Topological thermal transport offers a quantum route to regulate heat flow through Berry-curvature-driven responses. However, approaches for dynamically switchable control of such transport are lacking. Here, we propose an interlayer-sliding-driven dynamical evolution mechanism to control topological thermal transport in bilayer antiferromagnetic electron crystals, exemplified by ScI2. Sliding breaks spin group symmetry, generates ferroelectric polarization, and reshapes layer-resolved Berry curvature, resulting in strong modulation of anomalous Nernst and thermal Hall conductivities as signatures of topological phase transitions. Giant thermal Hall peaks and Hall plateaus emerge under sliding, demonstrating amplified topological heat transport response. Reversing the sliding direction switches spin splitting and transport polarity, enabling direct reading of stacking order and motion direction. Our work uncovers topological thermoelectric characteristics and superior transport performance in sliding systems, providing new insights for thermoelectric device design and applications.

The fast-charging capability has become a critical performance requirement for next-generation lithium-ion batteries (LIBs). Layered high-nickel transition metal oxides (LiNixCoyMn(1-x-y)O2, x ≥ 0.8) have emerged as the most promising candidates due to their high specific capacity and energy density toward fast-charging LIBs. However, their practical implementation under fast-charging conditions is severely hindered by sluggish Li+ diffusion kinetics and interfacial instability. While a high Ni content effectively boosts capacity, it inevitably compromises structural robustness and accelerates surface degradation. Conventional surface coating methods, which typically target secondary particles, often suffer from nonuniform coverage and incomplete interfacial protection. To overcome these bottlenecks, we propose a novel surface engineering strategy that electrochemically constructs a conformal fast-ion-conducting layer directly on the primary particles of Ni-rich cathodes. High-resolution transmission electron microscopy equiped with energy-dispersive X-ray spectroscopy combined with time-of-flight secondary ion mass spectrometry (ToF-SIMS) verify the conformal and homogeneous nanoscale Li2SeO4 coating on primary particles, while Galvanostatic Intermittent Titration technique and Density Functional Theory calculations collectively demonstrate its fast Li+-ion transport characteristics, featuring a migration barrier as low as 260 meV. This strategy significantly improves high-rate performance (180.6 mAh·g-1 at 10C) and cycling durability (94.2% capacity retention after 100 cycles). This work presents a versatile and scalable interfacial engineering approach for advancing fast-charging layered cathode materials.

Li-alloy anodes have emerged as promising alternatives to the Li metal for all-solid-state batteries (ASSBs) due to their ability to mitigate interfacial side reactions and suppress dendrite growth. However, Li-ion diffusion limitation at the alloy/electrolyte interface remains a challenge. Herein, we propose a work function-tunable Li–Ag alloy design to reduce the electrostatic barrier at the Li–Ag/β-Li3PS4 interface based on a first-principles-informed thermodynamic model. Our calculations show that among Li–Ag alloys, Li-rich phases Li3Ag and Li11Ag2 exhibit ultralow Li diffusion barriers (∼0.1 eV) and favorable Li vacancy formation energies, enabling rapid Li diffusion. Our analysis of work functions of Li–Ag alloys as functions of orientation and termination reveals that surface termination is the primary determinant, with orientation playing a secondary role. A Li-terminated surface substantially lowers the work function, thereby reducing the interfacial potential drop and promoting Li-ion transport. While the influence of orientation is comparatively minor, its optimization can further reduce the barrier. Notably, the Li3Ag phase with a Li-terminated (111) surface achieves an interfacial potential drop as low as 0.20 V, much lower than that of the Ag-terminated (111) surface. Our findings highlight surface termination as a critical design principle and suggest that synergistic optimization of alloy composition, termination, and orientation is essential to minimize interfacial barriers in ASSBs.

The interface structure of the electrode-electrolyte plays a crucial role in the electrochemical performance of sodium-ion batteries (SIBs). In this study, two black phosphorus-NaZr2(PO4)3heterojunctions (BP-NZP) with parallel stacking (PS) and vertical stacking (VS) configurations are constructed. The adsorption and diffusion behaviors of sodium (Na) at both BP-NZP heterojunctions are investigated by first-principles calculations. Binding energies indicate that both BP-NZP heterostructures are energetically stable, with the VS BP-NZP more stable. The PS BP-NZP has large interlayer barriers hindering ion diffusion into BP layers. While the VS BP-NZP contains wide channels with low barriers, which facilitate ion diffusion from interface into the BP. Furthermore, it is found that for the two BP-NZP heterostructures, Na atoms prefer to be adsorbed in the interfacial region, and these adsorptions have little effect on the dielectric properties of NZP and the electronic properties of BP, which is required for high-performance SIBs. The climbing image-nudged elastic band calculation and electrostatic potential distribution analysis further confirm that the wide channels in VS BP-NZP significantly improve Na migration from the interface into BP layers, whereas such migration of Na encounters greater difficulty in PS BP-NZP. In addition, our results show that trapping Na atoms at the interface of the VS BP-NZP can improve Na migration, which reveals that interface structure of electrode-electrolyte has a critical impact on the migration behavior of Na to traverse this interface. These findings suggest that an optimized heterostructure design strategy for the electrode-electrolyte can significantly improve the performance of SIBs.

Biphenylene network, a two-dimensional material, has recently been extensively studied, owing to its potential applications. Here, we introduce an experimentally synthesized configuration of hexagonal biphenylene network (h-BPN) as a second-order topological insulator (SOTI). We begin by discussing the higher-order topological origin of h-BPN, which is an extended model of the Kekulé lattice characterized by a multi-node π-conjugation. Through first-principles calculations and tight-binding model, we reveal SOTI in h-BPN, characterized by non-zero fractional corner charges. Furthermore, we show that by varying the number of biphenylene units, h-BPN exhibits adjustable second-order topological phases with alternating parity. Specifically, odd biphenylene indices in the h-BPN system correspond to a SOTI, while even indices result in a trivial insulator. We propose that the h-BPN evolves from the Kekulé lattice. These materials will have important applications in two-dimension devices as higher-order topological materials.

Recent progress in spintronics within the paradigm of altermagnets (AMs) opens new avenues for next-generation electronic device design. Here, we establish a spin-corner locking mechanism that generates second-order topological states in two-dimensional (2D) altermagnetic systems through effective model analysis. Remarkably, the breaking of Mxy symmetry under uniaxial strain creates spin-resolved corner modes, driving the system into a corner-polarized second-order topological insulator (CPSOTI). Beyond critical strain, a topological phase transition to a quantum anomalous Hall insulator occurs with quantized conductance. Through first-principles calculations, we identify two experimentally viable candidates for 2D intrinsic AM CrO and Cr2Se2O, which host robust CPSOTI. Moreover, we construct the topological phase diagram of CrO and predict the existence of an altermagnetic Weyl semimetal phase. Our findings open technological avenues in altermagnetism and higher order topology while providing opportunities for coupling topological spintronics with cornertronics.

Two-dimensional semiconductors have been identified as promising channel materials in nanoelectronic devices for sustaining Moore's law. Searching for suitable metal electrodes is critical to fabricating highperformance nanoscale channel field-effect transistors (FETs). In the present article, we adopt first-principles calculations to explore adsorption energy, adsorption structures, and electronic structures of H, Li, B, C, N, O, F, and Na adsorption on monolayer blue phosphorene (BlueP). Our calculated results indicate that all adatoms have minor impacts on the structure of BlueP except for B, C, and F adatoms. H, Li, Na, and N adsorption results in metallic properties of adsorption systems, but O adsorption preserves its semiconductor property. We also use density functional theory coupled with the nonequilibrium Green function method to investigate the transport properties of BlueP-based FETs with Li-adsorbed and Na-adsorbed BlueP electrodes. Our calculated results indicate that Li-adsorbed BlueP is superior to Na-adsorbed BlueP. Especially, BlueP-based FET with 9 nm channel length exhibits an excellent on-state current of approximate to 1540.3 mu A/mu m, distinctly exceeding the International Technology Roadmap for Semiconductors requirements for high-power devices. These results imply that Li-adsorbed BlueP may act as an appropriate electrode material for BlueP-based FETs, meaning that low contact resistance can be obtained by surface adsorption strategy. In addition, the results of carrier density, device conductance, projected density of states, and real-space scattering state show that O adsorption on BlueP channel can improve the electrical transport performance of the device. This implies that absorbing suitable elements on the semiconductor channel can effectively improve device performance, thus providing guidance for the design of future FETs.

Manipulating orbital angular momentum (OAM) offers significant opportunities for advancing orbitronics in quantum device applications. In this study, we investigate topological phase transitions in two-dimensional ferromagnetic higher-order topological insulators driven by electronic correlations. We reveal that these transitions are intrinsically linked to the orbital Hall effect (OHE) through valley degrees. During the phase transitions, the OAM remains valley locked, giving rise to distinct orbital valley Hall effects, which reflect the inherent connection between topological properties and orbital transport. Using first-principles calculations and tight-binding models, we identify FeBr2 as a representative system to illustrate the intrinsic correlation between the OHE and higher-order topology. Notably, the OHE exhibits unique signatures across different topological phases, highlighting the interplay of electronic correlations and valley physics. This work provides a robust framework for understanding the interplay between topological phases and orbital transport phenomena, paving the way for different applications in topological materials and orbitronics.

The kagome lattices of theATi3Bi5family have recently garnered significant attention due to their superconducting and topological properties. Here, we conducted an in-depth analysis of the band structure of the prototypical titanium-based kagome lattice material, CsTi3Bi5, using Density Functional Theory. We revealed its topological properties and demonstrated that the Van Hove singularities can be effectively tuned to the Fermi level under 18 GPa. Our findings confirm the dynamic stability of the CsTi3Bi5system and further demonstrate that its elastic constants, which comply with Born's criteria, ensure mechanical stability. The Poisson's ratio and Pugh's ratio indicate good ductility, while the material exhibits relatively low hardness. Notably, the mechanical properties exhibit significant directional anisotropy under all pressure conditions. As a key material in kagome lattices, the research results on CsTi3Bi5provide theoretical insights for experimental studies and the preparation of similar materials.

The high interfacial resistance between an electrode and a solid electrolyte remains a critical problem needed to be addressed for the practical application of all-solid-state batteries (ASSBs). While introducing an interlayer is a promising strategy to mitigate this resistance, the unclear action mechanism of the interlayer on the interfacial Li+ transport impedes further development. Herein, employing a first-principles-informed thermodynamic model, we demonstrate an effective approach for modulating the space-charge layers and electrostatic barriers for Li+ transport at the beta-Li3PS4/LixCoO2 interfaces by incorporating a LiAlO2 interlayer in Li/beta-Li3PS4/LixCoO2 ASSBs. The potential profile calculations reveal a high discharge barrier for Li-ion migration at the beta-Li3PS4/LiCoO2 cathode interface, hindering the discharge process. By contrast, at the beta-Li3PS4/LiAlO2/LiCoO2 interface, a lower interface potential drop is achieved to assist Li+ transport for fast discharging. Further analysis of the charge transfer and the band alignment reveals that the reduced interface potential drop stems from the synergistic effects of LiAlO2's Fermi level, chemical potential, and ionization potential. This work enhances the understanding of the interlayer's impact on interfacial Li+ transport and provides design principles for interlayer materials in ASSBs.

Direct regeneration of spent LiCoO2 in recycling field is regarded as a promising strategy to reduce production costs and alleviate the burden of metal pollution. Targeting the extensively studied high-voltage LiCoO2 electrode, the simultaneous achievement of restoring the spent LiCoO2 and upgrading the high-voltage stability of regenerated LiCoO2 poses a considerable challenge. Herein, based on a first-principles-informed thermodynamic study, a modulation strategy has been proposed by introducing Al doping during direct regeneration to enhance the high-voltage performance of regenerated LiCoO2. The calculated results reveal that, due to the sufficient Li vacancies in the spent LiCoO2, Al atoms can preferentially occupy the Li vacancies (denoted as AlV(Li)) rather than Co sites (denoted as AlCo) by synergistically regulating Co chemical potential and temperature. Inspiringly, the surface stability of regenerated LiCoO2 with AlV(Li) doping is significantly enhanced at high voltages. Furthermore, although both AlV(Li) and AlCo doping improve the electronic conductivity of regenerated LiCoO2, only the AlV(Li) doping exhibits an improvement of the Li+ diffusion kinetics. This innovative strategy provides a novel perspective for the efficient and high-quality recycling of the spent LiCoO2 in industrial applications.

Previous studies have demonstrated that La doping effectively restrains the formation of the CeFe2 in Cebased alloy systems, yet there is still a lack of clear explanation for its internal mechanisms. In this study, we calculated the structural stability, electronic structure, magnetic properties and elastic properties of CeFe2 doped with La based on first-principles. Results indicate that increasing La substitution elevates the formation energy, leading to thermodynamic destabilization. The weakening of the hybridization of Fe-3d and Ce-4f reveals a decrease in the electronic structure stability of the CeFe2 phase. Elastic parameter analysis confirms mechanical stability across all compositions, with LaFe2 showing the least robust stability. Therefore, this study reveals that La doping prevents the formation of CeFe2 by simultaneously disrupting its thermodynamic stability and electronic structure synergy.

Fermionic and bosonic localized states induced by geometric frustration in the kagome lattice provide a distinctive research platform for investigating emergent exotic quantum phenomena in strongly correlated systems. Here, we report the discovery of coexisting electronic and phononic flat bands induced by geometric frustration in a novel kagome superconductor XPd5 (X=Ca, Sr, Ba). The electronic flat band is located around the Fermi level and possesses a nontrivial topological invariant with Z2=1. Additionaly, we identify multiple van Hove singularities (vHS) arise from the kagome Pd d orbitals with distinct dispersion and sublattice features, including conventional, higher-order vHS and p-type, m-type vHS. Specifically, our investigation of the vibrational modes of the phononic flat band reveals that its formation originates from destructive interference between adjacent kagome lattice sites with antiphase vibrational modes. A spring-mass model of phonons is established to probe the physical mechanism of the phononic flat bands. Furthermore, the calculations of electron-phonon coupling in the XPd5 reveal superconducting ground states with critical temperatures (Tc) of 4.25 K, 2.75 K, and 3.35 K for CaPd5, SrPd5, and BaPd5, respectively. This work provides a promising platform to explore the Fermion-boson many-body interplay and superconducting states, while simultaneously establishing a novel analytical framework to elucidate the origin of phononic flat bands in quantum materials.

Two-dimensional (2D) semiconductors have been explored as potential channel materials in future nanoscale field-effect transistors (FETs). However, searching for suitable gate dielectric materials interfaced with 2D semiconductor channels and controlling their quality to guarantee efficient gate role are critical and challenging in the fabrication of high-performance nanoscale FETs. In the present article, we adopt first-principles calculations to explore the binding energies, band structures, and electronic properties of heterojunctions between monolayer blue phosphorene (BlueP) semiconductor and dielectrics, including BlueP-BN, BlueP-HfO2, BlueP-TiO2, and BlueP-CaF2. For the first time, we deeply investigate the electronic properties of BlueP-dielectric heterojunctions under perpendicular external electric fields. Our calculated results indicate that HfO2 thin layer and monolayer CaF2 dielectrics are appropriate as gate dielectrics for BlueP-based FETs, and furthermore, monolayer CaF2 is superior to HfO2. We also investigate the electronic properties of BlueP-HfO2 with interfacial O-vacancy and BlueP-CaF2 with interfacial F-vacancy, as well as hydrogen passivation to the F-vacancy of BlueP-CaF2. Our results indicate that the interfacial atomic vacancies of dielectric layer greatly deteriorate its dielectric properties and have great impacts on the electrical properties of the whole heterojunction. Fortunately, hydrogen passivation to F-vacancy of BlueP-CaF2 can effectively protect the semiconductor properties of BlueP and the dielectric properties of CaF2. This implies that hydrogen passivation strategy can improve the performance of 2D semiconductor-based nanoelectronic devices with CaF2 as a gate dielectric, thus providing guidance for the design and optimization of future nanoscale FETs.

Quantum anomalous Hall effect (QAHE) characterized by the presence of multiple non-dissipertive edge conduction channels has garnered substantial research interest owing to its applications in energy-conserving electronic devices. However, the observation is constrained by extremely low temperatures, which pose challenges for practical implementation. In the context, we delineate the interrelationship between the anomalous Nernst effect and the quantum anomalous Hall effect through Berry curvature in the Bi/FeBi2Te4 heterostructure. Initially, under the application of strain engineering, we achieve precise regulation of the high-Chern number within the Bi/FeBi2Te4 heterostructure. We observe that the Berry curvature of systems with different Chern numbers varies significantly. Consequently, in diverse systems, anomalous Nernst conductance (ANC) induced by Berry curvature also has obvious differences. Next, through first-principles calculation, we use ANC to characterize distinct quantum anomalous Hall insulators. Notably, at elevated temperature, we identify several ANC energy intervals with characterization properties near the Fermi level. Our results proffer a feasible approach for delineating the QAHE through detectable thermoelectric signals.

We propose ferroelectric layer sliding as a new approach to realize and manipulate topological quantum states in two-dimensional (2D) bilayer magnetic van der Waals materials. We show that stacking monolayer ferromagnetic topological states into layer-spin-locked bilayer antiferromagnetic structures, and introducing sliding ferroelectricity leads to asynchronous topological evolution of different layers (spins) owing to the existence of polarization potentials, thereby giving rise to rich layer-resolved topological phases. As a specific example, by means of a lattice model, we show that a bilayer magnetic 2D second order topological insulator (SOTI) reveals an unrecognized spin-hybrid-order topological insulator after undergoing ferroelectric sliding. Interestingly, in such a phase, the spin-up (top layer) and spin-down (bottom layer) channels exhibit first-order and second-order topological properties, respectively. Moreover, other topological phases such as the SOTI, quantum spin Hall insulator, quantum anomalous Hall insulator, and trivial insulator, can also emerge through changes in the parameters of the system; and the relevant topological indices are also discussed. In terms of materials, based on first principles calculations, we predict the material ScI2 can serve as an ideal platform to realize our proposal. Further, we predict that the anomalous Nernst effect of these several topological phases exhibits distinct differences, and therefore can be used as a signal for experimental probing.

Spin-gapless semiconductors (SGSs), as a new class of quantum materials, bridge conventional semiconductors and semi-metallic ferromagnets. Herein, the stability and topological properties of PbPdO2 with Bi substituting for Pb are systematically analyzed through first-principles calculations. The results show that Bi substitution for Pb is thermodynamically stable under Pb-poor conditions. Significantly, under the effect of spin-orbit coupling, the doped system demonstrates topological properties via topological order analysis, confirming its status as a topological material. Our results not only clarify the optimal growth conditions and topological nature of Pb0.5Bi0.5PdO2, but also reveal the inherent link between SGSs and non-trivial topological states, thereby offering a theoretical foundation for the design of innovative spintronic devices featuring efficient spin transport and topological protection.

Spin-gapless semiconductors (SGSs), as a new class of quantum materials, bridge conventional semiconductors and semi-metallic ferromagnets. Herein, the stability and topological properties of PbPdO2with Bi substituting for Pb are systematically analyzed through first-principles calculations. The results show that Bi substitution for Pb is thermodynamically stable under Pb-poor conditions. Significantly, under the effect of spin-orbit coupling, the doped system demonstrates topological properties via topological order analysis, confirming its status as a topological material. Our results not only clarify the optimal growth conditions and topological nature ofPb0.5Bi0.5PdO2, but also reveal the inherent link between SGSs and non-trivial topological states, thereby offering a theoretical foundation for the design of innovative spintronic devices featuring efficient spin transport and topological protection.

The inverse spin Hall effect is a critical method for detecting spin Hall conductivity. Unearthing the physical relationship between electronic structure and spin Hall conductivity is conducive to establishing an intrinsic link between microstructure and macroscopic phenomena. Here, we report MnBi2Te4 as an ideal candidate: a stable, inversion symmetry-broken magnetic topological insulator for investigating the intrinsic correlation between spin Hall conductivity signal reversal and electronic structure. The valence band exhibits a significant Rashba spin splitting, with a magnitude reaching up to 4.61 eV/Å. We identify robust topological properties independent of Rashba and Lifshitz spin-splitting types. Moreover, transitioning the spin-splitting type not only widens the bulk band gap, enhancing the spin Hall conductivity plateau, but also triples the intrinsic spin Hall conductivity value. We propose the inverse spin Hall effect that is tunable by spin-splitting types, thereby advancing the research on the microscopic electronic mechanisms of spin current detection. The spin Hall effect facilitates the generation and detection of spin currents and is expected to play an important role in future spintronic devices. Here, the authors theoretically investigate the presence of Rashba spin splitting for MnBi2Te4 and the relationship with an inverse spin Hall effect also present in the system.

The high interfacial resistance between an electrode and a solid electrolyte remains a critical problem needed to be addressed for the practical application of all-solid-state batteries (ASSBs). While introducing an interlayer is a promising strategy to mitigate this resistance, the unclear action mechanism of the interlayer on the interfacial Li+ transport impedes further development. Herein, employing a first-principles-informed thermodynamic model, we demonstrate an effective approach for modulating the space–charge layers and electrostatic barriers for Li+ transport at the β-Li3PS4/LixCoO2 interfaces by incorporating a LiAlO2 interlayer in Li/β-Li3PS4/LixCoO2 ASSBs. The potential profile calculations reveal a high discharge barrier for Li-ion migration at the β-Li3PS4/LiCoO2 cathode interface, hindering the discharge process. By contrast, at the β-Li3PS4/LiAlO2/LiCoO2 interface, a lower interface potential drop is achieved to assist Li+ transport for fast discharging. Further analysis of the charge transfer and the band alignment reveals that the reduced interface potential drop stems from the synergistic effects of LiAlO2's Fermi level, chemical potential, and ionization potential. This work enhances the understanding of the interlayer's impact on interfacial Li+ transport and provides design principles for interlayer materials in ASSBs.