Carbon capture has emerged as a pivotal decarbonization technology to address global warming driven by excessive CO2 emissions. Porous carbons are promising alternative to promote energy-efficient CO2 capture and separation from post-combustion flue gas. However, their CO2 capture behaviors are greatly restricted by the universal trade-offs between textural properties and surface chemistry. Herein, we develop a synergistic one-step strategy integrating in-situ self-activation and gas blowing to fabricate N, S dual-doped gradient porous carbons. This approach overcomes conventional fabrication limitations, achieving high porosity without compromising heteroatoms doping levels. The gas blowing process not only modulates the morphology from a cross-linked network to nanosheets, but also promotes deep etching of the carbon matrix via self-activation, thereby enhancing porosity while introducing N, S surface functionalization. By adjusting pyrolysis process, the porosity, surface chemistry and morphology can be synergistically optimized. The resultant materials feature a high surface area with a well-balanced hierarchical pore structure spanning ultramicropores to mesopores. The optimal N, S-HPC-650 delivers a promising CO2 capture behavior under simulated flue gas, including a CO2 uptake of 3.25 mmol g-1, exceptional CO2/N2 selectivity of 73 and fast adsorption kinetics at 298 K. Notably, it maintains a satisfactory dynamic CO2 capture capacity and stability even under high humidity (up to 75% RH). By integrating experimental and theoretical analysis, we reveal that for physisorptive carbons, CO2 capture behavior is predominantly governed by porosity, while surface heteroatom groups further enhance performance by introducing supplemental stronger adsorption interactions. This work highlights a facile and effective synergistic route for engineering multifunctional porous carbons, offering new perspectives on the design of higheffective adsorbents for CO2 capture and separation from flue gas.

Despite progress in sodium-ion batteries, developing cathodes with high stability and performance under harsh conditions remains a critical challenge. Herein, a sustainable in-situ Zn substitution method to partially replace Fe in sodium iron hexacyanoferrate (FeHCF) using ZnO as the precursor under acidic media. The resulting Zn-FeHCF-2 exhibits a lower amount of coordinated water (∼10.75%), effectively alleviating lattice strain during repeated Na+ insertion/extraction. As a result, the material delivers highly reversible electrochemical behavior with minimal volume variation according to in-situ XRD. Structural analyses reveal uniform cubic particles with high crystallinity, contributing to mechanical stability and improved charge-transfer kinetics. Electrochemically, the cathode achieves a specific capacity of ∼158.98 mAh g-1 at 0.1 C and maintains excellent rate capability up to 50 C. Moreover, a full cell assembled with Zn-FeHCF-2||hard carbon anode retains 96.5% of its initial capacity (88.34mAh g-1) after 6000 cycles at -20°C. Additionally, density functional theory (DFT) calculations indicate that zinc incorporation lowers the energy barriers for sodium-ion diffusion, thereby facilitating faster reaction kinetics.

Aiming at the bottlenecks of low theoretical specific capacity of commercial graphite anodes that fail to satisfy the escalating demands of industrial energy storage, as well as the drawbacks of insufficient capacity and single-scale pore structures prevalent in existing three-dimensional structures carbon anode candidates, this work adopts density functional theory (DFT) and first-principles computational methods to design a brand-new 3D carbon allotrope designated Pmma-C52. This crystalline framework is constructed by covalently bridging graphene sheets via sp³-hybridized carbon atomic chains, which generates a dual-size pore structure and crystallizes within the Pmma space group. Comprehensive computational verifications demonstrate that Pmma-C52 satisfies all Born–Huang mechanical stability criteria; its phonon spectrum contains no imaginary frequencies, and the framework maintains intact atomic geometry at both 300 K and 1000 K, which confirms good dynamic and thermal stability at the theoretical level. Electronic band calculations reveal semimetallic intrinsic properties of Pmma-C52, alongside graphene-like Dirac cones emerging near the Fermi level, endowing the material with favorable electron transport characteristics. As lithium-ion anodes, Pmma-C52 delivers an ultrahigh theoretical specific capacity of 1331.48 mAh/g, 3.5 times the value of commercial graphite. Meanwhile, the minimum lithium migration barrier reaches merely 0.081 eV, paired with an average open-circuit voltage (OCV) of 0.335 V and a limited volume expansion ratio of 3.4% after full lithiation. In conclusion, Pmma-C52 acts as a porous carbon framework integrating high lithium storage capacity, rapid ion transport kinetics, minor volumetric deformation and robust structural durability, rendering it a promising theoretical candidate for lithium-ion battery anodes.

Electrocatalytic urea synthesis through C-N coupling under ambient conditions represents a promising and sustainable alternative to traditional high-energy industrial processes. However, its efficiency is often limited by the insufficient activity and selectivity of existing electrocatalysts, primarily due to challenges in N2 activation, C-N coupling, and competing side reactions. Here, we theoretically designed a two-dimensional porous boron-carbon network, C9B4, as a metal-free electrocatalyst for efficient urea production. First-principles calculations indicate that C9B4 possesses high stability and excellent electronic properties, characterized by nodal-line semi-metallic behavior. The material features large pores and abundant exposed boron sites, which facilitate efficient N2 adsorption and activation through an electron "donation-backdonation" mechanism. Furthermore, we propose an intramolecular C-N coupling mechanism involving the direct insertion of free CO molecules into the activated N2 or N2Hx species within the two-dimensional porous framework. This mechanism enables urea synthesis on C9B4 via an optimal NHCONH pathway, with a limiting potential as low as -0.618 V and low kinetic barrier for the C-N coupling step. Under constant potential conditions, all elementary steps are exothermic, confirming the high catalytic activity of C9B4. Additionally, C9B4 exhibits high urea selectivity by effectively suppressing competing reactions. This work provides a theoretical foundation for the rational design of efficient metal-free catalysts in sustainable electrochemical urea synthesis.

A central challenge in heterogeneous peroxymonosulfate (PMS) activation is achieving catalysts with highly active interfacial sites to enable both efficient pollutant degradation and environmentally safe water treatment. Herein, cooperative Co/Cu dual-atom sites were anchored on Ti3C2Tx MXene (Co/Cu-Ti3C2Tx). The optimized Co0.5/Cu0.5-Ti3C2Tx catalyst achieved 96.9% removal of the emerging contaminant acetaminophen (APAP) within 60 min via PMS activation, markedly outperforming its single-atom analogues by 21.0-58.6%. Response surface methodology (RSM) analysis indicated that the system operated efficiently under near-neutral pH and mild conditions. Quenching experiments and electron paramagnetic resonance (EPR) analysis suggested that APAP degradation proceeded via a coupled mechanism involving contributions from both reactive oxygen species (predominantly •OH, •O2-, and 1O2) and high-valent metal-oxo species (HVMOS). Density functional theory (DFT) calculations revealed that the synergistic interaction between Co/Cu sites enhanced PMS adsorption, improved electron transfer efficiency, and accelerated the redox cycles between Co0/Co2+ and Cu+/Cu2+, thereby cooperatively promoting the activation of PMS. Based on the identification of intermediates, the degradation pathway of APAP was proposed to involve hydroxylation of the benzene ring, ring-opening, deacetylation, and ultimately oxidative degradation. The biotoxicity of the treated effluent decreased, confirming the effectiveness and environmental safety of the process. These findings advance the mechanistic understanding of bimetallic PMS activation and present a viable approach for the remediation of water containing refractory emerging contaminants.

Carbon-based materials are recognized as promising anode materials for lithium-ion batteries. However, conventional carbon-based systems often fail to achieve fast ion diffusion and high storage capacity due to their reliance on single-direction transport pathways. To overcome this limitation, we theoretically construct a new carbon allotrope, P42/mmc-C12, featuring a unique multidirectional porous architecture with interconnected channels along the x, y, and z axes. This design enables multi-channel Li-ion diffusion, outperforming traditional systems based on one-dimensional channels. Comprehensive first-principles calculations confirm the structural, dynamic, thermal, and mechanical stability of P42/mmc-C12. The material exhibits metallic conductivity, with electronic states near the Fermi level predominantly contributed by the px and py orbitals of C1 atoms, facilitating efficient charge transport. As an anode material for lithium-ion batteries, P42/mmc-C12 delivers a theoretical capacity of 743.8 mA h/g, approximately twice that of graphite, with a favorable open-circuit voltage of 0.77 V. The material exhibits moderate diffusion barriers (0.40–0.58 eV) and remarkably low volume expansion (4.20%) upon lithiation, outperforming graphite in structural stability. This work establishes a new paradigm for designing high-performance carbon-based anodes by leveraging multidirectional pore networks, offering valuable insights into the structure–performance relationship for next-generation energy storage systems.

The development of low-cost and efficient electrocatalysts for the nitrogen reduction reaction (NRR) is essential for sustainable ammonia production under ambient conditions. Dual-atom alloys (DAAs), consisting of transition metal (TM) dimers embedded in the surface of an inert metal host, have recently emerged as promising electrocatalyst candidates. Here, using first-principles calculations, we systematically construct and investigate a series of homonuclear DAAs with TM dimers embedded in the Cu(111) surface (TM2/Cu) as NRR catalysts. Through a multi-step screening strategy and comprehensive evaluation of NRR pathways, W2/Cu, V2/ Cu, and Nb2/Cu are identified as promising catalysts within their respective periods, exhibiting high activity with low limiting potentials of-0.14,-0.34, and-0.40 V, respectively. These DAAs also display excellent stability and high selectivity against the hydrogen evolution reaction. Electronic structure analyses reveal that their superior NRR activity arises from strong N2 adsorption, substantial charge transfer, and effective orbital hybridization between *N2 molecular orbitals and TM d orbitals, which collectively facilitate N2 activation and reduction. Moreover, the N2 adsorption strength and d-band center are identified as reliable activity descriptors for NRR catalyst design. This work not only presents DAAs as cost-effective and high-performance prototypes for ambient NRR, but also provides valuable design principles for next-generation electrocatalysts.

Surface oxygen functionalization enhances CO2 affinity in porous carbons, but the molecular-level roles of distinct oxygen species remain ambiguous. Here, we controllably grafted oxygen groups on ordered mesoporous carbon while preserving its mesostructure by using a mild H2O2 oxidation. Experimental and theoretical analyses reveal that hydroxyl groups work as the dominant sites to enhance low-pressure CO2 uptake, CO2/N2 selectivity, and adsorption kinetics through optimized bidirectional charge transfer and hydrogen-bonding networks. An optimal hydroxyl density maximizes CO2 affinity without inducing steric hindrance or pore collapse. This work provides molecular-level insights and design principles for efficient post-combustion carbonaceous adsorbents.

Recent advancements in sodium-ion batteries (SIBs) have spotlighted their potential as a feasible substitute to lithium-ion batteries, offering advantages in safety, cost-effectiveness, and energy storage capabilities. However, greater size of Na+ poses challenges in comparison with Li+, particularly in ion diffusion rates, energy density, and cycle performance. To counter these drawbacks, we employed a fluidized-phase route to synthesize alpha- and (I-phase Cu2V2O7. Vacancy-rich alpha-Cu2V2O7 (CVO-600) displays far lower charge-transfer resistance than (I-Cu2V2O7 (CVO-550) and sustains 158.7 mAh g-1 at 0.1 A g-1 over 200 cycles, demonstrating that the alpha-phase with oxygen vacancies can mitigate the kinetic penalties imposed by the size of Na+. In-situ XRD shows that both alpha- and (I-phase Cu2V2O7 undergo conversion reactions. This study underscores the critical role of advanced material design in developing next-generation SIBs with enhanced electrochemical characteristics.

The photocatalytic oxygen reduction reaction (ORR) for hydrogen peroxide (H2O2) production via the two-electron pathway offers an environmentally friendly oxidant and a clean fuel. However, the challenge exists in optimal oxygen (O2) adsorption capacities and maintaining O–O bond during O2 activation. Herein, we present a zinc single-atom catalyst (Zn/VN-CN) incorporating nitrogen vacancies (VN), which is designed to modulate the electronic structure of the photocatalyst, leading to optimized O2 adsorption energy and a remarkable enhancement in H2O2 yield. Benefitting from the synergistic effect between nitrogen vacancies and Zn single atoms, the optimized Zn/VN-CN catalyst exhibits a photocatalytic H2O2 production rate of 2.399 mmol g−1 h−1 under visible-light irradiation, representing a 12-fold enhancement compared to pristine g-C3N4 (CN), along with a high H2O2 selectivity of 87.4

Two superhard carbon allotropes, Pnma-C20 and P21/m-C10, have been identified through first-principles calculations. Both phases consist entirely of sp3-hybridized carbon bonds. Their structural stability was confirmed using elastic constants, phonon spectrum analysis, and ab initio molecular dynamics simulations. Pnma-C20 and P21/m-C10 exhibit direct and indirect semiconductor characteristics, with band gaps of 4.19 eV and 3.68 eV, respectively. Their hardness values were calculated to be 82.1 GPa and 82.0 GPa, classifying them as superhard carbon materials. Analysis of their anisotropic mechanical properties revealed anisotropic behavior in Young's modulus, Poisson's ratio, and shear modulus, with anisotropy indicators comparable to those of diamond. Additionally, their anisotropic mechanical properties became more pronounced under increasing pressure. The X-ray diffraction (XRD) peak of Pnma-C20 aligns closely with the unknown XRD peak observed in experimental samples. These findings suggest that Pnma-C20 and P21/m-C10 not only exhibit mechanical properties akin to diamond but also expand the family of carbon-based materials, providing a foundation for future analyses of related unknown structures.

Iridium‐based electrocatalysts are commonly regarded as the sole stable operating acidic oxygen evolution reaction (OER) catalysts in proton‐exchange membrane water electrolysis (PEMWE), but the linear scaling relationship (LSR) of multiple reaction intermediates binding inhibits the enhancement of its activity. Herein, the compressive strain and oxygen vacancy effect exists in iridium dioxide (IrO 2 )‐based catalyst by a doping engineering strategy for efficient acidic OER activity. In situ synchrotron characterizations elucidate that compressive strain can enhance Ir─O covalency and reduce the Ir─Ir bond distance, and oxygen vacancy (O v ) as an electronic regulator causes rapid adsorption of water molecules on the Ir and adjacent Ov (Ir─O v ) pair site to be coupled directly into * O─O * intermediates. Importantly, hence, volcano‐shape curves are established between the compressive strain/oxygen vacancy and OER current using OER as the probe reaction. Theoretical calculation reveals Ni dopant can modulate Ir 5 d ‐ and O 2 p ‐band centers for increasing overlap of Ir 5 d and O 2 p orbits to trigger a continuous metal site‐oxygen vacancy synergistic mechanism (MS‐O V SM) pathway, successfully breaking the LSR of intermediates binding during OER. Therefore, the resultant proton‐exchange membrane water electrolysis (PEMWE) device fabricated using T‐0.24Ni/IrO 2 delivers a current density of 500 mA cm −2 and operates stably for 500 h.

Recent experiments have revealed that the oxygen reduction reaction (ORR) performances of transition-metal and nitrogen codoped carbon (TM-N-C) can be drastically improved by interfacing with TM nanoparticles. However, the key factors that derive from this emerging composite SAC and can well correlate with the boosted ORR activity is still unclear. Herein, taking the FeN4-embedded graphene (FeN4-G) as example, we built a series of model heterointerface systems, by placing FeN4-G on various common TM surfaces (denoted as FeN4-M), to explore the enhancement origin. Based on extensive density functional theory calculations, we find that all the FeN4-M systems exhibit higher ORR activity than the free-standing FeN4-G, and even most FeN4-M systems are much more active than the Pt(111) surface. Furthermore, for the descriptor construction, however there is no apparent correlation between the ORR activity and the electronic structures of Fe active centers, the ones that are closely relevant with ORR activity of the free-standing FeN4-G. Instead, interestingly the interlayer distance between FeN4-G and the underlying metal substrates, an intrinsic geometric structure parameter, has been identified to linearly correlate with the binding strengths of ORR intermediates and ORR overpotential well. Present work provides a novel insight into the structure-activity relationship of the composite SACs consisting of Fe-N-C and metal nanoparticles.

The electrochemical reduction of Nitric Oxide (NO) to ammonia (NH3) has attracted significant attention due to its great promises: the elimination of harmful pollutants and the production of valuable NH3. Nevertheless, the creation of catalysts with high efficiency and selectivity for this procedure poses a substantial obstacle. In this study, utilizing density functional theory (DFT) calculations, we investigate the catalytic potential of various single transition metal atoms supported on VS2 (denoted as TM@VS2) for the electrochemical conversion of NO to NH3. Among the array of catalysts screened, V@VS2 stood out as an exemplary NOER catalyst, notable for its minimal limiting potential of-0.20 V and efficient inhibition of competing reaction channels. Our results offer not just an appropriate electrocatalyst to bolster NOER for ammonia fabrication but also provide a deeper elucidation of the NOER process's operational mechanism, guiding the design of more optimized electrocatalysts.

An Na-excess NASICOM type cathode material, Na3.6Mn1.3Ti0.7(PO3.6F0.4)3 (NMTP@F), was synthesized using a sol-gel method. Electrochemical evaluations revealed that the NMTP@F half-cell exhibits a high discharge capacity of 189.8 mAh g−1 at 0.1 C, excellent high-rate performance with a capacity of 76.7 mAh g−1 at 10 C, and outstanding cycling stability with 90.6% capacity retention after 500 cycles at 1 C. Cyclic voltammetry measurements revealed rapid Na+ transport during the charge–discharge process. Electrochemical impedance spectroscopy further provided quantitative evidence of reduced charge transfer resistance after F doping. Density functional theory calculations revealed that F doping lowers the crystal formation energy of NMTP, enhancing its structural stability. It also reduces the Na extraction energy and narrows the energy bandgap, facilitating rapid Na+ ion transport for high-rate performance. Projected density of states analysis shows F doping induces new spin-up states in Ti and F below the Fermi level, reducing the bandgap from 1.16 to 0.75 eV, improving electronic conductivity.

With the rapid development of electronic devices, the demand for batteries has gradually increased, and existing batteries can no longer satisfy it. In this paper, a three-dimensional honeycomb carbon material is designed and termed pmma-C32. The mechanical stability, dynamic stability, thermal stability, and mechanical stability were investigated through first-principles molecular dynamics, phonon spectrum, and the Born-Huangkun criterion. The calculation results show that pmma-C32 not only has good thermodynamic stability, but also has static stability. Similar to graphene, pmma-C32 exhibits semi-metallic characteristics, featuring two Dirac node lines with high Fermi velocity, indicating a high capacity for electron transport. As a metal-ion battery material, pmma-C32 exhibits higher theoretical capacity(836.8, 732.2, and 418.4 mA h/g for Li, Na, and K), lower diffusion barrier (0.06-0.12 eV for Li, 0.10-0.11 eV for Na, and 0.05-0.06 eV for K), and lower open circuit voltage (0.34 V for Li, 0.37 V for Na, and 0.74 V for K). These remarkable properties endow semimetallic pmmaC32 as a promising anode material for metal-ion batteries, providing fast charge and discharge rates. This research not only broadens the family of three-dimensional carbon materials, but also greatly improves the performance for universal metal-ion battery anode materials through material structure design.

The local electronic structure of the metal active site often dominates the molecular adsorption on single-atom catalysts (SACs), a key process for understanding the catalytic mechanism. Herein, using constant-potential method, we delve into the role of the substrate's electronic structure in molecular adsorption on metal-embedded nitrogen-doped graphene (M-N-C) SACs under electrochemical potential. Using O2 as a model adsorbate and FeN4 and FeNC3 as model SACs, we observe a decrease in O2 adsorption strength with increasing electric potential on FeN4. This behavior is primarily due to changes in the electronic structure of the FeN4 substrate upon O2 adsorption, which causes a downward shift in the Fermi level and, consequently, an upward shift in the potential of zero charge. This shift leads to different responses in the total energy of FeN4 with and without O2 adsorption under applied potential. Further, we find that the O2 adsorption energy difference between FeN4 and FeNC3 follows a quadratic dependence on electric potential, with the parabola's opening controlled by the quantum capacitance difference between FeN4 and FeNC3 with adsorbed O2 . Notably, the electronic states responsible for this difference are distributed across the entire Fe-N-C SACs plane, highlighting again the critical role of the substrate's electronic structure in modulating O2 adsorption. This paper underscores the significant role of the substrate's electronic structure for molecular adsorption on the metal active center of SACs, enhancing the understanding of fundamental molecule-catalyst interactions under electrochemical potential.

Lithium-ion batteries (LIBs) are an efficient energy storage technology that has garnered significant research attention. However, the development of anode materials with high theoretical capacity remains a major challenge. In this study, first-principles calculations were employed to predict a novel three-dimensional (3D) carbonbased anode material featuring a dual-specification pore structure, named Pmma-C44. This material exhibits semi-metallic behavior, low total energy (-9.04 eV/atom), and exceptional structural stability. Owing to its unique pore-channel architecture, Pmma-C44 demonstrates a high theoretical capacity of 963.64 mA h/g and an ultra-low lithium-ion diffusion barrier, with a minimum value of 0.026 eV. Additionally, it undergoes minimal volume change (2.9 %) during cycling and maintains a relatively low average open-circuit voltage of 0.40 V. These findings highlight the outstanding lithium storage performance of Pmma-C44, establishing it as a promising high-performance anode material. Moreover, this study offers novel design principles for next-generation lithium-ion battery anodes.

In single-atom catalysts (SACs), active sites can be positioned in close proximity without forming direct chemical bonds, allowing their catalytic behavior to be modulated through inter-site interactions. However, the atomic-level mechanisms underlying these site proximity effects remain poorly understood. Herein, employing constant-potential density functional theory calculations, we systematically investigate the influence of site proximity on the oxygen reduction reaction (ORR) activity of Fe SACs embedded in pyridinic N-doped graphene (FeN4 SACs). A series of dual-site models (FeN4 DSACs) are constructed, encompassing pristine, axial OH-ligated, and axial O-ligated configurations, along with their corresponding isolated counterparts. Thermodynamic analyses reveal that nearly all FeN4 DSACs exhibit enhanced or comparable stability compared to experimentally reported systems. More importantly, site proximity markedly modulates the ORR activity of Fe centers in DSACs compared to their isolated analogues, and the enhancement up to 103 times is observed for axial OH-ligated FeN4 DSACs. Moreover, the Fe d-band center and charge state exhibit linear correlations with the ORR overpotential, while the Fe spin magnetic moment shows a volcano-like relationship with the overpotential, suggesting these properties as effective descriptors of ORR activity. These findings provide useful insights into the site proximity effect in FeN4 SACs on ORR, and highlight its potential as a design principle for high-performance single-atom electrocatalysts.