Robust two-dimensional magnets are essential for next-generation spintronics. Using first-principles calculations, we demonstrate that only the antiferromagnetic 1H- and 1T-CrSe2 exhibit stable magnon dispersions. The preferred stability of 1T phase originates from spin-ordering polarization of correlated Cr-d states among three low-lying crystal-field levels. These levels are localized with distinct orbital character in the 1T phase, but delocalized in the 1H phase. The full occupation of low-lying levels leads to antiferromagnetic exchange, yielding N & eacute;el temperatures of 310 K (1T) and 274 K (1H). By introducing 25% Se line defects in CrSe2 monolayer, we predict a novel monolayer Cr2Se3 in H and T phases (analogous to their parent 1H/1T-CrSe2). Both Cr2Se3 phases are stable and are half-metallic, with spin (down arrow) band gaps of 1.39 eV (H) and 2.28 eV (T). Cr2Se3/h-BN heterostructures preserve the electronic properties, indicating feasible growth on h-BN substrates. In both phases, the partial occupation of the low-lying crystal-field levels enhances ferromagnetic exchange through hopping between occupied and unoccupied orbitals. Remarkably, Curie temperatures based on the Heisenberg Hamiltonian reach 547 K (H) and 606 K (T). The H phase satisfies the Stoner criterion, while the Heisenberg-like T phase shifts toward the Stoner regime under 2-4% biaxial tensile strain. These results position Cr2Se3 as a promising half-metallic 2D magnet.

The discovery of novel materials through first-principles calculations is an exciting and rapidly advancing frontier in materials science. In this study, we predict three novel layered Sc-based MOenes (Sc2OCl2, Sc2OBr2, and Sc2OI2), employing a variable-composition evolutionary algorithm combined with the first-principles calculations. The predicted bulk materials are thermodynamically and thermally stable. We have also examined the cleavage energy and the electronic and phonon dispersions of the monolayers. Our cleavage energy calculations indicate easy exfoliation of monolayers from their bulk counterparts. Monolayer Sc2OCl2 and Sc2OBr2 demonstrate dynamic stability, while monolayer Sc2OI2 shows instability at the X high symmetry point. Our calculations show that bulk Sc2OX2 are semiconductors with a band gap ranging from 0.51 eV (Sc2OCl2) to 0.59 eV (Sc2OI2). A slight increase in the band gap is observed for the monolayers of Sc2OBr2 and Sc2OI2. Our findings reveal that at a n-type doping concentration of 2x1021 cm-3, bulk Sc2OCl2 has a room temperature electrical conductivity of 4.87 x 105 Sm-1, followed by bulk Sc2OBr2 (3.64 x 105 Sm-1) and bulk Sc2OI2 (4.89 x 105 Sm-1). The bulk Sc2OCl2 halide demonstrate room temperature lattice thermal conductivity of 8.7 Wm-1K-1, significantly surpassing bulk Sc2OBr2 (4.6 Wm-1K-1) and bulk Sc2OI2 (2.8 Wm-1K-1). These results highlight the crucial role of halogen atomic mass in governing thermal transport. We present these moderate to lightweight Sc-based MOenes compounds as promising candidates for further computational and experimental investigations, with the potential to uncover new physics in materials.

Unconventional lattice geometries provide an effective platform for realizing symmetry-protected topological phonon states that can strongly influence lattice heat transport. In this work, we explore the relationship between topological phonon band features and thermal transport in square–octagonal (so) chalcogenide monolayers, namely MoS2 and SnS, by combining first-principles calculations with phonon Boltzmann transport theory. Symmetry analysis reveals the presence of nontrivial phonon band topology in the form of symmetry-protected nodal lines. Crossings between nodal lines carrying different symmetry eigenvalues produce fourfold Dirac points that enhance the phonon group velocity (vg), whereas nearly flat nodal lines lead to strong suppression of vg. The coexistence of these features, together with substantial phonon softening and enhanced anharmonic scattering around the topological band crossings, markedly suppresses the lattice thermal conductivity (κ_l). As a result, room-temperature κ_l values of 4.0 W/mK for so-SnS and 18.7 W/mK for so-MoS2 are obtained, representing reductions by more than a factor of two and eight, respectively, relative to their hexagonal phases. Our results uncover a direct connection between phonon band topology and heat transport in two-dimensional materials, highlighting lattice symmetry and topological band engineering as promising routes for tailoring thermal properties. These findings further suggest opportunities for designing topological phononic and thermoelectric devices with controllable heat flow.

This work investigates proton conduction through a wide range of 2D graphene-like crystals using density functional theory calculations. Our goal focused on understanding the impact of the membrane’s chemical constitution on proton permeability, with particular attention to the effect of sequential substitution using non-metallic elements such as boron, nitrogen, silicon, sulfur, and phosphorus. Results indicate that boron-doped graphene reduces the proton permeation energy barrier, being comparable with values for hexagonal boron nitride. In contrast, nitrogen-doped graphene exhibits a significantly high energy barrier (>4 eV) for proton permeation, suggesting that it is unlikely to support proton conduction at room temperature without having defects on the 2D-monolayer. The use of other elements (O, Si, S, and P) generates a broad spectrum of energy barriers, with distinct trends correlating to changes in pore size driven by the elongation or contraction of the 6-membered rings containing the dopants. In comparison, pure 2D-materials such as phosphorene, silicene, and germanene also arise as promising candidates for proton exchange membrane (PEM) applications due to relatively low proton permeation barriers. However, the increased pore size in these materials may reduce their impermeability to other gases, potentially affecting the performance of the PEM. In addition, we further examined the synergistic effects of multi-element 2D materials, with gallium nitride emerging as a candidate capable of simultaneously enhancing proton permeability and improving membrane mechanical and thermal robustness. This work highlights the importance of exploring additional hetero-doped 2D-materials, where untapped chemical properties may offer further opportunities for optimizing PEM performance.

Two-dimensional transition metal-organic frameworks (TM-MOFs) have emerged as promising catalysts for the electrochemical nitric oxide reduction reaction (NORR) for ammonia production. Using the first-principles calculations and high-throughput computational screening approach, we have investigated the structural stability, NO adsorption behavior, reaction energetics, and selectivity for NORR of TM-Tp MOFs (TM = Sc to Au; Tp = triformylphloroglucinol). Among the screened candidates, Fe-Tp and Ru-Tp emerged as the most efficient catalysts due to their favorable thermodynamic and electrochemical stability, strong NO adsorption, and low energy barrier for the hydrogenation steps. A detailed investigation of the reaction pathways reveals that Fe-Tp and Ru-Tp have low limiting potentials of -0.32 V and -0.35 V, respectively. The selectivity volcano analysis shows that both MOFs preferentially adsorb NO over hydrogen, suppressing the competing hydrogen evolution reaction. Furthermore, ab initio molecular dynamics simulations confirmed their excellent thermal stability. The volcano plot shows that Fe-Tp and Ru-Tp are at the top of the catalytic performance curve, indicating an optimal balance between activity and intermediate binding strength. This work highlights Fe-Tp and Ru-Tp MOFs as highly promising, stable, and selective NORR electrocatalysts for sustainable and efficient electrochemical ammonia synthesis.

Research on the sophisticated relationship between band topology and crystal symmetries in chiral and achiral bulk crystals has led to the discovery of Kramers-Weyl points (KWPs) and Kramers nodal lines (KNLs), which host exotic Fermi surfaces and non-trivial surface states spanning the full Brillouin zone. Extending such topological features to two-dimensional (2D) materials and studying their interplay with lattice disorder are then of great fundamental and practical importance. In this work, we realize the diverse topological properties of pristine and disordered monolayers of transition metal dichalcogenides (TMD). We demonstrate that pristine 1H-TMDs host topological edge states arising from KNLs. The origin of these topological states is the non-trivial Berry curvature at the touching points of the Fermi surface pockets formed by the KNLs. We show using tight-binding analysis that the lattice disorder creates complex asymmetric electron hopping between the nearest neighbors, and can be used to control the monolayer crystal symmetries to realize KNLs and 2D KWPs. The KNLs persist when the lattice disorder is confined to the transition metal layer; however, their number and shape are significantly modified, and their edge states shift to the Fermi level. When disorder is introduced into the chalcogen layers, the symmetries protecting KNLs are broken, and KWPs with 2D dispersion form at the time-reversal invariant momentum (TRIM) points. Furthermore, the lattice disorder increases the number of TRIM points, enhancing the robustness of the KWPs edge states. These 2D KWPs are enclosed by non-trivial Fermi surfaces and carry a finite chiral charge protected by time-reversal symmetry and Kramers degeneracy. Our findings unveil hidden topological properties in TMD monolayers and propose lattice disorder as a route for realizing KNLs and 2D KWPs edge states. The proposed lattice disorder ideas can be extended to other 2D materials, offering new directions for realizing exotic quantum phenomena in monolayer systems.

Sodium-ion batteries are gaining increasing attention, driven by sodium's natural abundance and promising performance for large-scale energy storage. In this work, we evaluate the performance of machine-learning interatomic potentials and Materials Project-trained models in predicting average voltages of electrode materials, demonstrating their potential for screening high energy density cathode materials for sodium-ion batteries. Initially, we tested dual-branch machine learning models for predicting average voltage of electrodes using the Materials Project dataset, spanning tree-based models, deep neural networks, a domain-adapted large language model, and graph neural networks. The results showed that the graph transformer model achieved the highest R2 in the MP dataset. Density Functional Theory calculations were carried out for further validation with sodium layered oxide cathodes. Two machine learning interatomic potential models, namely, universal model for atoms (UMA) and message passing atomic cluster expansion (MACE) were also compared along with the density functional theory results and the graph transformer. The evaluations revealed that the UMA model outperformed the graph transformer and MACE, reaching a mean absolute error of 0.11 V. Motivated by this performance advantage, we evaluated the average voltage and corresponding energy density of 35460 sodium layered oxides using the UMA model.

Sodium-ion (Na-ion) energy storage systems attract growing interest due to sodium's abundance, low cost, and more sustainable extraction compared to lithium (Li). However, the higher ionic radius of Na limits ion mobility and electrode compatibility, leading to a reduced energy density and cycle life. Silica (SiO2) holds promise as an anode material for Na-ion storage due to its high theoretical capacity and natural abundance. Nonetheless, its practical application is limited by poor electrical conductivity and significant volume expansion. To overcome these limitations, we present a facile and cost-effective soft-template method to synthesize hollow SiO2 nanotubebased carbon composites (SiO2/C) as flexible and free-standing electrodes. The hollow nanotube structure offers abundant active sites and promotes rapid Na-ion diffusion, while the carbon matrix enhances electrical conductivity and effectively mitigates volume changes. These combined features enable the SiO2/C composite electrode to deliver excellent electrochemical performance in Na-ion capacitor (NIC). Delivering an energy density (105.12 Wh/kg), power density (3.784 kW/kg), and 93.80 % retention over 8000 cycles, the NIC surpasses many traditional anode materials in overall performance. Density functional theory (DFT) simulations further provide fundamental insights into the mechanism behind charge storage and investigate the interfacial interactions between the Na atom and the composite. Our DFT results confirm enhanced electrical conductivity, faster charge transfer kinetics, and reduced Na-ion diffusion barriers, which is aligned with the experiment. Our findings present a cost-effective strategy for efficient Na-ion energy storage, contributing to the advancement of alternatives to Li-ion technologies.

The global rise in diabetes highlights the urgent need for reliable, low-cost, and sustainable glucose monitoring technologies. In this work, we demonstrate a sustainable and efficient route for fabricating non-enzymatic glucose sensors by directly reusing copper foils recovered from spent Li-ion batteries. This strategy not only repurposes electronic waste but also provides a scalable route for developing eco-friendly electrochemical sensors. Cu(OH)2 nanostructures were grown on recycled Cu foils via a scan-rate-controlled linear sweep voltammetry (LSV) process, allowing precise morphological control and enhanced electrochemical activity. The electrode synthesized at the optimized scan rate exhibited a uniform, porous nanorod morphology, providing a large electroactive surface area and improved ion diffusion pathways. These features enabled superior electrocatalytic activity toward glucose oxidation with excellent selectivity, long-term stability, and high accuracy in real human blood analysis. The repeated regrowth of Cu(OH)2 on the same recycled foil without performance loss highlights the efficient reusability and scalability of this approach. Density functional theory calculations reveal a strong interaction between glucose and the Cu(OH)2 surface, offering an atomic-scale understanding of the bonding mechanism and charge-transfer dynamics compared to other interfering species. These combined experimental and theoretical insights elucidate the glucose oxidation mechanism on Cu(OH)2 and reflect the potential of recycled copper foils for sustainable and cost-effective electrochemical biosensors.

The pursuit of high‐performance anode materials for next‐generation metal‐ion batteries is vital for advancing sustainable energy storage technologies. This review presents a comprehensive overview of carbon‐based anodes, tracing their evolution from conventional materials, like graphite, hard/soft carbon, and graphene to emerging carbon frameworks, including graphyne, graphullerene, biphenylene, and their derivatives. Among these, biphenylene, a recently synthesized 2D carbon allotrope comprising 4‐, 6‐, and 8‐membered rings, has attracted attention for its unique structural, electronic, and mechanical properties, which are well‐suited for alkali metal (Li, Na, K) storage. We compare the synthetic strategies developed for biphenylene with those of other novel carbon allotropes, emphasizing key physicochemical properties, including high surface area, tunable conductivity, intrinsic porosity, structural flexibility, and fast ion transport that make biphenylene and its derivatives promising anode candidates. Recent computational and experimental advances in biphenylene‐based anodes are critically assessed, with a focus on heteroatom doping, functionalization, and morphological engineering, which are essential for optimizing performance. Finally, we discuss the challenges, knowledge gaps, and future research directions toward the rational design of next‐generation biphenylene‐based anodes as promising materials for metal‐ion batteries.

Thermoelectric (TE) technology can play a promising role in the energy landscape but its low efficiency remains a significant drawback in pratical applications. . This review gives information regarding the strategies for boosting thermoelectric performance, such as band engineering, nanostructuring, defect engineering, and Anderson Localization. Band engineering can enhance the power factor by increasing band effective mass (md∗)while maintaining high carrier mobility (μ) and increasing the conducting bands Nv. Nanostructuring techniques profoundly impact thermoelectric performance by tailoring the material's microstructure, leading to enhanced carrier scattering, reduced thermal conductivity, and improved electrical transport, thereby opening up promising avenues for high-efficiency thermoelectric applications. Defect engineering, encompassing the introduction of vacancies, nanoprecipitates, and dislocations as efficient phonon scattering centers, emerges as a compelling strategy for optimizing thermoelectric properties through enhanced phonon scattering and charge carrier transport, presenting promising prospects for advancing high-performance thermoelectric materials. Recent theoretical and experimental studies have demonstrated that thermoelectric (TE) improvement is possible through an enhanced Seebeck coefficient, achieved via Anderson localization, which is characterized by a nonzero, small electrical conductivity when the chemical potential lies below the localization threshold within a single mobility edge. This effect becomes prominent when the chemical potential lies below the localization threshold within a single mobility edge. In conclusion, the integration of nanostructuring, band engineering, defect engineering, and Anderson localization offers remarkable potential to enhance the thermoelectric properties of materials. These synergistic approaches hold great promise in unlocking the full potential of thermoelectric technology and advancing sustainable energy solutions for the future.

The electrochemical nitrogen reduction reactions (NRR) offer a sustainable alternative to the energy‐intensive Haber–Bosch process ammonia synthesis at ambient conditions. In this study, we employ the first‐principles density functional theory (DFT) calculations to systematically investigate 3 d transition metal‐decorated holey graphyne (TM@hGY, TM = Sc‐Zn) as single‐atom electrocatalysts for NRR. Sc, Ti, V, Cr, and Fe exhibit robust thermodynamic and thermal stability on the hGY substrate among the screened candidate materials. Mechanistic analysis of the NRR pathway reveals that Cr@hGY and Fe@hGY achieve favorable limiting potentials of −0.34 and −0.49 V, respectively, suggesting high catalytic activity. However, Fe@hGY suffers from poor selectivity due to dominant hydrogen evolution reaction activity. Consequently, only Cr@hGY demonstrates high NRR activity, making it the most promising and selective catalyst among the investigated TM@hGY systems for efficient electrochemical ammonia synthesis under ambient conditions. This work provides valuable theoretical insight into the rational design of low‐cost, high‐performance single‐atom catalysts based on 2D carbon frameworks for sustainable ammonia production.

This study addresses the challenge of selective CO2-to-CO conversion via the reverse water-gas shift (RWGS) reaction using atomically dispersed dual-atom catalysts (DACs). Three PdIr/TiO2 compositions with varying Pd-to-Ir ratios (10:90, 25:75, and 40:60) were synthesized and characterized. Among them, PdIr/TiO2 (10 % Pd, 90 % Ir) demonstrated the highest CO2 conversion (74.77 %) and 99 % CO selectivity. In contrast, higher Pd loadings (>25 %) led to a decline in both activity and selectivity. Advanced characterization, including in-situ gas-phase transmission electron microscopy (TEM) and Electron energy loss spectroscopy (EELS), revealed atom mobility and nanocluster formation under reaction conditions, along with enhanced Ti-O hybridization, oxygen vacancies, and partial Ti-4(+) reduction due to hydrogen spillover from PdIr sites. Complementarily, density functional theory (DFT) and in situ diffuse reflectance infrared spectroscopy (DRIFTs) studies revealed a hydrogen-assisted reaction pathway involving *COOH intermediates that dissociate to form CO. These insights highlight the role of dual-metal synergy and support interactions in stabilizing active sites and guiding selective reaction pathways. Overall, this work demonstrates the potential of DACs to overcome current limitations in CO2 hydrogenation and contributes to the development of more sustainable catalytic processes for greenhouse gas mitigation.

This study presents a significant advancement in electrochemical energy storage by designing and synthesizing MoS2/ZnFe2O4 Nanocomposites (NCs) with exceptional electrochemical properties. The NCs were synthesized using a hydrothermal process, combining MoS2 Nanosheets (NS) with ZnFe2O4 Nanoparticles (NPs). This design leverages the synergistic benefits of both materials, resulting in superior capacitive performance compared to previous reports. The optimized 1:1 molar ratio of MoS2/ZnFe2O4 NC demonstrated a specific capacitance of 2076.9 F/g at 25 A/g and retained 94.3 % of its capacitance after 2500 cycles. The MoS2 NS acts as a substrate to prevent ZnFe2O4 NP agglomeration, while the ZnFe2O4 NPs inhibit MoS2 NS restacking. Density functional theory (DFT) calculations reveal that the MoS2/ZnFe2O4 interface introduces new energy states near the Fermi level, boosting the heterostructure's capacitance. With their enhanced electrochemical performance, these NCs show great potential for diverse advanced energy storage and conversion systems.

We study the experimentally synthesized layered material CsMnBi using first-principles calculations and the linearized electron and phonon Boltzmann transport equations. CsMnBi is found to be a semiconductor with an indirect bandgap of 0.76 eV and to realize C-type antiferromagnetism, which is energetically favorable by 0.19 eV per formula unit over ferromagnetism. Energetical overlap between the acoustic and low-frequency optical phonon modes enhances the phonon-phonon scattering. Combined with low group velocities and high lattice anharmonicity this results in an ultralow lattice thermal conductivity of 0.07 W m-1 K-1 at 300 K. A high thermoelectric figure of merit of 2.2 (1.7) is achieved at 300 K at a hole (electron) density of 6.0 × 1018 (1.0 × 1018) cm-3.

Electrochemical nitrogen reduction reaction offers a sustainable alternative to the energy-intensive Haber-Bosch for Ammonia (NH3) synthesis. The electrocatalytic performance of heteronuclear double transition metal catalysts (TM2@C2N, TM = Fe, Co, Ni, Cu, and Mo) anchored on C2N monolayer is investigated using the firstprinciples calculations. The binding energy calculations confirm that all structures are thermodynamically stable except for the Ni-Cu@C2N catalyst. A selectivity test between NRR and the competing hydrogen evolution reaction (HER) identifies five catalysts that exhibit NRR selectivity. The Co-Mo@C2N and Ni-Mo@C2N catalysts stand out, achieving 100 % Faradaic efficiency, making them highly promising candidates for efficient NH3 production. Our calculated reaction pathways identify potential-determining steps for alternating and distal mechanisms. Co-Mo@C2N demonstrates a limiting potential of -0.57 eV compared to -0.77 eV in the case of Ni-Mo@C2N. The synergistic role of Co and Mo atoms in Co-Mo@C2N, particularly during the distal mechanism, highlights the advantage of heteronuclear active sites in enabling efficient electrocatalytic N2 conversion to NH3. Our ab-initio molecular dynamics simulations confirm the thermal stability of selected catalysts under operating conditions. Our findings highlight the crucial role of heteronuclear sites in improving catalytic efficiency and selectivity. The robust structural stability, efficient charge transfer, and favorable reaction energetics position these Co-Mo@C2N and Ni-Mo@C2N catalysts in the list of highly promising catalysts for sustainable ammonia production through the electrochemical NRR.

The increasing demand for lithium-ion batteries (LIBs) is driving rapid advancements in energy storage technologies, with the market anticipated to expand significantly in the near future. With the growing role of electric vehicles (EVs), global e-waste generation is expected to rise significantly, creating challenges for waste management and resource conservation. This work presents a novel approach to recycle spent LIB copper foil into a high-performance Cu(OH)2/graphene oxide (GO) composite anode for lithium-ion capacitors (LICs). Using a straightforward single-step electro-etching method, we create a flexible, binder-free Cu(OH)2/GO composite electrode that exhibits exceptional electrochemical performance in both LIB and LIC applications. The Cu(OH)2/ GO composite electrode delivers a high initial discharge capacity of 2068 mAh/g in the half-cell LIB configuration. In the full cell LIC device, the electrode demonstrates superior charge storage capacity, high energy density (141.75 Wh/kg), high power density (6.47 kW/kg), and remarkable cyclic stability (93 % retention over 10,000 cycles). The research also highlights the repeated recycling of copper foil to maintain performance consistency, emphasizing the potential for sustainable electrode manufacturing. Theoretical and experimental studies, including density functional theory analysis, confirm the electrode's enhanced properties, highlighting a major advancement in recycling and energy storage technology. The current work establishes a strong foundation for sustainable e-waste recycling in energy storage systems.

Graphene and graphene oxide (GO) are promising materials in fuel cell applications due to their selective proton transport and exceptional mechanical and thermal stability properties. In this study, we explored the different mechanisms of electrochemically driven proton permeation through graphene and graphene oxide by using ReaxFF molecular dynamics simulations. Our findings reveal that the primary mechanism for proton transport in graphene and graphene oxide is the flipping mechanism, in which the proton first adsorbs onto the surface and flips through the basal graphene ring. However, direct permeation of protons through the center of the graphene ring is also observed. Additionally, our results show that the proton conductivity increases with temperature due to the high thermal energy and a less negative surface charge density. In the case of graphene, as the temperature increases from 300 to 350 K, the proton conductivity rises from 0.014 to 0.020 mS/cm, showing a 43% improvement. In the case of graphene oxide, the proton conductivity at 300 K is two folds that of graphene. Furthermore, the proton conductivity of graphene oxide improves from 0.031 to a maximum of 0.038 mS/cm, showing a 23% improvement as the hydroxyl group concentration increases (0.75OH:0.25OE). Our results highlight the crucial role of functional groups; a higher concentration of the hydroxyl groups enhances the proton conductivity, while epoxy groups influence the surface geometry and charge density distribution of graphene oxide. Our study offers valuable insights into tunable proton conductivity in graphene-based materials.

Molybdenum disulfide (MoS2) holds significant potential as a semiconductor for next-generation flexible thermoelectric modules, but its high thermal conductivity and low figure of merit have limited its commercial viability. In this study, we report a breakthrough, achieving a record-high n-type (p-type) thermoelectric figure of merit of 1.42 (1.25) at 1000 K, coupled with a thermoelectric conversion efficiency of 16 % (14 %) (along armchair direction), outperforming commercially available thermoelectric modules. Our first-principles calculations on rippled monolayer MoS2 show a transition from a direct to indirect band gap semiconductor at a rippling amplitude (r) of 1.0 & Aring; and metal at r >= 3.0 & Aring;. The maximum n-type Seebeck coefficient of 0.66 mV/K (0.59 mV/K) achieved along the armchair direction, at r = 0.5 & Aring; (1.5 & Aring;), at 1000 K is notable in the case of flexible thermoelectric materials. A high electrical conductivity contributes to an optimal power factor of 0.68 mW/mK2 along the armchair direction. The phonon dispersion reveals the dynamic stability of the system up to r = 1.5 & Aring;. The forbidden gap between the acoustic and optical phonons branches reduces as r increases. An ultralow room temperature lattice thermal conductivity x l of 1.44 W/mK along the armchair direction is obtained at r = 1.5 & Aring;, which further reduces to 0.44 W/mK at 1000 K. The obtained value is 100-fold smaller than the room temperature x l of pristine monolayer MoS2 (144.60 W/ mK). Our findings reveal a noteworthy n-type figure of merit (ZT) of 0.45 at 300 K (r = 1.50 & Aring;) along the armchair direction, which is one order of magnitude more than the pristine monolayer MoS2. A significant thermoelectric conversion efficiency of 13 %, taking a temperature gradient of 700 K, is obtained, outperforming Bi2Te3-based thermoelectric materials. These results highlight the potential of lattice distortions, which can be induced using bulged substrates, to drastically reduce the lattice thermal conductivity of MoS2 and other 2D materials, opening new possibilities for strain-engineered flexible electronic devices.

Two-dimensional (2D) materials emerge as promising alternatives to conventional polymer-based proton exchange membranes (PEMs) due to their high proton conductivity, mechanical robustness, and surface tunability. Here we present an integrated framework combining ab initio molecular dynamics (AIMD) simulations and machine learning (ML) to accelerate the discovery of proton- and hydrogen-transport properties over 866 nonmetallic 2D materials. Three ML models were trained using AIMD-derived permeation barriers from 488 materials, with Random Forest achieving the highest accuracy and revealing structure-property relationships that govern proton transport. Critical descriptors, including proton-atom distance, pore size, interlayer spacing, and electron affinity, emerged as key predictors of permeation behavior. H+/H2 selectivity through additional AIMD simulations allowed identifying 18 promising candidates, including the experimentally studied graphene and hexagonal boron nitride, thus supporting the robustness of our approach. Experimentally synthesized but barely explored materials, including 2D Si, Ge, TeC, TeCl, GeSe and CSe, emerged as strong candidates for proton conducting membranes. The framework further highlights theoretically stable compounds as unexplored opportunities for PEMs. By integrating atomic-scale simulations with data-driven models, this work provides both fundamental insights into proton permeation mechanisms and practical guidance for designing selective, high-performance nanomaterials for hydrogen energy technologies.