Carbon Energy最新文献

High-nickel cathode, LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811), and sulfide-solid electrolyte are a promising combination for all-solid-state lithium batteries (ASSLBs). However, this combination faces the issue of interfacial instability between the cathode and electrolyte. Given the surface alkalinity of NCM811, we propose a strategy to construct a solid–polymer–electrolyte (SPE) interphase on NCM811 surface by leveraging the surface alkaline residues to nucleophilically initiate the in-situ ring-opening polymerization of cyclic organic molecules. As a proof-of-concept, this study demonstrates that the ring-opening copolymerization of 1,3-dioxolane and maleic anhydride produces a homogeneous, compact, and conformal SPE layer on NCM811 surface to prevent the cathode from contact and reaction with Li₆PS₅Cl solid-state electrolyte. Consequently, the SPE-modified-NCM811 in ASSLBs exhibits high capacities of 193.5 mA h g^–1 at 0.2 C, 160.9 mA h g^–1 at 2.0 C and 112.3 mA h g^–1 at 10 C, and particularly, excellent long-term cycling stabilities over 11000 cycles with a 71.95% capacity retention at 10 C at 25°C, as well as a remained capacity of 117.9 mA h g^–1 after 8000 cycles at 30 C at 60°C, showing a great application prospect. This study provides a new route for creating electrochemically and structurally stable solid–solid interfaces for ASSLBs.

Silicon-based anode materials have garnered considerable attention in lithium-ion batteries (LIBs) due to their exceptionally high theoretical capacity and energy density. However, intrinsic challenges, such as significant volumetric expansion and the consequent degradation in cycling stability, severely hinder their practical application. As a result, development of silicon anodes that can effectively mitigate volumetric expansions, enhance cycling durability, and improve rate performance has emerged as a critical research focus. However, due to neglect of “size effects”, the modification strategy of silicon-based electrodes lacks systematic, scientific, and comprehensive guidance. Herein, this review starts from the “size effect” of silicon-based materials, and reveals in depth the different failure mechanisms of nano-silicon (Si NPs) and micro-silicon (μSi). Furthermore, this review provides targeted classification of modification strategies for Si NPs and μSi, and reviews comprehensively, in detail, and in depth the latest research progress on silicon-based materials. In addition, the review also comprehensively summarizes the cutting-edge dynamics of matching silicon-based electrodes with solid electrolytes to construct high-energy LIBs. It is hoped that this review can provide comprehensive and systematic scientific guidance for modification strategies of silicon-based electrodes, which is of great significance for promoting the industrialization process of silicon-based electrodes in high-energy LIBs.

Seawater electrolysis is promising for green hydrogen production, while its application is inhibited by sluggish anodic oxygen evolution reaction (OER) and rapid chloride corrosion-induced electrode deactivation. Herein, we report a conductive and ion-selective OER electrocatalyst with a CoFe alloy core and microporous metal-doped carbon shell. Co/Fe-N₄-C active sites in the shell optimize the adsorption strength of intermediates and synergize with the metal core to endow the catalyst with high OER activity and selectivity, while the rich ultra-micropores in the shell demonstrate a significant sieving effect to hinder Cl⁻ transfer, thus protecting the inner Co/Fe-N₄-C active sites and metal core from Cl⁻ corrosion. The catalyst is assembled in an alkaline seawater electrolyzer with an electrode geometric area of 254 cm² and delivers a current density of 3000 A m⁻² at 1.85 V for 330 h. Such catalysts can be synthesized in a large batch (100 g), providing sound opportunities for industrial seawater splitting.

Electrides, in which anionic electrons are trapped in structural cavities, have garnered significant attention for exceptional functionalities based on their low work function. In low-dimensional electrides, a strong quantum confinement of anionic electrons leads to many interesting phenomena, but a severe chemical instability due to their open structures is one of the major disadvantages for practical applications. Here we report that one-dimensional (1D) dititanium sulfide electride exhibits an extraordinary stability originating from the surface self-passivation and consequent durability in bifunctional electrocatalytic activity. Theoretical calculations identify the uniqueness of the 1D [Ti₂S]²⁺·2e⁻ electride, where multiple cavities form two distinct channel structures of anionic electrons. Combined surface structure analysis and in-situ work function measurement indicate that the natural formation of amorphous titanium oxide surface layer in air is responsible for the remarkable inertness in water and pH-varied solutions. This makes the [Ti₂S]²⁺·2e⁻ electride an ideal support for a heterogenous metal-electride hybrid catalyst, demonstrating the enhanced efficiency and superior durability in both the hydrogen evolution and oxygen reduction reactions compared to commercial Pt/C catalysts. This study will stimulate further exploratory research for developing a chemically stable electride in reactive conditions, evoking a strategy for a practical electrocatalyst for industrial energy conversions.

Enhancing the energy density of all-solid-state batteries (ASSBs) with lithium metal anodes is crucial, but lithium dendrite-induced short circuits limit fast-charging capability. This study presents a high-power ASSB employing a novel, robust solid electrolyte (SE) with exceptionally high stability at the lithium metal/SE interface, achieved via site-specific Nb doping in the argyrodite structure. Pentavalent Nb incorporation into Wyckoff 48h sites enhances structural stability, as confirmed by neutron diffraction, X-ray absorption spectroscopy, magic angle spinning nuclear magnetic resonance, and density functional theory calculations. While Nb doping slightly reduces ionic conductivity, it significantly improves interfacial stability, suppressing dendrite formation and enabling a full cell capable of charging in just 6 min (10-C rate, 16 mA cm⁻²). This study highlights, for the first time, that electrochemical stability, rather than ionic conductivity, is key to achieving high-power performance, advancing the commercialization of lithium metal-based ASSBs.

Compared to traditional liquid electrolyte batteries, solid metal batteries offer advantages such as a wide operating temperature range, high energy density, and improved safety, making them a promising energy storage technology. Solid electrolytes, as the core components of solid-state batteries, are key factors in advancing solid-state battery technology. Among various solid electrolytes, Na super ionic conductor (NASICON)-type solid electrolytes exhibit high ionic conductivity (10⁻³ S·cm⁻¹), a wide electrochemical window, and good thermal stability, providing room for the development of high energy-density solid metal batteries. Since the discovery of NASICON-type solid electrolytes in 1976, interest in their use in all-solid-state battery development has grown significantly. In this review, we comprehensively analyze the common features of NASICON lithium-ion conductors and NASICON sodium-ion conductors, review the historical development of NASICON-type solid electrolytes, systematically summarize the transport mechanisms of metal cations in NASICON-type solid electrolytes, discuss the latest strategies for enhancing ionic conductivity, elaborate on the latest methods for improving mechanical stability and interface stability, and point out the requirements of high energy density devices for NASICON-type solid electrolytes as well as three types of in situ characterization techniques for interfaces. Finally, we highlight the challenges and potential solutions for the future development of NASICON-type solid electrolytes and solid-state metal batteries.

Salination of solutions of salinity gradient releases large-scale clean and renewable energy, which can be directly and efficiently transformed into electrical energy using ion-selective nanofluidic channel membranes. However, conventional ion-selective membranes are typically either cation- or anion-selective. A pH-switchable system capable of dual cation and anion transport along with salt gradient energy harvesting properties has not been demonstrated in ion-selective membranes. Here, we constructed an amphoteric heterolayer metal–organic framework (MOF) membrane with subnanochannels modified with carboxylic and amino functional groups. The amphoteric MOF-composite membrane, AAO/aUiO-66-(COOH)₂/UiO-66-NH₂, exhibits pH-tuneable ion conduction and achieves osmotic energy conversion of 7.4 and 5.7 W/m² in acidic and alkaline conditions, respectively, using a 50-fold salt gradient. For different anions but the same cation diffusion transport, the amphoteric membrane produces an outstanding I⁻/CO₃²⁻ selectivity of ~4160 and an osmotic energy conversion of ~133.5 W/m². The amphoteric membrane concept introduces a new pathway to explore the development of ion transport and separation technologies and their application in osmotic energy-conversion devices and flow batteries.

The high chloride (Cl) concentration in seawater presents a critical challenge for hydrogen production via seawater electrolysis by deactivating catalysts through active site passivation, highlighting the need for catalyst innovation. Herein, in situ boron-doped Co₂P/CoP (B-Co_xP) ultrathin nanosheet arrays are prepared as high-performance bifunctional electrocatalysts for seawater decomposition. Density functional theory (DFT) simulations, comprehensive characterizations, and in-situ analyses reveal that boron doping enhances electron density around Co centers, induces lattice distortions, and significantly elevates catalytic activity and durability. Moreover, boron doping reduces *Cl retention time at active sites—defined as the DFT-derived residence time of adsorbed Cl intermediates based on their adsorption energies—effectively mitigating Cl-induced poisoning. In a three-electrode system, B-Co_xP achieves exceptional bifunctional performance with overpotentials of 11 mV for hydrogen evolution reaction and 196 mV for oxygen evolution reaction to deliver 10 and 50 mA·cm^–2, respectively—a result that showcases its superior bifunctional properties surpassing noble metal-based counterparts. In an alkaline electrolyzer, it delivers 1.56 A·cm^–2 at 2.87 V for seawater electrolysis with outstanding stability over 500 h, preserving active site integrity via boron's robust protective role. This study defines a paradigm for designing advanced seawater electrolysis catalysts through a strategic in-situ doping approach.

Front cover image: Lithium-sulfur (Li-S) batteries hold great promise for high-energy-density storage, but their practical performance is hindered by sluggish lithium polysulfide (LiPS) conversion kinetics. To address this issue, in the article numbered e270043, Yang et al. successfully synthesized ultrafine truncated octahedral titanium dioxide nanocrystals (P-O_v-TiO₂) with specific {101} crystal faces, phosphorus doping, and oxygen vacancies under mild conditions. The oxygen vacancies significantly enhance the electron enrichment and charge transfer ability by adjusting the electronic structure; phosphorus doping effectively optimize the d-band center of the catalyst, further strengthening the titanium-sulfur interaction at the {101} crystal faces. This dual-defect engineering enables the exposed {101} crystal faces to exhibit excellent chemical adsorption capacity and catalytic performance. The assembled lithium-sulfur battery using P-O_v-TiO₂ as the separator modification achieves a high specific capacity of 895 mAh g^-1 at 5 C and exhibites a minimal decay rate of 0.14% per cycle over 200 cycles. Additionally, the lithium-sulfur pouch battery delivers a high capacity of 1004 mAh g^-1 under a 0.1 C current density in a low electrolyte condition. This research provides important theoretical basis and new ideas for designing efficient catalysts suitable for lithium-sulfur battery applications.

Back cover image: Layered manganese dioxide (δ-MnO₂) cathodes for aqueous zinc-ion batteries offer high capacity but suffer from sluggish Zn²⁺ diffusion and severe manganese dissolution. In article number e70014, Ding et al. engineer a dual-functional δ-MnO₂ cathode modified with 2-methylimidazole. This synergistic molecular design combines pre-intercalation to expand interlayer spacing (accelerating Zn²⁺ diffusion) and surface coating to form stabilizing Mn–N bonds (suppressing Mn²⁺ dissolution), achieving exceptional capacity and cycling stability.