Charge Redistribution Research Articles

Vacancy engineering in tungsten oxide nanofluidic membranes for high-efficiency light-driven ion transport.

Bioinspired light-driven ion transport has shown great potential in solar energy harvesting. To achieve efficiencies comparable to biological counterparts, effective coregulation of permselectivity and photoresponsivity is crucial. Herein, vacancy engineering has been proven to be a powerful strategy for considerably increasing the efficiency of light-driven ion transport in tungsten oxide (WO3-x) nanofluidic membranes by enhancing the negative surface charges and narrowing bandgaps. The enhancement in light-driven ion transport can be attributed to the efficient redistribution of surface charges due to the effective separation of photogenerated carriers. At an optimized vacancy concentration, WO2.66 membrane (WO2.66M) delivers an ionic photocurrent of 0.8μAcm-2 in a 10-4M KCl electrolyte, which is four times higher than that generated by the original WO2.85 membrane (WO2.85M). Following this strategy, uphill ion transport and photoenhanced osmotic energy conversion are successfully achieved in the WO3-x nanofluidic membrane system. This study shows that atomic vacancy engineering is an efficient approach to increase the light-driven ion transport dynamics of nanofluidics, providing an efficient strategy to enhance light-driven ion transport for potential applications in power harvesting and ion separation.

Strain-induced interstitial anionic electrons and superconductivity of monolayer BaCu

Abstract Recently, a novel electride, BaCu, which contains no light elements, has been both predicted and synthesized. This material adds to the list of inorganic two-dimensional (2D) interlayer electrides, including Ca2N and Y2C. However, the electride properties of the BaCu monolayer are not known, and its characteristics have not been thoroughly investigated. Here, our first-principles calculations indicated that the BaCu monolayer is a weak electride with few interstitial anionic electrons (IAEs). Notably, biaxial tensile strain can significantly alter the electronic properties of the BaCu monolayer, leading to the increase of IAEs. This strain causes a redistribution of charge from the Ba and Cu atoms to the IAEs. Additionally, the biaxial tensile strain induces superconductivity in the BaCu monolayer, and a notable increase in the critical superconducting transition temperature (Tc) to 0.2 K at 10% strain is observed. The coupling between the vibrations of the Cu atoms and IAEs plays a crucial role in this superconductivity. Our findings provide valuable insights into the relationship between the IAEs and superconductivity in the 2D electrides.

Phosphorus Regulates Coordination Number and Electronegativity of Cobalt Atomic Sites Triggering Efficient Photocatalytic Water Splitting.

Optimizing the local electronic structure of a single-atom catalyst (SAC) is crucial for efficient photocatalytic hydrogen evolution reactions. This study synthesized a Co-P4/g-C3N4 heterostructure by selective phosphidation of the Co metal-organic framework/graphitic carbon nitride (Co-MOF/g-C3N4), converting the Co-O6 configuration into a highly electronegative, coordinatively unsaturated Co-P4 configuration anchored to a carbon matrix. P-doping induces strong charge redistribution, shifting the d-band center toward the Fermi level, transforming the Co sites from an electron-deficient state to an electron-rich state, and resulting in a significant reduction in the free energy barrier for HER to -0.08 eV. The Co-P4/g-C3N4 heterostructure demonstrated a HER rate of 13.51 mmol g-1 h-1, approximately 4.82-8.35 times greater than those of photocatalysts loaded with noble metals. The apparent quantum efficiency (AQE) was 28.45% at 380 nm. The synergistic effect of the low coordination number and high electronegativity metal sites significantly enhances the photocatalytic HER performance.

Unexpected Magnetic Moments in Manganese-Doped (CdSe)13 Nanoclusters: Role of Ligands.

This study explores the enhancement in magnetic and photoluminescence properties of Mn2+-doped (CdSe)13 nanoclusters, significantly influenced by the introduction of paramagnetic centers through doping, facilitated by optimized precursor chemistry and precisely controlled surface ligand interactions. Using a cost-effective and scalable synthesis approach with elemental Se and NaBH4 (Se-NaBH4) in n-octylamine, we tailored bonding configurations (Cd-O, Cd-N, and Cd-Se) on the surface of nanoclusters, as confirmed by EXAFS analysis. These bonding configurations allowed for tunable Mn2+-doping with tetrahedral coordination, further stabilized by hydrogen-bonded acetate ligands, as evidenced by 13C NMR and IR spectroscopy. Mulliken charge analysis indicates that the charge redistribution on Se2- suggests electron transfer between surface ligands and the nanocluster, contributing to spin fluctuations. These tailored configurations markedly increased the nanoclusters' magnetic susceptibility and photoluminescence efficiency. The resulting nanoclusters demonstrated a clear concentration-dependent response in emission lifetimes and intensities upon exposure to magnetic field effects (MFE) and spin-spin coupling, alongside a large magnetic moment exceeding 40 μB at 180K. These findings highlight the potential of these nanoclusters for magneto-optical devices and spintronic applications, showcasing their tunable magnetic properties and exciton dynamics.

Unexpected Magnetic Moments in Manganese‐Doped (CdSe)13 Nanoclusters: Role of Ligands

This study explores the enhancement in magnetic and photoluminescence properties of Mn2+‐doped (CdSe)13 nanoclusters, significantly influenced by the introduction of paramagnetic centers through doping, facilitated by optimized precursor chemistry and precisely controlled surface ligand interactions. Using a cost‐effective and scalable synthesis approach with elemental Se and NaBH4 (Se‐NaBH4) in n‐octylamine, we tailored bonding configurations (Cd‐O, Cd‐N, and Cd‐Se) on the surface of nanoclusters, as confirmed by EXAFS analysis. These bonding configurations allowed for tunable Mn2+‐doping with tetrahedral coordination, further stabilized by hydrogen‐bonded acetate ligands, as evidenced by 13C NMR and IR spectroscopy. Mulliken charge analysis indicates that the charge redistribution on Se2‐ suggests electron transfer between surface ligands and the nanocluster, contributing to spin fluctuations. These tailored configurations markedly increased the nanoclusters' magnetic susceptibility and photoluminescence efficiency. The resulting nanoclusters demonstrated a clear concentration‐dependent response in emission lifetimes and intensities upon exposure to magnetic field effects (MFE) and spin‐spin coupling, alongside a large magnetic moment exceeding 40 μB at 180K. These findings highlight the potential of these nanoclusters for magneto‐optical devices and spintronic applications, showcasing their tunable magnetic properties and exciton dynamics.

Modulated Fe Central Spin State in FeCu4 Alloy Nanoparticles for Efficient and Selective Activation of H2O2

AbstractIn advanced oxidation processes, the efficient activation of H2O2 and the selective production of reactive oxygen species are the key steps to achieve the removal of organic pollutants in the water environment. Studies have shown that the precise regulation of catalyst metal active sites can break through the limitation of H2O2 activation and realize the efficient selective conversion of H2O2. Therefore, FeCu bimetallic active sites are developed by constructing FeCu4 alloy nanocluster metal catalyst (FeCu/NC). The introduction of Cu metal sites realized charge redistribution, promoted rapid electron transfer, reduced the spin state of Fe in the catalyst, diminished the interaction between Fe and O, weakened the strong and persistent adsorption between Fe center and *H2O2, lowered the energy barrier of intermediate products in hydroxyl radicals (·OH) generation process, achieved efficient activation of H2O2 and selective generation of ·OH. In addition, a complete electron circulation path is formed between FeCu active sites and the substrate, breaking the contradiction between single metal and H2O2 redox relationship, promoting efficient reduction of Fe3+ to Fe2+. The first‐order kinetic constant (kobs) of FeCu/NC is 0.081 min−1, which is 3.68 and 7.36 times higher than those of single Fe metal species (FeFe/NC) and single Cu metal species (CuCu/NC) catalysts, respectively, and has excellent catalytic performance).

Novel Ru‐O3Se4 Single Atoms Regulate the Charge Redistribution at Ni3Se2/FeSe2 Interface for Improved Overall Water Splitting in Alkaline Media

AbstractDeveloping low‐cost, highly active, and stable bifunctional catalysts is of great significance for electrochemical water splitting. Herein, novel Ru‐O3Se4 single atoms doped Ni3Se2/FeSe2 interface catalyst is fabricated by a two‐step method for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Notably, Ru‐Ni3Se2/FeSe2 nanosheets exhibit excellent HER (43 mV@10 mA cm−2) and OER (283 mV@100 mA cm−2) activities in alkaline solution. In particular, the mass activity of Ru‐Ni3Se2/FeSe2 catalyst is 3593.61 mA mg Ru−1 at 200 mV for HER and 7073.80 mA mgRu−1 at 400 mV for OER, which is 25.91 and 367.28 times of commercial Pt/C and RuO2, respectively. In situ spectroscopy techniques confirm Ru‐O3Se4 single atoms facilitate the adsorption of intermediates H* and OOH* during HER and OER processes, respectively. Further density functional theory calculations reveal introducing Ru‐O3Se4 single atoms causes the transfer of electrons from Ru to Ni and Fe atoms, leading to a redistribution of charge at the Ni3Se2/FeSe2 interface, thus reducing the energy barriers of rate‐determining step to −0.37 and 1.92 eV for HER and OER, respectively. This work emphasizes the significant role of single atoms at the interface for overall water splitting.

Molecular-level Modulation of N, S-Co-Doped Mesoporous Carbon Nanospheres for Selective Aqueous Catalytic Oxidation of Ethylbenzene.

Selective oxidation of aromatic alkanes into high value-added products through benzylic C-H bond activation is one of the main reactions in chemical industry. On account of the constantly increasing demand for mass production, efficient, eco-friendly and sustainable catalysts are urgently needed. Herein, we describe a facile and versatile emulsion-assisted interface self-assembly strategy towards molecular-level fabrication of co-doped mesoporous carbon nanospheres with controllable active N and S species. The method enables a high degree of control over nanoparticle sizes, mesoporous nanostructures, contents of heteroatoms and the chemical composition. The optimized catalyst exhibits high catalytic performance of 97 % ethylbenzene conversion and 98 % selectivity to acetophenone. Density functional theory simulations reveal that N, S-co-doping leads to the redistribution of charge and spin densities, introducing more active carbon atoms and realizing aerobic oxidation of ethylbenzene efficiently. This work presents a general strategy for molecular-level design of carbon-based catalysts, and also provides new insight into the influence of heteroatom-doping on catalytic properties.

Mapping of Internal Ionic/Electronic Transient Dynamics in Current-Voltage Operation of Perovskite Solar Cells.

Metal halide perovskites are mixed ionic-electronic semiconductors that involve an important and particular phenomenology that negatively affects the performance and stability of next-generation photovoltaic devices based on such material. The ionic nature of perovskites is shown to undergo not only a simple redistribution of charges but also influences the electronic processes and ultimately the steady-state device operation. Nevertheless, a comprehensive understanding of the internal contributions of ionic and electronic conductivities to the evolution of current during device performance experiments and to degradation losses in ageing tests is currently missing. Here the ionic- and electronic-based currents are separately shown in photovoltaic perovskites by means of transient experiments, beyond the external measured response. From an advanced mathematical model, the experimental observations attributing the partial transient features to physical effects in perovskites are rationalized. It is revealed that ion-driven surface recombination effects are a dominant factor in the slowdown of efficiency measurements and in the long-term degradation of perovskites under operational conditions. This work contributes to tracing a more accurate physical picture of the complex energy landscape of the perovskite-based solar cells, which will be key to taking steps toward industrialization.

Defect Engineering Enhancing Piezoelectric Catalytic Activity of Covalent Organic Framework Matrix Composites for Uranium Removal.

Piezoelectric catalysis is an emerging green strategy, but the existing piezoelectric heterostructures are not sufficient in performance for catalytic reduction of low-reduction potential uranium under harsh conditions. This study innovatively employs a defect heterogeneous engineering strategy, wherein covalent organic frameworks (COFs) are grown in situ on the surface of zinc oxide (ZnO) via Schiff base reactions, and defects are introduced into the COF shell layer via imine exchange reactions to construct D-COF@ZnO for piezoelectric catalytic uranium removal. The comprehensive study shows that defect heterogeneous engineering increases the asymmetry induced polarization of the material to promote charge redistribution, and thus significantly improves the activity of piezoelectric catalysis. In addition, defect engineering optimizes the nanosize of D-COF@ZnO to expose a richer array of active sites, resulting in ultra-fast U(VI) removal kinetics and ultra-high removal capacity. In the actual nuclear wastewater settings, D-COF@ZnO demonstrates outstanding selective removal efficacy for uranium, manifesting its considerable application potential and efficiency superiority. This strategy holds profound implications for facilitating the application of piezoelectric catalytic technology in environmental protection domains such as uranium removal, manifesting its considerable potential and value.

Unveiling spin magnetic effect of TM doped SnS2 nanosheet with enhanced hydrogen evolution reaction

Photoelectrochemical hydrogen evolution reaction (HER) is taken into account as an alternative to effective hydrogen production, emphasizing the importance of catalysts. The magnetism of catalysts could modulate the adsorption of the H atom and further enhance the HER activity. Herein, doping the double transition metal atoms on SnS2 nanosheet (TM2@SnS2) to form the efficient magnetic catalyst is proposed to explore the spin magnetic effect on the HER performance. By performing first-principles calculations, nonmagnetic V2@SnS2 is proved to be the candidate of the HER catalyst; nevertheless, the HER activities of antiferromagnetic and ferromagnetic V2@SnS2 are relatively inferior due to the spin-induced charge redistribution. Meanwhile, machine learning analysis shows the absolute importance of the electronic structure of TM dopants and surrounding S ligands, and the HER activity could be predicted by the modified band centers of S-3pz and TM-d. Furthermore, the proof-of-concept experiment has substantiated the above theoretical predictions by significantly increasing photocurrent with applied magnetic field. This work provides a new avenue for uncovering the spin catalytic mechanism and the exploration and design of efficient HER catalysts.

Anion Doping as a “Trigger” to Modulate Defect‐Tailored Dielectric Coupling for Ultrathin Microwave Absorber

AbstractAnion doping engineering is recognized as a prospective strategy to adjust the electronic configuration and transport capacity of carbon‐based magnetoelectric hybrids and to optimize defects for the modulation of electromagnetic (EM) properties. This study effectively accomplishes an overwhelming enhancement in the dielectric coupling between conduction and polarization for the CuCo bimetallic/carbon system by employing in situ (N, O)/ex situ (S, Se) doping and defect modulation strategies. The well‐designed lattice distortions are facilitated by the large atomic radii (Se) intercalated carbon skeleton and the bimetallic CuCo, which activate the reinforcement of the dipole polarization in the high‐frequency region. Interestingly, an appropriate number of vacancies acts as “electron traps” to accelerate the local charge redistribution, endowing the system with extremely strong electronic interactions and interface‐induced polarization. It is remarkable that the ultra‐thin feature (1.8 mm) is able to achieve an extraordinary microwave attenuation (‒56.1 dB). Additionally, specific defect upgrading of anionic Se doping beneficially hinders the development of phonon transmission, conferring Cu2Se/CoSe2/NC‐Se aerogel outstanding infrared stealth capabilities along with inheriting the advantages of traditional carbon‐based hybrids (lightness, compressive/structural stability, and hydrophobicity/anti‐corrosive properties). This research offers distinctive perspectives on the advanced design of multifunctional absorbers in complex environments.

High-Density Dual Atoms Pairs Coupling for Efficient Electromagnetic Wave Absorbers.

Dual atoms (DAs), characterized by flexible structural tunability and high atomic utilization, hold significant promise for atom-level coordination engineering. However, the rational design with high-density heterogeneous DAs pairs to promote electromagnetic wave (EMW) absorption performance remains a challenge. In this study, high-density Ni─Cu pairs coupled DAs absorbers are precisely constructed on a nitrogen-rich carbon substrate, achieving an impressive metal loading amount of 4.74wt.%, enabling a huge enhancement of the effective absorption bandwidth (EAB) of EMW from 0 to 7.8GHz. Furthermore, the minimum reflection loss (RLmin) is -70.96dB at a matching thickness of 3.60mm, corresponding to an absorption of >99.99% of the incident energy. Both experimental results and theoretical calculations indicate that the synergistic effect of coupled Ni─Cu pairs DAs sites results in the transfer of electron-rich sites from the initial N sites to the Cu sites, which induces a strong asymmetric polarization loss by this redistribution of local charge and significantly improves the EMW absorption performance. This work not only provides a strategy for the preparation of high-density DA pairs but also demonstrates the role of coupled DA pairs in precisely tuning coordination symmetry at the atomic level.

Precisely Engineering of Ångström‐Scale Dual Single Atom Drive [Co‐O] Spin‐Orbit Coupling to Boost Lithium–Oxygen Batteries Electrocatalysis

AbstractDual‐atom catalysts (DACs) have emerged as a novel area of investigation in lithium–oxygen (Li‐O2) batteries due to their distinctive synergistic mechanisms. However, achieving precise control of the active site structure and unraveling the synergistic effects of bimetallic species remains a significant challenge. Here, the study reports a pre‐encapsulated pyrolysis strategy using a Co‐based Robson‐type binuclear complex as a precursor to mediate the synthesis of dual single‐atom Co (Co‐DAC) with precise angstrom‐scale inter‐site distance configuration, serving as an efficient catalyst for Li‐O2 batteries. The tailored structure induces significant charge redistribution, reducing crystal field splitting energy (ΔO). The high‐spin Co species generate a strong electronic driving force, forming flexible σ and δ‐like bonds with the crucial oxygen intermediate (*O). Simultaneously, enhanced Co‐O spin‐orbit coupling facilitates electron transport along the bridging O‐channel, forming highly active Co‐O‐O‐Co electron chains that synergistically adsorb *O, establishing a favorable reaction pathway. Significant optimization of Li‐O2 batteries redox kinetics is achieved based on the well‐defined local structure of dual single‐atom Co sites. This work enhances the understanding of the dependence between rational design of custom structures and corresponding electron transfer dynamics, while providing new strategies and theoretical guidance for DACs to help develop high‐performance Li‐O2 batteries.

Removal of hydrogen by electric and polarized fields for high-performance AlGaN deep-ultraviolet-C light emitting diodes

The dehydrogenation of the Mg–H complex to increase the hole concentration is crucial for promoting the performance of ultraviolet-C light-emitting diodes (UVC-LEDs). Here, we systematically investigate the efficient removal of H atoms through combining external electric field produced by electrochemical process and polarized electric field of p-AlGaN. The measured electroluminescence spectra show the emission intensity of optimized AlGaN structure achieving a large increment of 12.5% after the H removal. Furthermore, the reliability and lifetime of UVC-LEDs are also significantly promoted by our methods. The physical mechanism of the coupling interaction between external and polarized electric fields on H removal is further elucidated through the first-principles calculations. The density of states, electrostatic potential energies, and differential charge densities of Mg–H doping AlGaN under various electric fields reveal that the charge redistributions and huge electrostatic potential difference between Mg and H atoms are responsible for the breaking of Mg–H bonds and expelling of H atoms. This work offers feasible strategy to promote the applications of AlGaN-based UVC-LEDs.

Enhancing photocatalytic performance in Bi₂WO₆ nanolayers via ultrasound-assisted oxygen vacancy engineering

High-quality two-dimensional Bi₂WO₆ nanolayers were synthesized via hydrothermal processes, with oxygen vacancies introduced through an ultrasound-assisted alkali etching treatment. Comprehensive characterization using Raman spectroscopy, X-ray absorption spectroscopy (XAS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and positron annihilation spectroscopy (PAS) confirmed the presence and effects of these vacancies on the structural and electronic properties of the nanolayers. Raman spectroscopy revealed shifts in vibrational modes, particularly a blue shift in the WO₆ octahedral vibration modes, indicative of oxygen vacancy formation. XPS analysis showed a reduction in the binding energies of the Bi 4f and W 4f orbitals, confirming an altered electronic environment. TEM images demonstrated significant lattice distortions in the oxygen-vacancy-rich regions, particularly disordered WO₆ octahedra and disrupted BiO bond lengths. These distortions are consistent with the structural disorder observed in XAS measurements, which highlighted a reduction in the coordination number of W atoms and a corresponding contraction of WO bond lengths. This charge redistribution between Bi and W atoms due to oxygen vacancies leads to localized structural perturbations, as further evidenced by PAS, which showed increased positron lifetimes associated with vacancy clusters, particularly around the Bi and W atoms. These vacancies create defective sites that trap photogenerated electrons, preventing their recombination with holes, thereby significantly enhancing photocatalytic performance. The enhanced photocatalytic activity was demonstrated by the nearly 98 % degradation of Rhodamine B dye under visible-light irradiation, a substantial improvement over the 70 % degradation achieved by the untreated sample. This work presents an innovative approach for generating stable oxygen vacancies in Bi₂WO₆ nanolayers and offers an in-depth understanding of the mechanisms that enhance photocatalytic performance, providing valuable insights for advancing photocatalysts designed for environmental remediation.

Manipulating interfacial charge redistribution in Mott-Schottky electrocatalyst for high-performance water/seawater splitting

Interface engineering is an effective approach towards developing low-cost highly efficientelectrocatalystsforgreen hydrogen productionin alkaline water or seawater environments. Herein, we have successfully fabricatedan interface engineered Mott-Schottky heterostructure catalyst i.e.,Fe3O4@Ni3S2, in which, Ni3S2 nanosheets are evenly dispersed on the surface of Fe3O4 flower-like nanosheets, which are supported by a Ni foam substrate. Due to the synergistic effect between Ni3S2 and Fe3O4, theFe3O4@Ni3S2 heterostructure catalystdemonstrates remarkable catalytic activity under alkaline conditions whichis attributed to thehighlyexposed active sites, adjustment of the d-band center, and the built-in electric field at the interface. The catalyst Fe3O4@Ni3S2 has low overpotentials of 207 and 217 mV for the OER (oxygen evolution reaction) and 99 and 118 mV for the HER (hydrogen evolution reaction) in alkaline and seawater electrolytes, respectively, allowing it to yield a current density of 10 mA cm−2. Furthermore, the Fe3O4@Ni3S2||Fe3O4@Ni3S2 electrolyzer can achieve a current density of 10 mA cm−2 for alkaline fresh water and seawater (1 M KOH + seawater) electrolysis at low voltages of 1.57 V and 1.58 V, respectively. This study presents a novel approach for fabricating high-performance multi-interface 3D catalysts for overall water/seawater splitting.

Specific Adsorption of Alkaline Cations Enhances CO-CO Coupling in CO2 Electroreduction.

Electrolyte alkaline cations can significantly modulate the reaction selectivity of electrochemical CO2 reduction (eCO2R), enhancing the yield of the valuable multicarbon (C2+) chemical feedstocks. However, the mechanism underlying this cation effect on the C-C coupling remains unclear. Herein, by performing constant-potential AIMD simulations, we studied the dynamic behavior of interfacial K+ ions over Cu surfaces during C-C coupling and the origin of the cation effect. We showed that the specific adsorption of K+ readily occurs at the surface sites adjacent to the *CO intermediates on the Cu surfaces. Furthermore, this specific adsorption of K+ during *CO-*CO coupling is more important than quasi-specific adsorption for enhancing coupling kinetics, reducing the coupling barriers by approximately 0.20 eV. Electronic structure analysis revealed that charge redistribution occurs between the specifically adsorbed K+, *CO, and Cu sites, and this can account for the reduced barriers. In addition, we identified excellent *CO-*CO coupling selectivity on Cu(100) with K+ ions. Experimental results show that suppressing surface K+-specific adsorption using the surfactant cetyltrimethylammonium bromide (CTAB) significantly decreases the Faradaic efficiency for C2 products from 41.1% to 4.3%, consistent with our computational findings. This study provides crucial insights for improving the selectivity toward C2+ products by rationally tuning interfacial cation adsorption during eCO2R. Specifically, C-C coupling can be enhanced by promoting K+-specific adsorption, for example, by confining K+ within a coated layer or using pulsed negative potentials.

Anisotropic magnetoelectric effect in quasi-one-dimensional antiferromagnet Cu3Mo2O9

Using purely electrical methods to manipulate magnetic property poses a significant obstacle in the development of advanced information technology. Multiferroic materials, distinguished by their magnetoelectric (ME) effect, offer a promising way to overcome this challenge by enabling the electric control of magnetic ordering or magnetization. Here, we have synthesized Cu3Mo2O9 single crystals and investigated the anisotropic ME effect within the quasi-one-dimensional spin system. The simultaneous occurrence of ferroelectric (FE) polarization and dielectric anomaly at the Néel temperature (TN) of ∼7.9 K suggests the presence of spin-driven FE property in Cu3Mo2O9. The phase transition temperatures undergo a shift toward lower values for H//c and remain constant for H//a and H//b, indicating anisotropic ME effect. The ME effect demonstrates nonlinear behavior as the magnetic field increases. Near a critical point (T = 7 K and μ0H = 5.6 T), a giant magnetodielectric coupling parameter reaching 374% is observed for H//c, which can be ascribed to the strong spin–phonon coupling and the magnetic field induced change of FE polarization. In the context of charge redistribution without magnetic superlattice, the FE property is analyzed. Moreover, remarkable magnetic control of FE polarization and electric control of magnetization are obtained. The temporal evolution of both polarization and magnetization indicates the stable ME mutual control, suggesting potential applications of Cu3Mo2O9 as a promising multiferroic material.

Customizing Bonding Affinity with Multi‐Intermediates via Interfacial Electron Capture to Boost Hydrogen Evolution in Alkaline Water Electrolysis

AbstractDeveloping efficient and earth‐abundant alkaline HER electrocatalysts is pivotal for sustainable energy, but co‐regulating its intricate multi‐step process, encompassing water dissociation, OH− desorption, and hydrogen generation, is still a great challenge. Herein, we tackle these obstacles by fabricating a vertically integrated electrode featuring a nanosheet array with prominent dual‐nitride metallic heterostructures characterized by impeccable lattice matching and excellent conductivity, functioning as a multi‐purpose catalyst to fine‐tune the bonding affinity with alkaline HER intermediates. Detailed structural characterization and theoretical calculation elucidate that charge redistribution at the heterointerface reduces the O p‐W d and H s‐W d interactions vs. single nitride, thereby enhancing OH− transfer and H2 release. As anticipated, the resulting WN‐NiN/CFP catalyst demonstrates a gratifying low overpotential of 36.8 mV at 10 mA/cm2 for alkaline HER, while concurrently maintaining operational stability for 1300 h at 100 mA/cm2 for overall water splitting. This work presents an effective approach to meticulously optimize multiple site‐intermediate interactions in alkaline HER, laying the foundation for efficient energy conversion.