unpairing has a surprised effect on the FeCO bonding properties even though the 3d orbitals are usually considered as non bonding ones.
基金financially supported by Higher Education Commission of Pakistan under Indigenous PhD 5000 Fellowship Program and International Research Support Initiative Program(IRSIP)
文摘A new complex C（18）H（24）CoF6N（12）Si has been synthesized by the reaction of cobalt（II） fluoride tetrahydrate with imidazole in a glass vessel. SiF62-was generated by in situ reaction of fluoride on silica. This complex has been characterized by different techniques such as elemental analysis, IR studies, magnetic measurements, electronic absorption measurements and single-crystal X-ray structure determination. The crystals are hexagonal in the R-3 space group, with a = 13.225（6）, b = 13.225（6）, c = 12.517（11） A, and g = 120°. In complex [Co（im）6]SiF6, the cobalt atom is six-coordinated to adopt a regular octahedral geometry and the SiF62-ion acts as the counter anion. The crystal displays a network structure and SiF62- bridging hexagram formation by N-（39）···F-Si interactions between imdazole and SiF62-. SiF62-plays an important role in assembling the supramolecular aggregates.
基金supported during this work through a Project Grant from the Leverhulme Trust(RPG-2018-288)Neutron diffraction and QENS experiments at the ISiS Pulsed Neutron and Muon Source were supported by a beamtime allocation from the Science and Technology Facilities Council(RB 1820062 and 1910402)We are grateful to the UK Materials and Molecular Modelling Hub for computational resources,which is partially fundedby EPSRC(EP/T022213/1,EP/W032260/1 and EP/P020194/1).
文摘Neutron diffraction studies of the low-temperature relaxor ferroelectric phases of[NH_(4)^(+)]M(HCO_(2))_(3),where M=Mn^(2+)and Zn^(2+),show that a third of the NH_(4)^(+)t cations remain subtly structurally disordered to low temperature.All NH_(4)^(+) cations within the channels are well separated from each other,with significant hydrogen bonds only with the anionic M(HCO_(2))_(3) framework.Complementary studies of the dynamics using ^(2)H solid state NMR and quasielastic neutron scattering indicate significant rotational motion in both paraelectric and ferroelectric phases,which evolves gradually with increasing temperature with no abrupt change at the phase transition.Nudged elastic band calculations suggest that the activation barrier for flipping between"up"and"down"orientations of the NH_(4)^(+) cations is low in the ferroelectric phase,with the NH_(4)^(+) cations primarily interacting with the framework rather than neighbouring NH_(4)^(+)*cations.It is likely this motion that is responsible for scrambling the NH_(4)^(+) cation orientation locally in the ferroelectric phase.We propose that this disorder,with the same basic motion active above and below the phase transition,induces the significant dielectric relaxation in these materials.This suggests that orientational disorder may be an effective substitution for compositional disorder commonly associated with relaxor ferroelectrics in molecular materials.
基金supported by the National Key Basic Research and Development Program of China,China(No.2024YFA1409100)support by the National Natural Science Foundation of China,China(Nos.52473302 and 12461160252)+4 种基金Guangdong Innovative and Entrepreneurial Research Team Program,China(No.2019ZT08C044)Guangdong Basic Science Foundation,China(2023B1515120039)Shenzhen Science and Technology Program,China(No.20200925161102001)the Science,Technology and Innovation Commission of Shenzhen Municipality,China(No.ZDSYS20190902092905285)Quantum Science Strategic Special Project from the Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area,China(No.GDZX2301006).
文摘Transmission electron microscopy(TEM)is an indispensable tool for elucidating the intrinsic atomic structures of materials and provides deep insights into defect dynamics,phase transitions,and nanoscale structural details.While numerous intriguing physical properties have been revealed in recently discovered two-dimensional(2D)quantummaterials,many exhibit significant sensitivity towater and oxygen under ambient conditions.This inherent instability complicates sample preparation for TEM analysis and hinders accurate property measurements.This review highlights recent technical advancements to preserve the intrinsic structures of water-and oxygen-sensitive 2D materials for atomic-scale characterizations.A critical development discussed in this review is implementing an inert gas-protected glovebox integrated system(GIS)designed specifically for TEM experiments.In addition,this review emphasizes air-sensitivematerials such as 2D transitionmetal dichalcogenides,transition metal dihalides and trihalides,and low-dimensional magnetic materials,demonstrating breakthroughs in overcoming their environmental sensitivity.Furthermore,the progress in TEM characterization enabled by the GIS is analyzed to provide a comprehensive overview of state-of-the-art methodologies in this rapidly advancing field.
基金suported by the National Natural Science Foundation of China(2187,1117,91956203)the“111”Program of Minister of Education,Beijing National Laboratory for Molecular Sciences(BNLMS202109)the Science and Technology Commission of Shanghai Municipality(19JC1430100)。
文摘Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development.In this article,we have explored the C(sp2)–H alkenylation activity with novel spirocyclic N-heterocyclic carbene(NHC)-based cyclometalated ruthenium pincer catalyst system,SNRu-X.After screening catalyst and condition,a high valent Ru(Ⅳ)dioxide(X=O_(2))species has demonstrated superior reactivity in the catalytic alkenylation of aromatic and olefinic C–H bonds with unactivated alkenyl bromides and triflates.This reaction has achieved the easy construction of a wide range of(hetero)aromatic alkenes and dienes,in good to excellent yields with exclusive selectivity.Preliminary mechanistic studies indicate that this reaction may proceed through a single electron transfer(SET)triggered oxidative addition,by doing so,providing valuable complementary to classical alkenylation reactions that are dependent on activated alkenyl precursors.
基金National Natural Science Foundation of China(51925206,U1932214,52302052,22301288)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0450301)+2 种基金Anhui Provincial Natural Science Foundation(2308085MB33,2308085MB31)Fundamental Research Funds for the Central Universities(20720220009,WK2060000051)National Synchrotron Radiation Laboratory(KY2060000240).
文摘Metal−nitrogen double bonds have been commonly reported for conventional metal complexes,but the coexistence of both transition metal−nitrogen and lanthanide−nitrogen double bonds bridged by nitrogen within one compound has never been reported.Herein,by encapsulating a ternary transition metallanthanide heteronuclear dimetallic nitride into a C_(84) fullerene cage,transition metal−nitrogen and lanthanide-nitrogen double bonds are costabilized simultaneously within the as-formed clusterfullerene TiCeN@C_(1)(12)-C_(84),which is a representative heteronuclear dimetallic nitride clusterfullerene.Its molecular structure was unambiguously determined by single-crystal X-ray diffraction,revealing a slightly bentμ2-bridged nitride cluster with short Ti−N(1.761Å)and Ce−N(2.109Å)bond lengths,which are comparable to the corresponding Ti=N and Ce=N double bonds of reported metal complexes and consistent with the theoretically predicted values,confirming their coexistence within TiCeN@C_(1)(12)-C_(84).Density functional theory(DFT)calculations unveil three-center two-electron(3c-2e)bonds delocalized over the entire TiCeN cluster,which are responsible for costabilization of Ti�N and Ce�N double bonds.An electronic configuration of Ti4+Ce^(3+)N^(3−)@C_(84)^(4−)is proposed featuring an intramolecular four-electron transfer,drastically different from the analogous actinide dimetallic nitride clusterfullerene(U_(2))^(9+)N^(3−)@C_(80)^(6−)and trimetallic nitride clusterfullerene(Sc_(2))^(6+)Ti^(3+)^(N3−)@C_(80)^(6−),indicating the peculiarity of 4-fold negatively charged fullerene cage in stabilizing the heteronuclear dimetallic nitride cluster.
基金supported by the National Natural Science Foundation of China(grant nos.21431006,21521001,and 21761132008)the Key Research Program of Frontier Sciences,CAS(grant no.QYZDJ-SSW-SLH036)+5 种基金the National Basic Research Program of China(grant no.2014CB931800)the Users with Excellence and Scientific Research Grant of Hefei Science Centre of CAS(grant no.2015HSC-UE007)S-K.H.acknowledges the Fundamental Research Funds for the Central Universities(grant no.PA2018GDQT0013)C.G.acknowledges the National Natural Science Foundation of China(grant no.21905261)the National Postdoctoral Program for Innovative Talents(grant no.BX20180284)the China Postdoctoral Science Foundation(grant no.2019M660155).
文摘Metallic-phase transition-metal dichalcogenides(TMDCs)exhibit unusual physicochemical properties compared with their semiconducting counterparts.However,they are thermodynamically unstable to access and it is even more challenging to construct their metastable-phase heterostructures.Herein,we demonstrate a general solution protocol for phase-controlled synthesis of distorted octahedral 1T WS2-based(1T structure denotes an octahedral coordination for W atom)multidimensional hybrid nanostructures from two-dimensional(2D),one-dimensional(1D),and zero-dimensional(0D)templates.This is realized by tuning the reactivity of tungsten precursor and the interaction between crystal surface and ligands.As a conceptual study on crystal phase-and dimensionality-dependent applications,we find that the three-dimensional(3D)hierarchical architectures achieved,comprising 1T WS2 and 2D Ni3S4,are very active and stable for catalyzing hydrogen evolution.Our results open up a new way to rationally design phase-controlled nanostructures with increased complexity and more elaborate functionalities.
基金supported by the National Key R&D Program of China(MOST)(Grant Nos.2023YFA1406500 and 2018YFE0202700)the National Natural Science Foundation of China(NSFC)(Nos.21622304,61674045,11604063,11974422,and 12104504)+2 种基金the Strategic Priority Research Program(Chinese Academy of Sciences,CAS)(No.XDB30000000)the Fundamental Research Funds for the Central Universities and the Research Funds of Renmin University of China[Nos.21XNLG27(Z.C.)and 22XNH095(H.D.)]supported by the Outstanding Innovative Talents Cultivation Funded Programs 2023 of Renmin University of China.
文摘The van der Waals interface structures and behaviors are of great impor-tance in determining the physical properties of two-dimensional atomic crystals and their heterostructures.The delicate interfacial properties are sensitively dependent on the mechanical behaviors of atomically thin films under external strain.Here,we investigated the strain-engineered rippling structures at the CVD-grown bilayer-MoS_(2) interface with advanced atomic force microscopy(AFM).The in-plane compressive strain is sequentially introduced into the 1L-substrate and 2L-1L interface of bilayer-MoS_(2) flakes via a fast-cooling process.The thermal strain-engi-neered rippling structures were directly visualized at the central 2H-and 3R-MoS_(2) bilayer regions with friction force microscopy(FFM)and bimodal AFM techniques.These rippling structures can be further artifi-cially manipulated into the beating-like rippling features and fully erased via the contact mode AFM scanning.Our results shed lights on the strain-engineered interfacial structures of two-dimensional materials and also inspire the further investigation on the interface engineering of their elec-tronicandoptical properties.
