Potassium escaping balances the degree of graphitization and pore channel structure in hard carbon to boost plateau sodium storage capacity.

Biomass holds significant potential for large-scale synthesis of hard carbon (HC), and HC is seen as the most promising anode material for sodium-ion batteries (SIBs). However, designing a HC anode with a rich pore structure, moderate graphitization and synthesis through a simple process using a cost-effective precursor to advance SIBs has long been a formidable challenge. This is primarily because high temperatures necessary for pore regulation invariably lead to excessive graphitization.

A Universal Interfacial Reconstruction Strategy Based on Converting Residual Alkali for Sodium Layered Oxide Cathodes: Marvelous Air Stability, Reversible Anion Redox, and Practical Full Cell.

Mn-based layered oxide cathodes have attracted widespread attention due to high capacity and low cost, however, poor air stability, irreversible phase transitions, and slow kinetics inhibit their practical application. Here, we propose a universal interfacial reconstruction strategy based on converting residual alkali to tunnel phase NaMnO for addressing the above mentioned issue simultaneously, using O3 NaNiFeMnO@2 mol % NaMnO (NaNFM@NMO) as the prototype material. The optimized material exhibits an initial capacity and energy density comparable with lithium-ion batteries.

Mitigating Mechanical Stress by the Hierarchical Crystalline Domain for High-Energy P2/O3 Biphasic Cathode Materials.

Sodium-ion batteries (SIBs) have captured widespread attention for grid-scale energy storage owing to the wide distribution and low cost of sodium resources. Delivery of high energy density with stable retention remains a challenge in developing cathode candidates for rechargeable SIBs. Inspired by the concept of "cationic potential", here, we present a hierarchical crystalline domain in hexagonal particles with target chemical composition (NaLiMgNiFeMnTiO) from the inner bulk O3 phase (71.

Revealing the structural influence mechanism of intrinsic potassium/calcium elements on bio-waste-derived hard carbon for sodium-ion batteries.

Waste gourd shells enriched with ash-forming elements are selected as raw materials in this paper, discovering that the K and Ca compounds in the precursor not only exhibit the ability of self-forming pores, but also demonstrate catalytic graphitization of the hard carbon during the pyrolysis procedure.

An MXene-supported NHCNT and BiOCl composite as a sulfur reservoir for Li-S batteries with high energy density.

To solve the intractable challenges of Li-S batteries, we synthesized MXene-NHCNT-BiOCl- to be used as a sulfur host. The M-N-B-10%-S electrode exhibited superior electrochemical performance. XRD measurement confirmed that the M-N-B-10%-S electrode displayed good cycle stability.

Bimetallic Coupling Strategy Modulating Electronic Construction to Accelerate Sulfur Redox Reaction Kinetics for High-Energy Flexible Li-S Batteries.

Lithium-sulfur (Li-S) batteries are considered the most promising energy storage battery due to their low cost and high theoretical energy density. However, the low utilization rate of sulfur and slow redox kinetics have seriously limited the development of Li-S batteries. Herein, the electronic state modulation of metal selenides induced by the bi-metallic coupling strategy is reported to enhance the redox reaction kinetics and sulfur utilization, thereby improving the electrochemical performance of Li-S batteries.

Reviving Sodium Tunnel Oxide Cathodes Based on Structural Modulation and Sodium Compensation Strategy Toward Practical Sodium-Ion Cylindrical Battery.

As a typical tunnel oxide, NaMnO features excellent electrochemical performance and outstanding structural stability, making it a promising cathode for sodium-ion batteries (SIBs). However, it suffers from undesirable challenges such as surface residual alkali, multiple voltage plateaus, and low initial charge specific capacity. Herein, an internal and external synergistic modulation strategy is adopted by replacing part of the Mn with Ti to optimize the bulk phase and construct a Ti-containing epitaxial stabilization layer, resulting in reduced surface residual alkali, excellent Na transport kinetics and improved water/air stability.

Strategies to boost the electrochemical performance of bismuth anodes for potassium-ion batteries.

Potassium-ion batteries (PIBs) are considered potential candidates for large-scale energy storage systems due to the abundant resources of potassium. Among various reported anode materials, bismuth anodes with the advantages of high theoretical specific capacity, low cost, and nontoxicity have attracted widespread attention. However, bismuth anodes experience significant volume changes during the charge/discharge process, leading to unsatisfactory cycling stability and rate performance.

Phosphorous and Nitrogen Dual-Doped Carbon as a Highly Efficient Electrocatalyst for Sodium-Oxygen Batteries.

Sodium-oxygen batteries have been regarded as promising energy storage devices due to their low overpotential and high energy density. Its applications, however, still face formidable challenges due to the lack of understanding about the influence of electrocatalysts on the discharge products. Here, a phosphorous and nitrogen dual-doped carbon (PNDC) based cathode is synthesized to increase the electrocatalytic activity and to stabilize the NaO superoxide nanoparticle discharge products, leading to enhanced cycling stability when compared to the nitrogen-doped carbon (NDC).

Structural Engineering of Prussian Blue Analogues Enabling All-Climate and Ultralong Cycling Sodium-Ion Batteries.

The development of cost-efficient, long-lifespan, and all-climate sodium-ion batteries is of great importance for advancing large-scale energy storage but is plagued by the lack of suitable cathode materials. Here, we report low-cost Na-rich Mn-based Prussian blue analogues with superior rate capability and ultralong cycling stability over 10,000 cycles via structural optimization with electrochemically inert Ni atoms. Their thermal stability, all-climate properties, and potential in full cells are investigated in detail.

Entropy-Assisted Anion-Reinforced Solvation Structure for Fast-Charging Sodium-Ion Full Batteries.

Anion-reinforced solvation structure favors the formation of inorganic-rich robust electrode-electrolyte interface, which endows fast ion transport and high strength modulus to enable improved electrochemical performance. However, such a unique solvation structure inevitably injures the ionic conductivity of electrolytes and limits the fast-charging performance. Herein, a trade-off in tuning anion-reinforced solvation structure and high ionic conductivity is realized by the entropy-assisted hybrid ester-ether electrolyte.

Enabling Efficient Anchoring-Conversion Interface by Fabricating Double-Layer Functionalized Separator for Suppressing Shuttle Effect.

Lithium-sulfur batteries (LiSBs) with high energy density still face challenges on sluggish conversion kinetics, severe shuttle effects of lithium polysulfides (LiPSs), and low blocking feature of ordinary separators to LiPSs. To tackle these, a novel double-layer strategy to functionalize separators is proposed, which consists of Co with atomically dispersed CoN decorated on Ketjen black (Co/CoN@KB) layer and an ultrathin 2D TiCT MXene layer. The theoretical calculations and experimental results jointly demonstrate metallic Co sites provide efficient adsorption and catalytic capability for long-chain LiPSs, while CoN active sites facilitate the absorption of short-chain LiPSs and promote the conversion to LiS.

Cross-linked KMnO nanoflower composites for high rate and low overpotential Li-CO batteries.

Rechargeable Li-CO batteries are deemed to be attractive energy storage systems, as they can effectively inhale and fix carbon dioxide and possess an extremely high energy density. Unfortunately, the irreversible decomposition of the insoluble and insulating LiCO results in awful electrochemical performance and inferior energy efficiency of Li-CO batteries. Furthermore, the low energy efficiency will exacerbate the extra waste of resources.

Carbon Superstructure-Supported Half-Metallic VO Nanospheres for High-Efficiency Photorechargeable Zinc Ion Batteries.

Photorechargeable zinc ion batteries (PZIBs), which can directly harvest and store solar energy, are promising technologies for the development of a renewable energy society. However, the incompatibility requirement between narrow band gap and wide coverage has raised severe challenges for high-efficiency dual-functional photocathodes. Herein, half-metallic vanadium (III) oxide (VO) was first reported as a dual-functional photocathode for PZIBs.

Hollow Core-Shelled NaFeNi(PO)PO with Tiny-Void Space Capable Fast-Charge and Low-Temperature Sodium Storage.

Iron-based mixed polyanion phosphate NaFe(PO)PO (NFPP) is recognized as a promising cathode for Sodium-ion Batteries (SIBs) due to its low cost and environmental friendliness. However, its inherent low conductivity and sluggish Na diffusion limit fast charge and low-temperature sodium storage. This study pioneers a scalable synthesis of hollow core-shelled NaFeNi(PO)PO with tiny-void space (THoCS-0.

Emerging high voltage V/V redox reactions in NaV(PO)-based cathodes for sodium-ion batteries.

NaV(PO) (NVP) cathode materials with the advantages of long cycle life and superior thermal stability have been considered promising cathode candidates for SIBs. However, the unsatisfactory energy density derived from low theoretical capacity and operating voltage (3.35 V Na/Na, based on the V/V redox couple) inevitably limits their practical application.

P-doped spherical hard carbon with high initial coulombic efficiency and enhanced capacity for sodium ion batteries.

Hard carbon (HC) is one of the most promising anode materials for sodium-ion batteries (SIBs) due to its cost-effectiveness and low-voltage plateau capacity. Heteroatom doping is considered as an effective strategy to improve the sodium storage capacity of HC. However, most of the previous heteroatom doping strategies are performed at a relatively low temperature, which could not be utilized to raise the low-voltage plateau capacity.

Insights into dynamic structural evolution and its sodium storage mechanisms of P2/P3 composite cathode materials for sodium-ion batteries.

Cobalt substitution for manganese sites in NaMnO initiates a dynamic structural evolution process, yielding a composite cathode material comprising intergrown P2 and P3 phases. The novel P2/P3 composite cathode exhibits a reversible phase transition process during Na extraction/insertion, showcasing its attractive battery performance in sodium-ion batteries.

Industrial-Scale Hard Carbon Designed to Regulate Electrochemical Polarization for Fast Sodium Storage.

Given the merits of abundant resource, low cost and high electrochemical activity, hard carbons have been regarded as one of the most commercializable anode material for sodium-ion batteries (SIBs). However, poor rate capability is one of the main obstacles that severely hinder its further development. In addition, the relationships between preparation method, material structure and electrochemical performance have not been clearly elaborated.

Hard carbon for sodium-ion batteries: progress, strategies and future perspective.

Because of its abundant resources, low cost and high reversible specific capacity, hard carbon (HC) is considered as the most likely commercial anode material for sodium-ion batteries (SIBs). Therefore, reasonable design and effective strategies to regulate the structure of HCs play a crucial role in promoting the development of SIBs. Herein, the progress in the preparation approaches for HC anode materials is systematically overviewed, with a special focus on the comparison between traditional fabrication methods and advanced strategies emerged in recent years in terms of their influence on performance, including preparation efficiency, initial coulombic efficiency (ICE), specific capacity and rate capability.

Anion-Reinforced Solvation Structure Enables Stable Operation of Ether-Based Electrolyte in High-Voltage Potassium Metal Batteries.

Electrolytes with anion-dominated solvation are promising candidates to achieve dendrite-free and high-voltage potassium metal batteries. However, it's challenging to form anion-reinforced solvates at low salt concentrations. Herein, we construct an anion-reinforced solvation structure at a moderate concentration of 1.

Regulation of the d-band center of metal-organic frameworks for energy-saving hydrogen generation coupled with selective glycerol oxidation.

The hybrid electrolyzer coupled glycerol oxidation (GOR) with hydrogen evolution reaction (HER) is fascinating to simultaneously generate H and high value-added chemicals with low energy input, yet facing a challenge. Herein, Cu-based metal-organic frameworks (Cu-MOFs) are reported as model catalysts for both HER and GOR through doping of atomically dispersed precious and nonprecious metals. Remarkably, the HER activity of Ru-doped Cu-MOF outperformed a Pt/C catalyst, with its Faradaic efficiency for formate formation at 90% at a low potential of 1.