Ethanol dehydrogenation to acetaldehyde represents an efficient pathway for ethanol valorization, capitalizing on the versatile utility of acetaldehyde as a key chemical intermediate and the inherently high atom economy of the dehydrogenation process. Copper (Cu)-based catalysts have demonstrated good catalytic activity in this reaction. However, their practical application is hampered by insufficient long-term stability, and the nature of the active sites under operational conditions remains ambiguous. Herein, we report a rationally designed Cu-Beta zeolite catalyst where isolated Cu atoms are anchored within silanol nests of a dealuminated beta (deAl-Beta) zeolite framework, forming well-defined {(equivalent to SiO)2Cu(HO-Si equivalent to)2} coordination sites. These isolated Cu species undergo spontaneous self-evolution during the reaction or H2 reduction conditions, transforming into confined Cu nanoparticles (2-3 nm) within the zeolite mesopores. The Cu nanoparticles are stabilized through zeolite confinement and interfacial Cu-O-Si interactions, exhibiting substantial catalytic performance with 85% conversion, 95% acetaldehyde selectivity, and stability exceeding 200 h (weight-time yield of similar to 1570 mg gcat -1 h-1). Combining in situ XAS, in situ IR, and DFT calculations, we revealed a stepwise reaction mechanism involving sequential O-H and C alpha-H bonds of ethanol, followed by H-H coupling, all facilitated by the confined Cu nanoparticles. This study highlights a strategy of in situ active site self-optimization through reaction-induced nanostructural confinement, establishing an effective paradigm for designing highly stable and efficient heterogeneous catalysts via dynamic structural evolution.

Lithium‑sulfur batteries (LSBs) suffer from lithium polysulfide (LiPS) shuttling and slow redox kinetics. To mitigate these issues, we report an efficient electrocatalytic interlayer based on a FeCoNiCrMn high-entropy alloy embedded in N-doped carbon nanofibers (HEA@NCNF). The multi-metallic HEA offers abundant active sites, while the N-doped carbon shell not only prevents HEA particle agglomeration and metal leaching, but also establishes a three-dimensional conductive network. Combined X-ray photoelectron spectroscopy and density functional theory calculations elucidate the underlying mechanism: electron modulation from the N-doped carbon layer raises the d-band center of the HEA, thereby strengthening LiPS adsorption and promoting its electrocatalytic conversion. Consequently, the HEA@NCNF interlayer functions as an efficient "trap-and-convert" reactor for LiPSs, which simultaneously suppresses shuttle effects and accelerates redox kinetics. The cells with HEA@NCNF demonstrate exceptional cycling and rate performance, with a capacity decay of only 0.023% per cycle over 1500 cycles at 1C. Remarkably, this superior performance extends to challenging conditions, including high sulfur loading (≥ 7 mg cm-2), lean electrolyte, and high-rate operation. This work demonstrates a strategy of integrating HEAs with conductive N-doped carbon matrices to create a synergistic trap-convert mediator for LiPSs.

Cation engineering has significantly advanced high-entropy oxides for electrocatalysis, but anion doping has received comparatively limited attention. This study demonstrates that fluorine doping in quinary perovskite oxide La(Cr-0.Mn-2(0).Fe-2(0).Co-2(0).Ni-2(0).(2))O-3 (F-LM5) substantially enhances the oxygen evolution reaction (OER) performance. F-LM5 exhibits a low overpotential of 0.33 V at 10 mA cm(-2) and a Tafel slope of 47.4 mV dec(-1), demonstrating superior activity and stability compared to the pristine LM5 and single-metal analogues. Spectroscopic and theoretical analyses reveal that the high electronegativity of fluorine optimizes the transition-metal electronic structure by stabilizing active high-valence states, increasing oxygen vacancies, while selectively suppressing catalytically unfavorable Cr6+. The pH-dependent measurements and theoretical calculations suggest that fluorine incorporation promotes energetically favorable conditions for the lattice oxygen-mediated mechanism, evidenced by a reduction in potential-determining step free-energy barriers at Co and Ni sites. This work demonstrates anion engineering as an effective strategy for enhancing the catalytic efficiency of multicomponent oxides.

Room-temperature sodium-sulfur (Na & horbar;S) batteries are appealing candidates for large-scale energy storage owing to their high theoretical capacity and the use of earth-abundant, low-cost active materials. The quasi-solid conversion in Na & horbar;S batteries was proposed as a promising mechanism, lying between solid-liquid-solid and solid-solid mechanisms, with suppressed polysulfide dissolution while retaining faster kinetics, enabling stable, high-performance Na & horbar;S batteries. To realize the quasi-solid conversions, the rational design of the cathode-electrolyte interphase is the key; however, the study is at an early stage. Herein, a multifunctional cross-linked polymer (MCP) is first introduced as an artificial interface for the quasi-solid sulfur conversions in Na-S batteries with enhanced stability, faster kinetics, mechanical robustness, and improved chemical confinement. The MCP interfaces demonstrate significantly improved electrochemical performances for various nanocarbon hosts with a one-step quasi-solid sulfur reversible conversion mechanism, even under high sulfur loading. Our study offers new insights and design guidelines for artificial interfaces enabling quasi-solid conversion in Na & horbar;S batteries.

Nonradiative recombination originating from the defect-rich SnO2/perovskite buried contact and the absorber interior imposes a major constraint on photovoltaic output and device durability. Here, ethylenediaminetetraacetic acid dipotassium salt (EDTA-2K) is inserted as a molecular bridge that modifies the chemical environment and electronic structure on both sides of this buried junction. Its multiple binding sites coordinate with undercoordinated Sn4+ on SnO2 and Pb2+ in the perovskite. In parallel, K+ supplied by EDTA-2K combines with iodide to form KI, while the remaining functional groups interact with halides through hydrogen bonding; together, these effects impede halide migration. This concerted regulation lowers the defect density, relaxes interfacial strain, guides perovskite growth, and produces a more favorable depth distribution of residual PbI2. It also improves interfacial energy alignment and electron extraction. Employing poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) for hole transport enabled the best-performing cell to achieve a power conversion efficiency (PCE) of 24.32%. Following 3000 h of storage, the remaining efficiency exceeds 95% of the starting value; a separate 500 h test under intense ultraviolet (UV) light in ambient air leaves 94.77% of the original PCE. The proposed interfacial architecture thus combines high photovoltaic performance with pronounced resistance to UV-induced aging.

ABSTRACT Room‐temperature sodium–sulfur (RT Na–S) batteries offer high energy density and low cost but suffer from poor conductivity, sluggish redox kinetics, and polysulfide shuttling. This study introduces a multifunctional Cu 2 O@MXene separator with a hierarchical porous structure and a 3D MXene network for fast electron transport. The hierarchical porous structure provides physical confinement, while the polar Cu─O bonds and Cu + Lewis acid centers in Cu 2 O provide chemical anchoring and catalytic sites for sodium polysulfides (NaPSs). Experimental evidence and theoretical calculations reveal that MXene serves as an electronic reservoir to protect Cu + catalytic active sites from reduction, enabling NaPSs anchoring through interfacial Cu─S and Ti─S bonds. Benefiting from this synergistic adsorption‐catalytic mechanism, the Cu 2 O@MXene interlayer enhances NaPSs confinement and accelerates sulfur redox kinetics. Consequently, Cu 2 O@MXene‐PP cells achieve 942.1 mAh g −1 after 100 cycles at 0.2 C and ultralong cycling stability of 574.9 mAh g −1 after 3500 cycles at 2 C. Under a sulfur loading of 4.65 mg cm −2 , the cell retains 3.1 mAh cm −2 after 105 cycles. Theoretical calculations further reveal that Cu 2 O@MXene enables stronger NaPSs adsorption and improves the thermodynamical favorability of the Na 2 S 2 to Na 2 S conversion. This work provides reasonable guidelines for designing Cu‐based catalytic separators in high‐performance RT Na‐S batteries.

Grain refinement is widely recognized as an effective strategy for simultaneously improving the strength and plasticity of Mg alloys. In this study, a novel GNP@MgO nanoparticles with a unique composite structure were synthesized by utilizing the in-situ reaction between CO2 and Mg. The results showed that the confinement effect of MgO particles on the GNP surface enables GNP@MgO to achieve uniform dispersion in the Mg matrix. Simultaneously, the GNP@MgO nanoparticles also significantly refined the grain structure and improved the mechanical properties of the AZ91 alloy. The average grain size of the AZ91 alloy was reduced markedly from 535 to 77 μm, corresponding to a grain refinement efficiency of 86%. The significant grain refinement was mainly attributed to the synergistic regulatory effect of graphene and magnesium oxide, specifically: the Al4C3 phase formed through the in-situ conversion of graphene promoted the heterogeneous nucleation of α-Mg grains; MgO nanoparticles located near grain boundaries effectively restricted grain growth. Furthermore, HRTEM analysis of Al4C3/Mg interface confirmed a specific crystallographic orientation relationship between Al4C3 and α-Mg, described as 13 (003)Al4C3//(002)Mg, and [1-210]Al4C3//[11-20]Mg. Additionally, the formation and growth process of the Al4C3 phase in the Mg-Al-C system is discussed in detail, and the interfacial diffusion model demonstrates that rod-like Al4C3 morphology results from the markedly increased lateral growth relative to the longitudinal growth of the Al4C3 phase. This work provides new design ideas and theoretical guidance for the microstructure control and performance improvement of cast magnesium alloys.

The instability of the solid electrolyte interphase (SEI) remains a primary barrier to the commercialization of lithium metal batteries. Herein, a novel inorganic-rich high-entropy SEI (predominantly consisting of Li halides) is designed and constructed through the in situ electrochemical conversion of a Ti3C2Cl2/Ti3C2Br2/Ti3C2I2@carbon fiber (HCF) skeleton. Theoretical studies and experimental results reveal that the halogen terminals of MXene in the HCF skeleton are electrochemically stripped, forming corresponding lithium halide components in the SEI. This in situ-generated high-entropy SEI demonstrates low surface roughness, a low surface potential, rapid Li+ transport, and excellent mechanical properties. Detailed kinetic analyses indicate that the high-entropy SEI facilitates the desolvation and transport processes of Li*, significantly enhancing the kinetics of Li deposition. Benefiting from the high-entropy SEI, the Li-HCF anode delivers an excellent rate performance up to 20 mA cm-2 and sustains stable cycling for over 4300 h at 1 mA cm-2 in symmetric cells. With a high-loading LiNi0.8Co0.1Mn0.1O2 cathode (20 mg cm-2), the full cell demonstrates exceptional cycling stability, retaining 85.6% of its capacity over 200 cycles at 0.5 C. This high-entropy interface strategy offers a straightforward and effective route to establish a stable interphase on Li metal anodes.

IrRu nanoparticles surrounded by Ir/Ru–N–C exhibit high CO tolerance arising from CO removal via the following reaction: CO ad –IrRu nanoparticle + OH ad –Ir/Ru–N–C → COOH ad .

Wastewater contaminated with copper ions (Cu2+) poses irreversible harm to the ecological environment and human health. Capacitive deionization (CDI), an environmentally friendly water purification technology characterized by high adsorption capacity and low energy consumption, has attracted much attention. The purification capacity of CDI devices is directly determined by their electrode materials. In this work, a heterogeneous composite material (Ni/NiSe2/CNT), which was composed of encapsulated nickel particles, nickel selenide anchored on the carbon framework, and bamboo-like carbon nanotubes, was prepared through an ion exchange-vapor deposition synergistic preparation strategy with ZIF-8 as the precursor. The design and construction of Ni/ NiSe2/CNT effectively inhibits the agglomeration and volume expansion effects of NiSe2 particles, and exposes abundant electrochemical active sites. Importantly, the hybrid capacitive deionization (HCDI) device assembled with Ni/NiSe2/CNT as the cathode exhibits excellent purification performance towards Cu2+. Under the synergistic mechanism of electrical double-layer capacitance and Cu2+ electrodeposition, the HCDI device achieves a remarkably high electrochemical adsorption capacity of 77.3 mg g-1 for 50 mg L-1 Cu2+ at an applied voltage of 1.0 V. This work not only provides new insights for designing HCDI electrode materials with high purification capability but also offers a new strategy for the deep purification of heavy metal ion-contaminated water bodies.

Most existing studies on high-entropy alloy (HEA) sulfur electrocatalysts rely on changing elemental species to adjust their affinity for lithium polysulfides (LiPSs) and matching redox catalytic activity, so as to alleviate the intrinsic trade-off between LiPS adsorption and desorption. In this work, interconnected carbon fibers (CF) modified with CrMnFeCoNi HEA nanoparticles of tunable atomic ratios are synthesized to uncover the correlation between catalytic activity and surface electronic configuration toward efficient sulfur electrocatalysis. Combining density functional theory (DFT) calculations and systematic experimental characterizations, we demonstrate that tuning the atomic ratios of metallic elements within CrMnFeCoNi HEA can redistribute their surface charge, shift the positions of the d-band center, and ultimately regulate their adsorption affinity toward LiPSs. The optimized HEA catalyst achieves a favorable balance between adsorption and desorption, which drastically boosts the catalytic efficiency of LiPS conversion. Consequently, the cell based on the optimized CF/HEA-1 interlayer delivers a high reversible capacity of 938 mAh g⁻1 and maintains stable long-term cycling over 2000 cycles at 1.0 C, corresponding to an ultralow capacity decay rate of 0.022% per cycle. This work proposes a feasible electronic modulation strategy to optimize HEA catalytic behavior, providing valuable guidance for the design of advanced lithium-sulfur battery electrocatalysts.

Aiming at the critical challenges of competitive hydrogen evolution reaction (HER) and sluggish reaction kinetics in CO2 electroreduction reaction (CO2RR), a uniquely structured nitrogen-doped porous carbon-embedded Ni single-atom catalyst (Ni-N3O2/NPC) was designed and synthesized by virtue of density functional theory (DFT) calculations and mild thermal treatment strategies. The as-synthesized catalyst was verified by aberration-corrected scanning transmission electron microscopy (AC-STEM) and X-ray absorption spectroscopy (XAS) to possess an asymmetric configuration featuring Ni-N3O1 motif with axial oxygen ligand, which agrees well with the DFT modeling. CO2RR results validated that the Ni-N3O2/NPC-400 catalyst exhibited 99% Faraday efficiency for CO (FECO) across a wide potential window of-0.3 to-1.0 V vs. reversible hydrogen electrode (RHE) in flow cell, reaching a maximum FECO of 99.9% at-1.0 V vs. RHE with an turnover frequency (TOF) of 63,579 h-1, showcasing potential for industrial CO2 emission reduction. In situ attenuated total reflection infrared spectroscopy (ATR-IR) further confirmed the formation of key *COOH and *CO intermediates during the CO2RR process. Theoretical calculation unveiled that the axial oxygen ligand in Ni-N3O2 configuration synergistically promoted CO2RR kinetics by inducing electronic polarization. The present work not only provides a theoretical basis for axial ligand engineering to regulate the electronic state of single-atom catalysts, but also opens up a new direction for designing high-efficiency CO2RR catalysts.

Transition metal-nitrogen-carbon (M-N-C) catalysts show great promise for converting CO2 into valuable fuels and chemicals via electroreduction (CO2RR). Nonetheless, controversy remains regarding which specific MNx coordination structure in M-N-C catalysts governs CO2RR performance. We synthesized a series of Ni-NOMC catalysts with high specific surface area and varying NiN3-Pyr site loadings using SBA-15 as a template, employing a small molecule condensation and pyrolysis strategy. Aberration-corrected scanning transmission electron microscopy (AC-STEM) and X-ray absorption spectroscopy (XAS) confirmed the presence of atomically dispersed Ni sites coordinated by pyrrolic nitrogen (NiN3-Pyr). The Ni-NOMC-3 catalyst, with a higher NiN3-Pyr loading, achieved a remarkable CO Faraday efficiency (FECO) of 99.6% at -0.57 V vs. the reversible hydrogen electrode (RHE), while maintaining FECO > 99% across a broad potential window (-0.17 to -0.97 V vs. RHE). Moreover, the ordered mesoporous structure of this catalyst enhances mass transport properties and optimizes active site accessibility, enabling a high CO partial current density of 157 mA & centerdot;cm(-)& sup2; in a flow cell system. Theoretical simulations further reveal that the NiN3-Pyr coordination structure exhibits superior catalytic performance for CO2RR-to-CO compared to other possible NiNx configurations.

High-entropy oxides have garnered significant attention as a promising catalyst for lithium-sulfur batteries. However, their development has been hindered by intractable structures and unclear catalytic mechanisms. We conducted simultaneous structural engineering of high-entropy metal oxides nanoparticles embedded in 2D porous carbon sheets (HEO-C) across atomic, nano, and micro scales. In the prepared HEO nanoparticles, we observed and confirmed the presence of numerous ion vacancies, likely resulting from lattice distortions. The presence of these ionic vacancies can furnish supplementary edge adsorption and catalytic sites for lithium polysulfide conversion, and augment catalytic activity through modulation of the d-band center. Furthermore, the high entropy of HEO-C attributes in inducing the rapid dissociation and conversion of long-chain lithium polysulfides, improving redox kinetics. As a result, cells equipped with the HEO-C catalyst exhibited outstanding electrochemical rate performance, delivering 761 mAh g(-1) at 3 C, along with excellent cycling stability-retaining 80.44% capacity after 1000 cycles at 1 C. The high surface area of HEO-C facilitates the reduction of inactive components in the cell while preserving the catalytic activity, enhancing the potential for practical application. The assembled pouch cell with the HEO-C catalyst achieved a reversible capacity of 968 mAh g(-1) and retained 81.33% of its capacity after 200 cycles at 0.1 C.

ABSTRACT Rapid industrial development has led to wastewater discharge containing refractory toxic organics, posing a severe threat to aquatic ecosystems and water security. As a typical recalcitrant pollutant, p ‐nitrophenol (PNP) is hard to degrade due to its stable benzene ring and electron‐withdrawing nitro group, demanding efficient removal methods. This study synthesized a MIL‐53(Fe)/CuCo 2 S 4 composite (MCCS‐15, ‐20, ‐25, and ‐30) via hydrothermal method and constructed a heterogeneous photo‐Fenton system (composite/visible light/H 2 O 2 ) for PNP degradation. Among samples, MCCS‐25 exhibited the highest degradation performance, achieving a rate constant of 0.08613 min −1 , which is 9.06 and 23.03 times greater than that of MIL‐53(Fe) and CuCo 2 S 4 , respectively. Photoelectrochemical measurements revealed that the loading of CuCo 2 S 4 not only broadened the visible light absorption range of MIL‐53(Fe), but also significantly improved the separation efficiency of photogenerated electron‐hole pairs. Scavenger experiments and EPR analyses confirmed that hydroxyl radical (OH) and superoxide radical (O 2 − ) were the predominant reactive species in the degradation process. The possible degradation mechanism was proposed based on the band structures of MIL‐53(Fe) and CuCo 2 S 4 . The MIL‐53(Fe)/CuCo 2 S 4 /visible light/H 2 O 2 system demonstrates promising application potential for efficient degradation of PNP.

Coupling hierarchical microstructure with interfacial electronic regulation provides a practical route to improve photocatalytic hydrogen peroxide (H2O2) production through the two-electron oxygen reduction reaction (2e− ORR). Here, flower-like In2S3/ZnIn2S4 (IS/ZIS) S-scheme heterojunctions were fabricated by a two-step hydrothermal method. Under visible-light irradiation (λ ≥ 420nm), the optimized 10% IS/ZIS sample achieved H2O2 production rates of 5.08mmolg-1h-1 in an ethanol-containing aqueous medium and 4.26mmolg-1h-1 in pure water, corresponding to 3.8- and 4.7-fold increases relative to pristine ZIS and IS, respectively. The catalyst retained 95.5% of its initial activity after ten cycles. IS incorporation increased the BET surface area to 78.19 m2g-1 while preserving the nanosheet-assembled flower-like architecture and creating intimate IS/ZIS heterointerfaces. Photocurrent, EIS, PL, and TRPL measurements consistently indicated improved carrier separation and transport. RRDE measurements yielded an electron-transfer number of approximately 2.34 and H2O2 selectivity of 83.12%, supporting preferential 2e− ORR. DFT calculations showed that the IS/ZIS interface strengthened O2 adsorption to −0.836eV and lowered the largest uphill free-energy change of the proposed peroxide-forming pathway to 0.50eV. These results establish a quantitative link between hierarchical accessibility, interfacial charge regulation, O2 activation, and H2O2 production in an all-sulfide heterojunction.

Ultrafast interfacial charge transfer in functionalized two-dimensional semiconductors enables precise modulation of their optical and electronic properties. Herein, we report the axial integration of a triply fused porphyrin dimer (TFP) onto few-layer MXene (Ti3C2Tx) nanosheets via a stepwise covalent strategy comprising initial pyridine anchoring followed by metal-coordination-driven TFP assembly. Z-scan measurements conducted under nanosecond (532 nm) and femtosecond (800 nm) laser excitation both reveal significantly enhanced nonlinear optical absorption relative to the pristine constituents. This enhancement is mainly attributed to the photoinduced charge transfer from the TFP donor to the Ti3C2Tx acceptor matrix, as corroborated by steady-state and transient absorption spectroscopy in conjunction with theoretical calculations. Beyond the demonstration of a high-performance optical limiter, this work establishes a molecular-level design paradigm for engineering interfacial electronic coupling in hybrid two-dimensional architectures subjected to intense optical fields.