MXenes exhibit interesting structural and physicochemical properties, enabling them to be applied in a wide range of fields, including energy storage and electromagnetic shielding. However, conventional etching synthesis routes, such as hydrofluoric acid etching, Lewis-acid etching and molten-salt etching, are limited by long reaction times, high energy consumption and severe chemical hazards. Here we developed a rapid, scalable and reduced environmental impact approach for MXenes synthesis via sequential flash Joule heating-chlorination and fluorination. By precisely tuning the thermodynamic and kinetic parameters, diverse high-quality layered MXenes with excellent electrochemical performance were synthesized through the selective removal of interstitial atoms from nine different MAX phases, each within 30 s. Computational simulations elucidate the selective-etching mechanism, while high-resolution transmission electron microscopy captures atomic-scale structural evolution from MAX phase to MXene. This universal FJH-ClF strategy reduces energy and reagent usage, establishing a safe, cost-effective and sustainable method for next-generation MXene manufacturing. Flash Joule heating converts MAX phases into MXenes within tens of seconds through sequential chlorination and fluorination. By selectively removing A-layer atoms with reduced acid use, energy input and chemical waste, this approach offers a faster and more sustainable route to diverse MXenes.

Understanding surface-defect reactivity in ammonium perchlorate (AP) is essential for describing its reactivity. Using density functional theory, we compare sublimation pathways from pristine AP(001), and use density-functional tight binding for step edges, kinks, corners, and screw dislocations. Several proton-transfer pathways on flat AP(001) are close in energy, reflecting the complexity of the molecular-ionic crystal. Free-energy calculations show that kink defects lower the proton-transfer barrier by nearly a factor of 5 relative to the flat surface, with NH3 having lower activation energy than HClO4, and migrating to terraces. This indicates the possibility of intermediate stages that may limit the sublimation rate. A one-component kinetic model shows that kink density controls the regime: low kink density gives detachment-limited rates, whereas high kink density gives concentration-independent rates controlled by detachment and terrace desorption. Comparison with experiments highlights the role of surface morphology in AP reactivity.

MXenes exhibit exceptional structural and physicochemical properties, enabling them to be applied in a wide range of fields, including energy storage and electromagnetic shielding. However, conventional etching synthesis routes, such as hydrofluoric acid (HF) etching, Lewis acid etching, and molten-salt etching, are limited by long reaction times, high energy consumption, and severe chemical hazards. Here, we developed a rapid, scalable, and environmentally benign approach for MXene synthesis via sequential flash Joule heating-chlorination and fluorination (FJH-ClF). By precisely tuning the thermodynamic and kinetic parameters, diverse high-quality layered MXenes with excellent electrochemical performance were synthesized through the selective removal of interstitial atoms from nine different MAX phases, each within 30 s. This universal FJH-ClF strategy drastically reduces energy and reagent usage, establishing a safe, cost-effective, and sustainable method for next-generation MXene manufacturing.

Phase-selective chemical vapor deposition synthesis of two-dimensional (2D) transition-metal chalcogenides (TMCs) has garnered broad interest, yet its crucial dependence on the growth atmosphere is not understood. The chain of reactions transforming precursors into 2D crystals remains elusive. Focusing on iron telluride-a promising material for quantum and spintronic devices due to its phase-dependent topological superconductivity and magnetism-our first-principles calculation elucidates the phase-selective growth of tetragonal FeTe (t-FeTe), including its thermodynamic and kinetic shapes. We identify the FeTe4Cl as the immediate precursor-a molecule reacting directly at the edge of the expanding crystal. Due to the stoichiometric mismatch of this gaseous precursor and the product-crystal, the growth mechanism through kink propagation requires an additional step-the edge cleaning, eliminating excess atoms after FeTe4Cl attachment. Based on this, we further demonstrate that the experimental levers, namely Te-limited condition and H2 supply, enable edge cleaning, thereby promoting nanosheet lateral, in-plane expansion and high t-FeTe phase purity. Conversely, in a Te-rich environment, off-plane nuclei become favored, biasing nucleation toward nonlayered phase (hexagonal h-FeTe). This work explains how the experimental atmosphere affects growth dynamics of t-FeTe and provides valuable guidelines for optimizing synthesis parameters of other TMCs.

Physical entropy-driven true random number generators are essential for emerging probabilistic computing paradigms, but conventional implementations based on magnetic tunneling junctions have reached their performance plateaus limited by inherent tradeoffs and weak tunability. Here, autferroics, a sister branch of multiferroics, is proposed to construct true random number generators. Benefiting from its unique energy landscape due to strong seesaw-type magnetoelectricity, the performance of true random number generation can be significantly enhanced in autferroic tunneling junctions, verified by passing standard statistical tests. Furthermore, autferroics-based random number generators can exhibit multi-field tunability and intrinsic multi-state randomness, opening an avenue for efficient hardware realization of the complex-number arithmetic and simulation of probability distributions of quantum mixed states within stochastic circuits.

Intrinsic lattice vibrations are conventionally regarded as merely a thermal perturbation in photocatalysis, leaving their potential as an active control parameter largely unexplored. Here, we demonstrate that selectively activated intrinsic phonon modes can act as an internal driving force to dynamically regulate photocatalytic functionality. Using first-principles calculations on a Janus MoSSe/WSSe van der Waals heterostructure, we reveal that mode-selective lattice vibrations profoundly reshape the electronic structure and photocarrier transfer pathways. In particular, high-frequency intralayer phonon modes induce pronounced bandgap renormalization and trigger a qualitative transition in charge-transfer behavior, enabling a shift from conventional type-II separation toward an S-scheme-like catalytic regime. This phonon-driven electronic reconstruction optimizes metal d-band characteristics and metal–adsorbate interactions, thereby enhancing the catalytic activity for both hydrogen and oxygen evolution reactions. Our results uncover a direct, symmetry- and mode-dependent coupling between lattice vibrations and catalytic activity, establishing targeted phonon excitation as a promising and physically transparent strategy for activating high-performance photocatalysis beyond static structural design.

Electromagnetic response is commonly computed in two languages: length-gauge molecular polarizabilities and velocity-gauge (Kubo) conductivities for periodic solids. We introduce a compact, gauge-invariant bridge that carries the same microscopic inputs-transition dipoles and interaction kernels-from molecules to crystals and heterogeneous media, with explicit SI prefactors and fine-structure scaling via (α_ fs). The long-wavelength limit is handled through a reduced dielectric matrix that retains local-field mixing, interfaces and 2D layers are treated with sheet boundary conditions (rather than naïve ultrathin films), and length-velocity equivalence is enforced in practice by including the equal-time (diamagnetic/contact) term alongside the paramagnetic current. Finite temperature is addressed on the Matsubara axis with numerically stable real-axis evaluation (complex polarization propagator), preserving unit consistency end-to-end. The framework enables predictive, unit-faithful observables from radio frequency to ultraviolet-RF/microwave heating and penetration depth, dielectric-logging contrast, interfacial optics of thin films and 2D sheets, and adsorption metrics via imaginary-axis polarizabilities. Numerical checks (gauge overlay and optical (f)-sum saturation) validate the implementation. Immediate priorities include compact, temperature- and salinity-aware kernels with quantified uncertainties and operando interfacial diagnostics for integration into multiphysics digital twins.

The atomistic understanding of flash sintering (FS) remains speculative, despite its efficiency and versatility in materials processing. Employing first-principles calculations we demonstrate how charge compensation of a range of defects in the prototypical Y-stabilized cubic ZrO$_2$ (YSZ) shifts Fermi level E$_F$ up during FS, thereby accelerating cation migration for fast mass transport. The charge transition of Zr vacancy, V$_{Zr}^q$, reduces its bulk diffusion barrier in V$_{Zr}^{-4}$ during flash by 2 eV, relative to V$_{Zr}^0$ before flash, which is triggered by the charge equilibrium of nonstoichiometric defects. The substituent defect Y$_{Zr}$, released by annihilating O vacancy, V$_O$, in Y$_{Zr}$V$_O$Y$_{Zr}$ defect complex, acts as electron acceptor and favors V$_{Zr}^0$ before flash whereas excess V$_O$, as electron donor thermally generated at the FS onset, upshift E$_F$ and thus support V$_{Zr}^{-4}$. The proposed mechanism of Fermi-level mediated cation diffusion for YSZ is generalized to other flash-sintered ceramics and has considerable bearing on the general theory of FS techniques in oxide ceramics.

Transition-metal dichalcogenide (TMD) monolayers exhibit unique electronic, photonic, and quantum phenomena, yet their material quality remains constrained by defects and thickness inhomogeneity during chemical vapor deposition. Here, we identify the limitations of the common metal trioxide precursors: high volatility that induces stochastic vapor-phase nucleation and multilayer growth, and liberated oxygen-species-mediated chemical etchants that degrade lattice integrity. We demonstrate that an acid-mediated one-step modification, dissolving trioxides in hydrochloric acid, fundamentally redirects the precursor chemistry toward nonvolatile and substrate-anchored dioxide phase. This enforces a spatially confined solid-phase chalcogenization (SPC), minimizing the vapor-phase species and thereby suppressing dechalcogenization and vertical growth. The resulting uniform monolayers, synthesized as isolated triangular flakes or continuous films, achieve state-of-the-art low defect densities: 1.87 × 1012 cm-2 for MoS2 and 1.26 × 1012 cm-2 for WSe2. Our work establishes SPC as a simple and unified mechanistic framework to drive TMD synthesis toward the intrinsic structural limits.

Large-scale carbon nanotube (CNT) synthesis based on floating catalyst chemical vapor deposition (FC-CVD), unlike conventional CVD, utilizes a growth promoter, commonly a sulfur-containing species, whose role in the overall growth process is still poorly understood, hindering more efficient reactor design and a better quality CNT product. By developing a machine-learning interatomic potential here, we conduct atomistic molecular dynamics collision simulations for pure Fe and Fe-S clusters that allow us to directly quantify their sticking probability. Sulfur is found to reduce the intrinsic sticking for small clusters, instead strongly enhancing it for larger sizes. We demonstrate that this crossover is driven by S-induced shape compliance, a mechanism where surface passivation leads to large shape fluctuations that efficiently absorb collision energy. These insights may help rationalize the diverse and sometimes conflicting experimental outcomes reported for S-assisted FC-CVD synthesis of CNTs.

Graphite has remained the dominant anode material in lithium-ion batteries (LIBs), powering portable electronics and electric vehicles (EVs). However, sluggish Li+ diffusion kinetics in natural and synthetic graphite can severely limit charging rates. Overcoming this bottleneck requires the rational design of graphite architectures that enable rapid Li+ transport in LIBs. Here, we disclose a trace-metal-assisted flash (TMF) process for the millisecond synthesis of catalytic flashed graphite (CFGr) with exceptionally fast-charging capabilities. The TMF process induces in situ formation of trace nickel nanoclusters that catalyze ultrafast graphitization of amorphous carbon into highly ordered graphite within <1 s. Raman spectroscopy shows an exceedingly clean graphite material with ID/IG of 0.09, with calculations yielding a binding energy (Eb) of −2.297 eV, while diffraction reveals a sub-angstrom-level interlayer expansion (d002) of 3.4 Å. These afford an enhanced structural stability and Li+ accessibility. Consequently, optimized CFGr achieves a high reversible capacity of 347.4 mAh g−1 at 0.25 C and retains 158.8 mAh g−1 at 15 C with 80% capacity retention after 1000 cycles, outperforming the rate and cyclability of both commercial graphite and graphite prepared by flash Joule heating. The TMF route can replace conventional energy-intensive calcination, reducing energy use and emissions by over 80% and lowering the production cost of premium fast-charging synthetic graphite by ~80% to only US$0.84 kg−1. These findings establish a sustainable, scalable pathway to advance fast-charging graphite anodes into next-generation LIBs.

Morphology control is critical to unlock the full potential of silicon carbide (SiC) as a high-performance reinforcement and semiconducting material. However, conventional synthetic approaches often rely on tailored precursors, catalytic agents, and harsh reaction conditions, limiting scalability and sustainability. Here, we report a fluorine-assisted flash Joule heating process that rapidly upcycles waste glass into morphology-controllable SiC within seconds. Fluorine additives selectively activate iron oxide species in the glass matrix, selectively triggering directional growth of one-dimensional SiC nanostructures. The resulting SiC nanowires exhibit markedly enhanced mechanical reinforcement performance in composites compared to their SiC particle counterparts. The fluorine-assisted flash process can be extended to synthesize one-dimensional carbide nanowires from the class of ultra-high temperature ceramics, such as B4C, TiC, and NbC. This active-element-guided strategy establishes a versatile and scalable platform for controlling nanomaterials morphologies through kinetic modulation, with implications for structural, electronic, and energy-related applications.

The broken mirror symmetry in Janus SMoSe and SWSe monolayers induces novel properties for photocatalytic, thermoelectric and photocatalytic devices. Interlayer coupling is critical in van der Waals (vdW) heterostructure for quantum transport and polaritonics. We investigate Janus SMoSe/SWSe vdW heterostructures with three stacking interfaces: S-S, S-Se, and Se-Se. The S-Se SMoSe/SWSe vdW heterostructure with lowest symmetry exhibits ultralow frequencies of in-plane shear (1.94 cm- 1) and out-of-plane breathing (4.47 cm- 1) modes due to weaker interlayer vdW restoring forces and a significant intrinsic vertical dipole moment. The reduced restoring forces are caused by the critical charge transfer across the vdW interface. Thus, the larger interlayer spacing in the S-Se SMoSe/SWSe heterostructure results in the suppressed vdW interlayer coupling for ultralow phonon frequencies. These findings advance understanding of tuning vdW coupling in polar Janus SMoSe/SWSe heterostructures by stacking engineering, providing theoretical insights for designing tunable nanoelectronic devices.

The modulation of the electronic and magnetic properties of 2D CrI 3 is investigated. The substitutional doping of I with Se impurities can introduce hole carriers and strain, which strongly modulate the physical properties of 2D CrI 3 . The Se impurities are magnetic, with their magnetic direction opposite to that of Cr atoms. Se impurities are very active and contribute shallow impurity bands into the bandgap. As a result, the bandgap of CrI 3 is reduced, and the magnetic exchange interactions between Cr atoms are significantly enhanced. The Curie temperature can be increased up to 250 K, while the large out‐of‐plane magnetic anisotropic energy (MAE) is preserved. The total magnetization, magnetic exchange interactions, and bandgap can be tuned over a wide range by varying the concentration of the Se impurities. Moreover, Se doping enables electronic polarization. The strong magnetoelectric effects of van der Waals (vdW) heterostructures composed of graphene and Janus Cr 2 Se 3 I 3 are also demonstrated.

Kagome metals offer a unique platform for investigating robust electron-correlation effects because of their lattice geometry, flat bands, and multiorbital nature. In the cases with active flat bands, recent theoretical studies have pointed to a rich phase diagram that contains not only electronic orders but also quantum criticality. Very recently, CsCr_{3}Sb_{5} has emerged as a strong candidate for exploring such new physics. Here, using effective tight-binding models obtained from ab initio calculations, we study the effects of electronic correlations and symmetries on the electronic structure of CsCr_{3}Sb_{5}. The effective tight-binding model and Fermi surface comprise multiple Cr-d orbitals and Sb-p orbitals. The introduction of Hubbard-Kanamori interactions leads to orbital-selective band renormalization dominated by the d_{xz} band, concurrently producing emergent flat bands very close to the Fermi level. Our analysis sets the stage for further investigations into the electronic properties of CsCr_{3}Sb_{5}, including electronic orders, quantum criticality, and unconventional superconductivity, which promise to shed much new light into the electronic materials with frustrated lattices and bring about new connections with the correlation physics of a variety of strongly correlated systems.

Two-dimensional transition metal dichalcogenides (2D TMDs) are a promising class of functional materials for fundamental physics explorations and applications in next-generation electronics, catalysis, quantum technologies, and energy-related fields. Theory and simulations have played a pivotal role in recent advancements, from understanding physical properties and discovering new materials to elucidating synthesis processes and designing novel devices. The key has been developments in ab initio theory, deep learning, molecular dynamics, high-throughput computations, and multiscale methods. This review focuses on how theory and simulations have contributed to recent progress in 2D TMDs research, particularly in understanding properties of twisted moiré-based TMDs, predicting exotic quantum phases in TMD monolayers and heterostructures, understanding nucleation and growth processes in TMD synthesis, and comprehending electron transport and characteristics of different contacts in potential devices based on TMD heterostructures. The notable achievements provided by theory and simulations are highlighted, along with the challenges that need to be addressed. Although 2D TMDs have demonstrated potential and prototype devices have been created, we conclude by highlighting research areas that demand the most attention and how theory and simulation might address them and aid in attaining the true potential of 2D TMDs toward commercial device realizations.

A rapid electrothermal method heals spent cathodes. With heteroatom doping, the rejuvenated cathodes show improved performance at 4.6 V. This low-cost, eco-friendly method supports sustainable high-performance lithium-ion battery supply.

Since the first realization of borophene on Ag(111), two-dimensional (2D) boron nanomaterials have attracted substantial interest because of their polymorphic diversity and potential for hosting solid-state quantum phenomena. Here, we use atomic-resolution scanning tunneling microscopy (STM) and field-emission resonance (FER) spectroscopy to elucidate the structure and properties of atomically thin boron phases grown on Cu(111). Specifically, FER spectroscopy reveals charge transfer and electronic states that strongly differ from the decoupled borophene phases observed on silver, suggesting that the deposition of boron on copper results in strong covalent bonding characteristic of a 2D copper boride. This conclusion is reinforced by detailed STM characterization of line defects that are consistent with density functional theory calculations for atomically thin Cu8B14. This evidence for 2D copper boride is likely to motivate future synthetic efforts aimed at expanding the relatively unexplored family of atomically thin metal boride materials.

Programmable self-assembly provides a promising avenue to improve upon traditional synthesis and create multicomponent materials with emergent properties and arbitrary nanoscale complexity. However, its most successful realizations utilizing DNA often use complicated arduous procedures that result in low yields. Here, we employ coarse-grained molecular dynamics to uncover the ranges of temperatures and misbinding strengths needed for successful one-pot self-assembly of generic, two-dimensional (2D), and distinguishable tiles. Analysis of the energies associated with a single-stranded DNA interacting with all other sequences within a mixture revealed that the success of DNA-based assembly is primarily determined by the strongest misbinding a given sequence can encounter with a sequence highly similar to its reverse complement. This enabled us to design optimized sequence ensembles with acceptably weak and consequently rare misbinding. An estimate is provided for the maximum size of, and complexity of sequences needed to synthesize self-assembled structures with high accuracy and yield, with potential relevance for DNA-functionalized low-dimensional materials for electronics and energy storage.

In the quest for topology- and correlation-driven quantum states, kagome lattice materials have garnered significant interest for their band structures, featuring flat bands (FBs) from the quantum destructive interference of the electronic wavefunction. Tuning an FB to the chemical potential could induce electronic instabilities and emergent orders. Despite extensive studies, direct evidence of FBs tuned to the chemical potential and their role in emergent orders in bulk materials remains lacking. Using angle-resolved photoemission spectroscopy, resonant inelastic X-ray scattering, and density functional theory, we show that the low-energy structure of the Cr-based kagome metal superconductor CsCr3Sb5 is dominated by FBs at the Fermi level. We also observe low-energy magnetic excitations evolving across the low-temperature transition, largely consistent with the FB shift. Our results suggest that the low-temperature order contains a magnetic origin and that the kagome FBs may play a role in the emergence of this order.