The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the re...The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the realization of superconductivity in compressively strained La_(3)Ni_(2)O_(7)thin films grown on the SrLaAlO_(4)substrates,with a T_(c)exceeding 40 K,represents a significant step toward this goal.Here,we investigate the influence of film thickness and carrier doping on the electronic structure of La_(3)Ni_(2)O_(7)thin films,ranging from 0.5 to 3 unit cells,using first-principles calculations.For a 2 unit-cell film with an optimal doping concentration of 0.3 hole per formula unit(0.15 hole/Ni),the Ni-d_(z^(2))interlayer bonding state crosses the Fermi level,resulting in the formation ofγpockets at the Fermi surface.These findings align with angle-resolved photoemission spectroscopy experimental data.Our results provide theoretical validation for the recent experimental discovery of ambient-pressure superconductivity in La_(3)Ni_(2)O_(7)thin films and underscore the significant impact of film thickness and carrier doping on electronic property modulation.展开更多
Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the e...Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active sites.This optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of electrocatalysts.To elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization techniques.Importantly,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse reactions.This underscores the pivotal role of point defects in enhancing catalytic performance.At last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.展开更多
Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Her...Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Herein,with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern,the electronic structure is theoretically illustrated by the first-principles density functional theory calculations,suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI.It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal orbital Hamiltonian group analysis.The calculations of reaction free energy changes indicate that the oxygen evolution reaction should follow the reaction pathway of H_(2)O→^(*)OH→^(*)O→^(*)OOH→^(*)O_(2)with an overpotential of 0.81 V.Through an in-depth theoretical computational analysis in the atomic and electronic structures,the origin of photocatalytic oxygen evolution activity for PDI is well illustrated,which would help the rational design and modification of polymeric photocatalysts for efficient oxygen evolution.展开更多
Thework presents the electronic structure computations and optical spectroscopy studies of half-Heusler ScNiBi and YNiBi compounds.Our first-principles computations of the electronic structures were based on density f...Thework presents the electronic structure computations and optical spectroscopy studies of half-Heusler ScNiBi and YNiBi compounds.Our first-principles computations of the electronic structures were based on density functional theory accounting for spin-orbit coupling.These compounds are computed to be semiconductors.The calculated gap values make ScNiBi and YNiBi valid for thermoelectric and optoelectronic applications and as selective filters.In ScNiBi and YNiBi,an intense peak at the energy of−2 eV is composed of theNi 3d states in the conduction band,and the valence band mostly contains these states with some contributions from the Bi 6p and Sc 3d or Y 4d electronic states.These states participate in the formation of the indirect gap of 0.16 eV(ScNiBi)and 0.18 eV(YNiBi).Within the spectral ellipsometry technique in the interval 0.22–15μm of wavelength,the optical functions of materials are studied,and their dispersion features are revealed.A good matching of the experimental and modeled optical conductivity spectra allowed us to analyze orbital contributions.The abnormally low optical absorption observed in the low-energy region of the spectrum is referred to as the results of band calculations indicating a small density of electronic states near the Fermi energy of these complex materials.展开更多
Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled t...Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled thermomechanical fields remains insufficiently understood.In this study,transmission and scanning electron microscopy were employed to observe dislocation structures and grain boundary heterogeneities in processed aluminum alloys,suggesting stress concentrations and microstructural inhomogeneities associated with vacancy accumulation.To complement these observations,first-principles calculations and molecular dynamics simulations were conducted for seven single-vacancy configurations in face-centered cubic aluminum.The stress response,total energy,density of states(DOS),and differential charge density were examined under varying compressive strain(ε=0–0.1)and temperature(0–600 K).The results indicate that face-centered vacancies tend to reduce mechanical strength and perturb electronic states near the Fermi level,whereas corner and edge vacancies appear to have weaker effects.Elevated temperatures may partially restore electronic uniformity through thermal excitation.Overall,these findings suggest that vacancy position exerts a critical but position-dependent influence on coupled structure-property relationships,offering theoretical insights and preliminary experimental support for defect-engineered aluminum alloy design.展开更多
Fabricating a durable electrocatalyst with performance comparable to noble metals for the alkaline hydrogen evolution reaction(HER)remains a significant challenge.In this work,we introduce a highly efficient and robus...Fabricating a durable electrocatalyst with performance comparable to noble metals for the alkaline hydrogen evolution reaction(HER)remains a significant challenge.In this work,we introduce a highly efficient and robust electrocatalyst by incorporating rhenium(Re)atoms into CoS nanoflakes(Re-CoS)for alkaline HER.The incorporation of Re atoms into the CoS lattice enhances the hybridization of Co 3d and S 2p orbitals,resulting in an optimized electronic structure that accelerates water dissociation on Co sites and optimizes hydrogen adsorptiondesorption on S sites,thereby boosting the HER rate.The optimal Re-CoS catalyst demonstrates a low overpotential of 72 mV at 10 mA cm^(-2)in 1 M KOH,along with excellent long-term stability,maintaining its catalytic activity over 200 h without significant degradation.These results suggest that the incorporation of Re atoms into CoS effectively couples the water dissociation and hydrogen addesorption steps of alkaline HER,offering a promising strategy for the development of noble metal-like electrocatalysts.展开更多
Diradicaloid polycyclic hydrocarbons(PHs)own unique open-shell electronic structures and exhibit potential utility in the fields of organic electronics and spintronics.Herein,we disclose precise fusion of B/O-heterocy...Diradicaloid polycyclic hydrocarbons(PHs)own unique open-shell electronic structures and exhibit potential utility in the fields of organic electronics and spintronics.Herein,we disclose precise fusion of B/O-heterocycles onto PHs for control over their electronic structures and diradical properties.We designed and synthesized four B/O-containing diradicaloid isomers that feature the fluoreno[3,2-b]fluorene and fluoreno[2,1-a]fluoreneπ-skeletons,respectively.The precise B/O-heterocycle fusion modes along with the changed conjugation patterns lead to their modulated electronic structures and properties,such as diradical and aromatic structures,energy levels and band gaps,as well as magnetic,electrochemical and photophysical properties.Notably,the mode A may decrease the open-shell extent,whereas the mode B can enhance the diradical nature,leading to their well-tuned diradical characters in the range of0.46-0.70.Moreover,the mode A stabilizes the LUMOs and the mode B obviously increases the HOMO levels,which are remarkably contributed by the B and O atoms,respectively,further giving rise to the decreased band gaps and redshifted absorptions.This study clearly illustrates the electronic effects of B/O-heterocycle fusion on PHs and gains insight into B/O-type organic diradicaloids.These findings will provide an important guideline for the design of more fascinating heteroatom-containing diradicaloids.展开更多
Iron oxide nanoparticles(IONPs)with intrinsic peroxidase(POD)-mimic activity have gained significant attention as nanozymes.Reducing sizes of IONPs is the mostly applied strategy to boost their enzymatic activity due ...Iron oxide nanoparticles(IONPs)with intrinsic peroxidase(POD)-mimic activity have gained significant attention as nanozymes.Reducing sizes of IONPs is the mostly applied strategy to boost their enzymatic activity due to their high specific surface areas.Herein,we synthesized a series of uniformly sized IONPs ranging from3.17 to 21.2 nm,and found that POD activity of IONPs is not monotone increased by reducing their sizes,with the optimal size of 7.82 nm rather than smaller sized 3.17 nm.The reason for this unnormal phenomenon is that electronic structure also had great influence on POD activity,especially at the ultrasmall size region.Since Fe^(2+)are with higher enzymatic activity than Fe^(3+),3.17 nm IONPs although have the largest specific surface area,are prone to be oxidized,which reduced their iron content and ratio of Fe^(2+)to Fe^(3+),and consequently decreased their POD activity.By intentionally oxidized 7.82 nm IONPs in air,POD activity was obviously reduced,illustrating electronic structure cannot be overlooked.At the larger sized region ranging from 7.82 to 21.2 nm,oxidation degree of IONPs is similar,and surface electronic structure had a negligible effect on POD activity,and therefore,POD activity is predominantly influenced by specific surface area.By using the optimized 7.82 nm IONPs,tumor growth was obviously inhibited,demonstrating their potential in cancer therapeutics.Our results reveal that the designing of nanozymes should comprehensively balance their influence of surface electronic structure and specific surface area.展开更多
As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)poss...As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.展开更多
Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic ...Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic supramolecular self-assembly strategy to fabricate 3D hierarchical porous nanoribbon assembly Mn-VN cardoons.A bimetallic polyoxovanadate(POV)with the inherent structural feature of Mn surrounded by[VO_(6)]octahedrons was introduced to trigger precise Mn incorporation in VN lattice,thereby achieving simultaneous morphology engineering and electronic structure modulation.The lattice contraction of VN caused by Mn incorporation drives electron redistribution.The unique hierarchical architecture with modulated electronic structure that provides more exposed active sites,facilitates mass and charge transfer,and optimizes the associated adsorption behavior.Mn-VN exhibits excellent activity with low overpotentials of 86 m V and 1.346 V at 10 m A/cm^(2)for hydrogen evolution reaction(HER)and urea oxidation reaction(UOR),respectively.Accordingly,in the two-electrode urea-assisted water electrolyzer utilizing Mn-VN as a bifunctional catalyst,hydrogen production can occur at low voltage(1.456 V@10 m A/cm^(2)),which has the advantages of energy saving and competitive durability over traditional water electrolysis.This work provides a simple and mild route to construct nanostructures and modulate electronic structure for designing high-efficiency electrocatalysts.展开更多
Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still r...Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still remains a great challenge.In this work,Fe atom clusters(Fe_(AC))modified by high-density Cu single atoms(Cu_(SA))in a N,S-doped porous carbon substrate(Fe_(AC)/Cu_(SA)@NCS)is reported for enhanced ORR electrocatalysis.Fe_(AC)/Cu_(SA)@NCS exhibits excellent ORR performance with a half-wave potential(E_(1/2))of 0.911 V,a high four-electron process selectivity and excellent stability.The ORR performance is also verified in the Fe_(AC)/Cu_(SA)@NCS-based Zn-air battery,which shows a high peak power density of 192.67 mW cm^(-2),a higher specific capacity of 808.3 mAh g^(-1)and impressive charge-discharge cycle stability.Moreover,density functional theory calculations show that Cu single atoms synergistically modulate the electronic structure Fe active atoms in Fe atomic clusters,reducing the energy barrier of the rate-determining step(i.e.,*OH desorption)on Fe_(AC)/Cu_(SA)@NCS.This work provides an effective way to regulate the electronic structure of Fe-based catalysts and optimize their electrocatalytic activity based on the introduction of a second metal source.展开更多
High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors,single-charge detection,and memory devices.Here we systematically investigated the electronic properti...High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors,single-charge detection,and memory devices.Here we systematically investigated the electronic properties of single-walled boron antimonide(BSb)nanotubes using first-principles calculations.We observed that rolling the hexagonal boron antimonide monolayer into armchair(ANT)and zigzag(ZNT)nanotubes induces compression and wrinkling effects,significantly modifying the band structures and carrier mobilities through band folding andπ^(*)-σ^(*)hybridization.As the chiral index increases,the band gap and carrier mobility of ANTs decrease monotonically,where electron mobility consistently exceeds hole mobility.In contrast,ZNTs exhibit a more complex trend:the band gap first increases and then decreases,and the carrier mobility displays oscillatory behavior.In particular,both ANTs and ZNTs could exhibit significantly higher carrier mobilities compared to hexagonal monolayer and zinc-blende BSb,reaching 10^(-3)-10^(-7) cm^(-2)·V^(-1)·s^(-1).Our findings highlight strong curvature-induced modifications in the electronic properties of single-walled BSb nanotubes,demonstrating the latter as a promising candidate for high-performance electronic devices.展开更多
Triggering structural asymmetry can induce charge redistribution and modify electronic structures,which is of great significance for the design of high-performance hydrogen oxidation reaction(HOR)electrocatalysts.Here...Triggering structural asymmetry can induce charge redistribution and modify electronic structures,which is of great significance for the design of high-performance hydrogen oxidation reaction(HOR)electrocatalysts.Herein,we propose a dual anion-induced strategy to create an innovative RuS_(2)-RuO_(2)heterostructure featuring abundant S-Ru-O interfaces(RuS_(2)-RuO_(2)@C).This RuS_(2)-RuO_(2)@C demonstrates an impressive mass activity of 2.61 mAμg_(RU)^(-1)and an exchange current density of 2.96 mA cm^(-2),surpassing Pt/C and other comparative samples by over 20 times.Durability assessments confirm the superior stability of RuS_(2)-RuO_(2)@C,with only minimal performance loss during operation.Density functional theory(DFT)calculations indicate that the asymmetric S-Ru-O configuration optimizes the interfacial electronic structure and shifts the d-band center closer to the Fermi level,effectively reducing the energy barrier of the rate-determining step(RDS)in the alkaline HOR process.Moreover,in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy(ATR-SEIRAS)characteristics disclose the formation of a substantial hydrogen bond network at the S-Ru-o interface,which aids in the desorption of H_(2)O_(ad)and facilitates the vital Volmer step in the HOR pathway.展开更多
Photocatalytic synthesis of hydrogen peroxide(H_(2)O_(2))has emerged as a promising approach because of its simplicity and environmental benefits.However,significant challenges remain obstacles to their advancement,su...Photocatalytic synthesis of hydrogen peroxide(H_(2)O_(2))has emerged as a promising approach because of its simplicity and environmental benefits.However,significant challenges remain obstacles to their advancement,such as the rapid recombination of photogenerated charge carriers and sluggish surface redox reactions on nonmetallic organic catalysts.Metal-based organic catalysts with tunable electronic structures are considered ideal for exploring the mechanisms and structure-performance relationships in H_(2)O_(2) synthesis.This review summarizes the fundamental principles of photocatalytic H_(2)O_(2) synthesis via oxygen reduction and water oxidation reactions.Recent advancements in electronic structure tuning strategies for metal-based organic catalysts are critically examined,focusing on their impact on light absorption range,photogenerated carrier separation,O_(2) activation,and the selective generation of H_(2)O_(2).In addition,this review comprehensively evaluates the applications of sacrificial agents in photocatalytic reaction systems and offers insights into the future development of metal-based organic catalysts for H_(2)O_(2) photosynthesis.展开更多
Determining the electronic structure of La_(3)Ni_(2)O_(7)is an essential step towards uncovering its superconducting mechanism.It is widely believed that the bilayer apical oxygens play an important role in the bilaye...Determining the electronic structure of La_(3)Ni_(2)O_(7)is an essential step towards uncovering its superconducting mechanism.It is widely believed that the bilayer apical oxygens play an important role in the bilayer La_(3)Ni_(2)O_(7)electronic structure.Applying the hybrid exchange–correlation functionals,we obtain a more accurate electronic structure of La_(3)Ni_(2)O_(7)at its high-pressure phase,where the bonding dz2 band is below the Fermi level owing to the apical oxygen.The symmetry properties of this electronic structure and its corresponding tight-binding model are further analyzed.We find that the antisymmetric part is highly entangled,leading to a minimal nearly degenerate two-orbital model.Then,the apical oxygen vacancies effect is studied using the dynamical cluster approximation.This disorder effect strongly destroys the antisymmetric b Fermi surface,leading to the possible disappearance of superconductivity.展开更多
We theoretically investigate the electronic structure of cylindrical magnetic topological insulator quantum wires in MnBi_(2)Te_(4).Our study reveals the emergence of topological surface states in the ferromagnetic ph...We theoretically investigate the electronic structure of cylindrical magnetic topological insulator quantum wires in MnBi_(2)Te_(4).Our study reveals the emergence of topological surface states in the ferromagnetic phase,characterized by spin-polarized subbands resulting from intrinsic magnetization.In the antiferromagnetic phase,we identify the coexistence of three distinct types of topological states,encompassing both surface states and central states.展开更多
The binding energy spectra and electron momentum distributions(EMDs)of valence orbitals in toluene molecule were measured by(e,2e)electron momentum spectrometer.A comprehensive analysis of molecular vibrational effect...The binding energy spectra and electron momentum distributions(EMDs)of valence orbitals in toluene molecule were measured by(e,2e)electron momentum spectrometer.A comprehensive analysis of molecular vibrational effects on the EMDs was conducted through harmonic analytical quantum mechanical approach calculations and molecular dynamics simulations within the plane wave impulse approximation(PWIA).Furthermore,the multicenter three-distorted-wave method was employed to investigate the validity of the PWIA.A comparison between experimental measurements and theoretical predictions demonstrates that molecular vibrations have negligible effects on the EMDs,whereas the distorted-wave effects are obvious,particularly in large momentum regions.展开更多
We present a comprehensive electron momentum spectroscopy study on the electronic structure of trifluorobromomethane.The binding energy spectrum and electron momentum profiles of the entire outer-valence orbitals and ...We present a comprehensive electron momentum spectroscopy study on the electronic structure of trifluorobromomethane.The binding energy spectrum and electron momentum profiles of the entire outer-valence orbitals and the first inner-valence orbital along with several shake-up states were measured by using a high-sensitivity(e,2e)apparatus at an electron impact energy of 1213 eV.Theoretical calculations employing the density functional theory with B3LYP hybrid functional and the symmetry-adapted cluster configuration-interaction method were performed to interpret the experimental results.Important effects of electron correlations in the initial neutral and final ionic states on the electron momentum profiles have been observed.展开更多
The rapidly growing electric cars and energy storage systems have extremely promoted the development of advanced lithium and sodium ion batteries and stimulated evolution of high-capacity cathodes.Li/Na-rich layered c...The rapidly growing electric cars and energy storage systems have extremely promoted the development of advanced lithium and sodium ion batteries and stimulated evolution of high-capacity cathodes.Li/Na-rich layered cathodes consisting cationic and anionic reactions as the most typical representative of high-capacity cathodes have shown its tremendous potential.However,there is a long way to go before commercialization because of unsatisfactory performances including large voltage hysteresis,voltage fade and poor cycle performance.Numerous investigations on redox mechanisms and engineering strategies have been performed from the point view of structure and made significant progress,which has been well reviewed.Meanwhile,the unacceptable issues are essentially correlated to the electronic configuration of anionic redox and its interaction with adjacent transition metal cations,which can be well depicted from electronic structure.However,the investigations on anionic reaction process in the viewpoint of electronic structure have been much less summarized.This review aims to compile the current knowledge of anionic redox from the point view of electronic structure,including configuration,origination,evolution,detection and coupling relationship with cationic redox.This work is attempted to inspire new perspectives and design approaches for the development of high-capacity cathodes.展开更多
Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four plan...Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four planar N-coordination and one axial P-coordination(Co-N_(4)P_(1))are decorated on the lateral edges of nanorod-like crystalline g-C_(3)N_(4)(CCN)photocatalysts.Significantly,the electronic structures of central Co as active sites for O_(2) reduction reaction(ORR)and planar N-coordinator as active sites for H_(2)O oxidation reaction(WOR)in Co-N_(4)P_(1) can be well regulated by the synergetic effects of introducing axial P-coordinator,in contrast to the decorated Co single-atoms with only four planar N-coordination(Co-N_(4)).Specifically,directional photoelectron accumulation at central Co active sites,induced by an introduced midgap level in Co-N_(4)P_(1),mediates the ORR active sites from 4e–-ORR-selective terminal–NH_(2) sites to 2e–-ORR-selective Co sites,moreover,an elevated d-band center of Co 3d orbital strengthens ORR intermediate*OOH adsorption,thus jointly facilitating a highly selective and active 2e^(–)-ORR pathway to H_(2)O_(2) photosynthesis.Simultaneously,a downshifted p-band center of N_(2)p orbital in Co-N_(4)P_(1) weakens WOR intermediate*OH adsorption,thus enabling a preferable 2e^(–)-WOR pathway toward H_(2)O_(2) photosynthesis.Subsequently,Co-N_(4)P_(1) exhibits exceptional H_(2)O_(2) photosynthesis efficiency,reaching 295.6μmol g^(-1) h^(-1) with a remarkable solar-to-chemical conversion efficiency of 0.32%,which is 15 times that of Co-N_(4)(19.2μmol g^(-1) h^(-1))and 10 times higher than CCN(27.6μmol g^(-1) h^(-1)).This electronic structure modulation on single-atom catalysts offers a promising strategy for boosting the activity and selectivity of H_(2)O_(2) photosynthesis.展开更多
基金supported by the National Key R&D Program of China(Gran Nos.2022YFA1402304 and 2022YFA1402802)the National Natural Science Foundation of China(Grant Nos.12494591,12122405,12274169,and 92165204)+4 种基金Program for Science and Technology Innovation Team in Zhejiang(Grant No.2021R01004)Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices(Grant No.2022B1212010008)Guangdong Fundamental Research Center for Magnetoelectric Physics(2024B0303390001)Guangdong Provincial Quantum Science Strategic Initiative(Grant No.GDZX2401010)the Fundamental Research Funds for the Central Universities。
文摘The discovery of high-temperature superconductivity in bilayer nickelate La_(3)Ni_(2)O_(7)under high-pressure conditions has spurred extensive efforts to stabilize superconductivity at ambient pressure.Recently,the realization of superconductivity in compressively strained La_(3)Ni_(2)O_(7)thin films grown on the SrLaAlO_(4)substrates,with a T_(c)exceeding 40 K,represents a significant step toward this goal.Here,we investigate the influence of film thickness and carrier doping on the electronic structure of La_(3)Ni_(2)O_(7)thin films,ranging from 0.5 to 3 unit cells,using first-principles calculations.For a 2 unit-cell film with an optimal doping concentration of 0.3 hole per formula unit(0.15 hole/Ni),the Ni-d_(z^(2))interlayer bonding state crosses the Fermi level,resulting in the formation ofγpockets at the Fermi surface.These findings align with angle-resolved photoemission spectroscopy experimental data.Our results provide theoretical validation for the recent experimental discovery of ambient-pressure superconductivity in La_(3)Ni_(2)O_(7)thin films and underscore the significant impact of film thickness and carrier doping on electronic property modulation.
基金supported by the National Natural Science Foundation of China(U21A20281)the Special Fund for Young Teachers from Zhengzhou University(JC23557030,JC23257011)+1 种基金the Key Research Projects of Higher Education Institutions of Henan Province(24A530009)the Project of Zhongyuan Critical Metals Laboratory(GJJSGFYQ202336).
文摘Point defect engineering endows catalysts with novel physical and chemical properties,elevating their electrocatalytic efficiency.The introduction of defects emerges as a promising strategy,effectively modifying the electronic structure of active sites.This optimization influences the adsorption energy of intermediates,thereby mitigating reaction energy barriers,altering paths,enhancing selectivity,and ultimately improving the catalytic efficiency of electrocatalysts.To elucidate the impact of defects on the electrocatalytic process,we comprehensively outline the roles of various point defects,their synthetic methodologies,and characterization techniques.Importantly,we consolidate insights into the relationship between point defects and catalytic activity for hydrogen/oxygen evolution and CO_(2)/O_(2)/N_(2) reduction reactions by integrating mechanisms from diverse reactions.This underscores the pivotal role of point defects in enhancing catalytic performance.At last,the principal challenges and prospects associated with point defects in current electrocatalysts are proposed,emphasizing their role in advancing the efficiency of electrochemical energy storage and conversion materials.
基金supported by National Natural Science Foundation of China(No.523B2070,No.52225606).
文摘Polymeric perylene diimide(PDI)has been evidenced as a good candidate for photocatalytic water oxidation,yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration.Herein,with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern,the electronic structure is theoretically illustrated by the first-principles density functional theory calculations,suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI.It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal orbital Hamiltonian group analysis.The calculations of reaction free energy changes indicate that the oxygen evolution reaction should follow the reaction pathway of H_(2)O→^(*)OH→^(*)O→^(*)OOH→^(*)O_(2)with an overpotential of 0.81 V.Through an in-depth theoretical computational analysis in the atomic and electronic structures,the origin of photocatalytic oxygen evolution activity for PDI is well illustrated,which would help the rational design and modification of polymeric photocatalysts for efficient oxygen evolution.
文摘Thework presents the electronic structure computations and optical spectroscopy studies of half-Heusler ScNiBi and YNiBi compounds.Our first-principles computations of the electronic structures were based on density functional theory accounting for spin-orbit coupling.These compounds are computed to be semiconductors.The calculated gap values make ScNiBi and YNiBi valid for thermoelectric and optoelectronic applications and as selective filters.In ScNiBi and YNiBi,an intense peak at the energy of−2 eV is composed of theNi 3d states in the conduction band,and the valence band mostly contains these states with some contributions from the Bi 6p and Sc 3d or Y 4d electronic states.These states participate in the formation of the indirect gap of 0.16 eV(ScNiBi)and 0.18 eV(YNiBi).Within the spectral ellipsometry technique in the interval 0.22–15μm of wavelength,the optical functions of materials are studied,and their dispersion features are revealed.A good matching of the experimental and modeled optical conductivity spectra allowed us to analyze orbital contributions.The abnormally low optical absorption observed in the low-energy region of the spectrum is referred to as the results of band calculations indicating a small density of electronic states near the Fermi energy of these complex materials.
基金supported by the Research Project on Strengthening the Construction of an Important Ecological Security Barrier in Northern China by Higher Education Institutions in the Inner Mongolia Autonomous Region(STAQZX202313)the Inner Mongolia Autonomous Region Education Science‘14th Five-Year Plan’2024 Annual Research Project(NGJGH2024635).
文摘Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled thermomechanical fields remains insufficiently understood.In this study,transmission and scanning electron microscopy were employed to observe dislocation structures and grain boundary heterogeneities in processed aluminum alloys,suggesting stress concentrations and microstructural inhomogeneities associated with vacancy accumulation.To complement these observations,first-principles calculations and molecular dynamics simulations were conducted for seven single-vacancy configurations in face-centered cubic aluminum.The stress response,total energy,density of states(DOS),and differential charge density were examined under varying compressive strain(ε=0–0.1)and temperature(0–600 K).The results indicate that face-centered vacancies tend to reduce mechanical strength and perturb electronic states near the Fermi level,whereas corner and edge vacancies appear to have weaker effects.Elevated temperatures may partially restore electronic uniformity through thermal excitation.Overall,these findings suggest that vacancy position exerts a critical but position-dependent influence on coupled structure-property relationships,offering theoretical insights and preliminary experimental support for defect-engineered aluminum alloy design.
基金financially supported by the Institute for Basic Science of Korea(No.IBS-R011-D1)the National Research Foundation of Korea(NRF)(No.NRF-2022R1A2C2093415)+5 种基金the Korea Basic Science Institute(National Research Facilities and Equipment Center)grant funded by the Ministry of Education(No.2022R1A6C101A751)the National Natural Science Foundation of China(Nos.22209186 and 22479149)the Natural Science Foundation of Jiangxi Province(No.310306484080)the Key Research and Development Program of Jiangxi Province(Nos.20223BBG74004 and 20232BBG70003)the Youth Innovation Promotion Association,Chinese Academy of Sciences(No.2023343)the financial support from the National Research Foundation of Korea Grant funded by the Korean government(NRF-2021R1I1A1A01050068)
文摘Fabricating a durable electrocatalyst with performance comparable to noble metals for the alkaline hydrogen evolution reaction(HER)remains a significant challenge.In this work,we introduce a highly efficient and robust electrocatalyst by incorporating rhenium(Re)atoms into CoS nanoflakes(Re-CoS)for alkaline HER.The incorporation of Re atoms into the CoS lattice enhances the hybridization of Co 3d and S 2p orbitals,resulting in an optimized electronic structure that accelerates water dissociation on Co sites and optimizes hydrogen adsorptiondesorption on S sites,thereby boosting the HER rate.The optimal Re-CoS catalyst demonstrates a low overpotential of 72 mV at 10 mA cm^(-2)in 1 M KOH,along with excellent long-term stability,maintaining its catalytic activity over 200 h without significant degradation.These results suggest that the incorporation of Re atoms into CoS effectively couples the water dissociation and hydrogen addesorption steps of alkaline HER,offering a promising strategy for the development of noble metal-like electrocatalysts.
基金supported by National Natural Science Foundation of China(Nos.52373182 and 22175074)Jilin Scientific and Technological Development Program(No.20220101054JC)Department of Education of Jilin Province(No.JJKH20221046KJ)。
文摘Diradicaloid polycyclic hydrocarbons(PHs)own unique open-shell electronic structures and exhibit potential utility in the fields of organic electronics and spintronics.Herein,we disclose precise fusion of B/O-heterocycles onto PHs for control over their electronic structures and diradical properties.We designed and synthesized four B/O-containing diradicaloid isomers that feature the fluoreno[3,2-b]fluorene and fluoreno[2,1-a]fluoreneπ-skeletons,respectively.The precise B/O-heterocycle fusion modes along with the changed conjugation patterns lead to their modulated electronic structures and properties,such as diradical and aromatic structures,energy levels and band gaps,as well as magnetic,electrochemical and photophysical properties.Notably,the mode A may decrease the open-shell extent,whereas the mode B can enhance the diradical nature,leading to their well-tuned diradical characters in the range of0.46-0.70.Moreover,the mode A stabilizes the LUMOs and the mode B obviously increases the HOMO levels,which are remarkably contributed by the B and O atoms,respectively,further giving rise to the decreased band gaps and redshifted absorptions.This study clearly illustrates the electronic effects of B/O-heterocycle fusion on PHs and gains insight into B/O-type organic diradicaloids.These findings will provide an important guideline for the design of more fascinating heteroatom-containing diradicaloids.
基金financially supported by the Natural Science Foundation of Zhejiang Province(No.LR22E010001)the National Natural Science Foundation of China(No.52073258)+1 种基金the Fundamental Research Funds for the Provincial Universities of Zhejiang(No.RF-B2022006)the R&D Program of Zhejiang University of Technology(No.KYY-HX-20190730)
文摘Iron oxide nanoparticles(IONPs)with intrinsic peroxidase(POD)-mimic activity have gained significant attention as nanozymes.Reducing sizes of IONPs is the mostly applied strategy to boost their enzymatic activity due to their high specific surface areas.Herein,we synthesized a series of uniformly sized IONPs ranging from3.17 to 21.2 nm,and found that POD activity of IONPs is not monotone increased by reducing their sizes,with the optimal size of 7.82 nm rather than smaller sized 3.17 nm.The reason for this unnormal phenomenon is that electronic structure also had great influence on POD activity,especially at the ultrasmall size region.Since Fe^(2+)are with higher enzymatic activity than Fe^(3+),3.17 nm IONPs although have the largest specific surface area,are prone to be oxidized,which reduced their iron content and ratio of Fe^(2+)to Fe^(3+),and consequently decreased their POD activity.By intentionally oxidized 7.82 nm IONPs in air,POD activity was obviously reduced,illustrating electronic structure cannot be overlooked.At the larger sized region ranging from 7.82 to 21.2 nm,oxidation degree of IONPs is similar,and surface electronic structure had a negligible effect on POD activity,and therefore,POD activity is predominantly influenced by specific surface area.By using the optimized 7.82 nm IONPs,tumor growth was obviously inhibited,demonstrating their potential in cancer therapeutics.Our results reveal that the designing of nanozymes should comprehensively balance their influence of surface electronic structure and specific surface area.
基金supported by the National Natural Science Foundation of China(NSFC)(Nos.22178148 and 22278193)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘As a catalyst of the air cathode in zinc-air batteries,tungstic acid ferrous(FeWO_(4)),a nanoscale transition metal tungstate,shows a broad application prospect in the oxygen reduction reaction(ORR).While FeWO_(4)possesses favorable electrochemical properties and thermodynamic stability,its intrinsic semiconductor characteristics result in a relatively slow electron transfer rate,limiting the ORR catalytic activity.In this work,the electronic structure of FeWO_(4)is significantly modulated by introducing phosphorus(P)atoms with abundant valence electrons.The P doping can adjust the electronic structure of FeWO_(4)and then optimize oxygen-containing intermediates'absorption/desorption efficiency to achieve improved ORR activity.Furthermore,the sodium chloride template is utilized to construct a porous carbon framework for anchoring phosphorus-doped iron tungstate(P-FeWO_(4)/PNC).The porous carbon skeleton provides numerous active sites for the absorption/desorption and redox reactions on the P-FeWO_(4)/PNC surface and serves as mass transport channels for reactants and intermediates.The P-FeWO_(4)/PNC demonstrates ORR performance(E1/2=0.86 V vs.RHE).Furthermore,the zinc-air batteries incorporating the P-FeWO_(4)/PNC composite demonstrate an increased peak power density(172.2 mW·cm^(-2)),high specific capacity(810.1 mAh·g^(-1)),and sustained long-term cycling stability lasting up to 240 h.This research not only contributes to the advancement of cost-effective tungsten-based non-precious metallic ORR catalysts,but also guides their utilization in zinc-air batteries.
基金supported by the National Natural Science Foundation of China(Nos.22322104,22171074)the Natural Science Foundation of Heilongjiang Province(No.YQ2021B009)+3 种基金the Reform and Development Fund Project of Local University supported by the Central Government(Outstanding Youth Program)Heilongjiang Province Young Scientific and Technological Talent Lifting Project(No.2023QNTJ019)the Basic Research Support Project for Outstanding Young Teachers in Heilongjiang Provincial University(No.YQJH2023129)the Outstanding Youth Science Foundation of Heilongjiang University(No.JCL202301)。
文摘Urea-assisted water electrolysis offers a promising route to reduce energy consumption for hydrogen production and meanwhile treat urea-rich wastewater.Herein,we devised a shear force-involved polyoxometalate-organic supramolecular self-assembly strategy to fabricate 3D hierarchical porous nanoribbon assembly Mn-VN cardoons.A bimetallic polyoxovanadate(POV)with the inherent structural feature of Mn surrounded by[VO_(6)]octahedrons was introduced to trigger precise Mn incorporation in VN lattice,thereby achieving simultaneous morphology engineering and electronic structure modulation.The lattice contraction of VN caused by Mn incorporation drives electron redistribution.The unique hierarchical architecture with modulated electronic structure that provides more exposed active sites,facilitates mass and charge transfer,and optimizes the associated adsorption behavior.Mn-VN exhibits excellent activity with low overpotentials of 86 m V and 1.346 V at 10 m A/cm^(2)for hydrogen evolution reaction(HER)and urea oxidation reaction(UOR),respectively.Accordingly,in the two-electrode urea-assisted water electrolyzer utilizing Mn-VN as a bifunctional catalyst,hydrogen production can occur at low voltage(1.456 V@10 m A/cm^(2)),which has the advantages of energy saving and competitive durability over traditional water electrolysis.This work provides a simple and mild route to construct nanostructures and modulate electronic structure for designing high-efficiency electrocatalysts.
基金financially supported by the National Natural Science Foundation of China(No.22278042)the National Natural Science Foundation of Jiangsu Province(No.BK20240567)+2 种基金the Introduction and Cultivation of Leading Innovative Talents Foundation of Changzhou,Jiangsu Province(No.CQ20220093)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(No.24KJD530001)the Open Project Program of Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science(No.M2024-7),MOE
文摘Regulating the electronic structure and oxygencontaining intermediates adsorption behavior on Fe-based catalysts is of great significance to cope with the sluggish oxygen reduction reaction(ORR)kinetics,but it still remains a great challenge.In this work,Fe atom clusters(Fe_(AC))modified by high-density Cu single atoms(Cu_(SA))in a N,S-doped porous carbon substrate(Fe_(AC)/Cu_(SA)@NCS)is reported for enhanced ORR electrocatalysis.Fe_(AC)/Cu_(SA)@NCS exhibits excellent ORR performance with a half-wave potential(E_(1/2))of 0.911 V,a high four-electron process selectivity and excellent stability.The ORR performance is also verified in the Fe_(AC)/Cu_(SA)@NCS-based Zn-air battery,which shows a high peak power density of 192.67 mW cm^(-2),a higher specific capacity of 808.3 mAh g^(-1)and impressive charge-discharge cycle stability.Moreover,density functional theory calculations show that Cu single atoms synergistically modulate the electronic structure Fe active atoms in Fe atomic clusters,reducing the energy barrier of the rate-determining step(i.e.,*OH desorption)on Fe_(AC)/Cu_(SA)@NCS.This work provides an effective way to regulate the electronic structure of Fe-based catalysts and optimize their electrocatalytic activity based on the introduction of a second metal source.
基金Project supported by the National Key R&D Program of China(Grant Nos.2022YFA1402503,2023YFA1406200,2023YFB3003001)the National Natural Science Foundation of China(Grant Nos.12074138 and 12047530)+2 种基金the Interdisciplinary Integration and Innovation Project of JLUFundamental Research Funds for the Central Universitiesthe Program for JLU Science and Technology Innovative Research Team(JLUSTIRT)。
文摘High-mobility semiconductor nanotubes have demonstrated great potential for applications in high-speed transistors,single-charge detection,and memory devices.Here we systematically investigated the electronic properties of single-walled boron antimonide(BSb)nanotubes using first-principles calculations.We observed that rolling the hexagonal boron antimonide monolayer into armchair(ANT)and zigzag(ZNT)nanotubes induces compression and wrinkling effects,significantly modifying the band structures and carrier mobilities through band folding andπ^(*)-σ^(*)hybridization.As the chiral index increases,the band gap and carrier mobility of ANTs decrease monotonically,where electron mobility consistently exceeds hole mobility.In contrast,ZNTs exhibit a more complex trend:the band gap first increases and then decreases,and the carrier mobility displays oscillatory behavior.In particular,both ANTs and ZNTs could exhibit significantly higher carrier mobilities compared to hexagonal monolayer and zinc-blende BSb,reaching 10^(-3)-10^(-7) cm^(-2)·V^(-1)·s^(-1).Our findings highlight strong curvature-induced modifications in the electronic properties of single-walled BSb nanotubes,demonstrating the latter as a promising candidate for high-performance electronic devices.
基金supported by the National Natural Science Foundation of China(no.52363028,21965005)the Natural Science Foundation of Guangxi Province(2021GXNSFAA076001,2018GXNSFAA294077)the Guangxi Technology Base and Talent Subject(GUIKE AD23023004,GUIKE AD20297039).
文摘Triggering structural asymmetry can induce charge redistribution and modify electronic structures,which is of great significance for the design of high-performance hydrogen oxidation reaction(HOR)electrocatalysts.Herein,we propose a dual anion-induced strategy to create an innovative RuS_(2)-RuO_(2)heterostructure featuring abundant S-Ru-O interfaces(RuS_(2)-RuO_(2)@C).This RuS_(2)-RuO_(2)@C demonstrates an impressive mass activity of 2.61 mAμg_(RU)^(-1)and an exchange current density of 2.96 mA cm^(-2),surpassing Pt/C and other comparative samples by over 20 times.Durability assessments confirm the superior stability of RuS_(2)-RuO_(2)@C,with only minimal performance loss during operation.Density functional theory(DFT)calculations indicate that the asymmetric S-Ru-O configuration optimizes the interfacial electronic structure and shifts the d-band center closer to the Fermi level,effectively reducing the energy barrier of the rate-determining step(RDS)in the alkaline HOR process.Moreover,in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy(ATR-SEIRAS)characteristics disclose the formation of a substantial hydrogen bond network at the S-Ru-o interface,which aids in the desorption of H_(2)O_(ad)and facilitates the vital Volmer step in the HOR pathway.
文摘Photocatalytic synthesis of hydrogen peroxide(H_(2)O_(2))has emerged as a promising approach because of its simplicity and environmental benefits.However,significant challenges remain obstacles to their advancement,such as the rapid recombination of photogenerated charge carriers and sluggish surface redox reactions on nonmetallic organic catalysts.Metal-based organic catalysts with tunable electronic structures are considered ideal for exploring the mechanisms and structure-performance relationships in H_(2)O_(2) synthesis.This review summarizes the fundamental principles of photocatalytic H_(2)O_(2) synthesis via oxygen reduction and water oxidation reactions.Recent advancements in electronic structure tuning strategies for metal-based organic catalysts are critically examined,focusing on their impact on light absorption range,photogenerated carrier separation,O_(2) activation,and the selective generation of H_(2)O_(2).In addition,this review comprehensively evaluates the applications of sacrificial agents in photocatalytic reaction systems and offers insights into the future development of metal-based organic catalysts for H_(2)O_(2) photosynthesis.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.NSFC-12494590,NSFC-12174428,and NSFC-12274279)the New Cornerstone Investigator Programthe Chinese Academy of Sciences Project for Young Scientists in Basic Research(Grant No.2022YSBR-048).
文摘Determining the electronic structure of La_(3)Ni_(2)O_(7)is an essential step towards uncovering its superconducting mechanism.It is widely believed that the bilayer apical oxygens play an important role in the bilayer La_(3)Ni_(2)O_(7)electronic structure.Applying the hybrid exchange–correlation functionals,we obtain a more accurate electronic structure of La_(3)Ni_(2)O_(7)at its high-pressure phase,where the bonding dz2 band is below the Fermi level owing to the apical oxygen.The symmetry properties of this electronic structure and its corresponding tight-binding model are further analyzed.We find that the antisymmetric part is highly entangled,leading to a minimal nearly degenerate two-orbital model.Then,the apical oxygen vacancies effect is studied using the dynamical cluster approximation.This disorder effect strongly destroys the antisymmetric b Fermi surface,leading to the possible disappearance of superconductivity.
基金Project sponsored by the Natural Science Foundation of Chongqing,China(Grant No.CSTB2024NSCQMSX0736)the Special Project of Chongqing Technology Innovation and Application Development(Major Project)(Grant No.CSTB2024TIAD-STX0035)the Research Foundation of Institute for Advanced Sciences of CQUPT(Grant No.E011A2022328)。
文摘We theoretically investigate the electronic structure of cylindrical magnetic topological insulator quantum wires in MnBi_(2)Te_(4).Our study reveals the emergence of topological surface states in the ferromagnetic phase,characterized by spin-polarized subbands resulting from intrinsic magnetization.In the antiferromagnetic phase,we identify the coexistence of three distinct types of topological states,encompassing both surface states and central states.
基金supported by the National Natural Science Foundation of China(Grant No.12127804)the Supercomputing Center of University of Science and Technology of China.
文摘The binding energy spectra and electron momentum distributions(EMDs)of valence orbitals in toluene molecule were measured by(e,2e)electron momentum spectrometer.A comprehensive analysis of molecular vibrational effects on the EMDs was conducted through harmonic analytical quantum mechanical approach calculations and molecular dynamics simulations within the plane wave impulse approximation(PWIA).Furthermore,the multicenter three-distorted-wave method was employed to investigate the validity of the PWIA.A comparison between experimental measurements and theoretical predictions demonstrates that molecular vibrations have negligible effects on the EMDs,whereas the distorted-wave effects are obvious,particularly in large momentum regions.
基金Project supported by the National Natural Science Foundation of China(Grant No.12127804).
文摘We present a comprehensive electron momentum spectroscopy study on the electronic structure of trifluorobromomethane.The binding energy spectrum and electron momentum profiles of the entire outer-valence orbitals and the first inner-valence orbital along with several shake-up states were measured by using a high-sensitivity(e,2e)apparatus at an electron impact energy of 1213 eV.Theoretical calculations employing the density functional theory with B3LYP hybrid functional and the symmetry-adapted cluster configuration-interaction method were performed to interpret the experimental results.Important effects of electron correlations in the initial neutral and final ionic states on the electron momentum profiles have been observed.
基金financially supported by the National Key Research and Development Program of China(No.2019YFA0405601)the National Natural Science Foundation of China(No.52130202)the Scientific Research Foundation for High-level Talents of Anhui University of Science and Technology(No.2022yjrc105)。
文摘The rapidly growing electric cars and energy storage systems have extremely promoted the development of advanced lithium and sodium ion batteries and stimulated evolution of high-capacity cathodes.Li/Na-rich layered cathodes consisting cationic and anionic reactions as the most typical representative of high-capacity cathodes have shown its tremendous potential.However,there is a long way to go before commercialization because of unsatisfactory performances including large voltage hysteresis,voltage fade and poor cycle performance.Numerous investigations on redox mechanisms and engineering strategies have been performed from the point view of structure and made significant progress,which has been well reviewed.Meanwhile,the unacceptable issues are essentially correlated to the electronic configuration of anionic redox and its interaction with adjacent transition metal cations,which can be well depicted from electronic structure.However,the investigations on anionic reaction process in the viewpoint of electronic structure have been much less summarized.This review aims to compile the current knowledge of anionic redox from the point view of electronic structure,including configuration,origination,evolution,detection and coupling relationship with cationic redox.This work is attempted to inspire new perspectives and design approaches for the development of high-capacity cathodes.
文摘Single-atom catalysts are promising for H_(2)O_(2) photosynthesis from O_(2) and H_(2)O,but their efficiency is still limited by the ill-defined electronic structure.In this study,Co single-atoms with unique four planar N-coordination and one axial P-coordination(Co-N_(4)P_(1))are decorated on the lateral edges of nanorod-like crystalline g-C_(3)N_(4)(CCN)photocatalysts.Significantly,the electronic structures of central Co as active sites for O_(2) reduction reaction(ORR)and planar N-coordinator as active sites for H_(2)O oxidation reaction(WOR)in Co-N_(4)P_(1) can be well regulated by the synergetic effects of introducing axial P-coordinator,in contrast to the decorated Co single-atoms with only four planar N-coordination(Co-N_(4)).Specifically,directional photoelectron accumulation at central Co active sites,induced by an introduced midgap level in Co-N_(4)P_(1),mediates the ORR active sites from 4e–-ORR-selective terminal–NH_(2) sites to 2e–-ORR-selective Co sites,moreover,an elevated d-band center of Co 3d orbital strengthens ORR intermediate*OOH adsorption,thus jointly facilitating a highly selective and active 2e^(–)-ORR pathway to H_(2)O_(2) photosynthesis.Simultaneously,a downshifted p-band center of N_(2)p orbital in Co-N_(4)P_(1) weakens WOR intermediate*OH adsorption,thus enabling a preferable 2e^(–)-WOR pathway toward H_(2)O_(2) photosynthesis.Subsequently,Co-N_(4)P_(1) exhibits exceptional H_(2)O_(2) photosynthesis efficiency,reaching 295.6μmol g^(-1) h^(-1) with a remarkable solar-to-chemical conversion efficiency of 0.32%,which is 15 times that of Co-N_(4)(19.2μmol g^(-1) h^(-1))and 10 times higher than CCN(27.6μmol g^(-1) h^(-1)).This electronic structure modulation on single-atom catalysts offers a promising strategy for boosting the activity and selectivity of H_(2)O_(2) photosynthesis.
