Self-Relaxant Superelastic Matrix Derived from C60 Incorporated Sn Nanoparticles for Ultra-High-Performance Li-Ion Batteries

Bio-Inspired Electrodes with Rational Spatiotemporal Management for Lithium-Ion Batteries

Lithium-ion batteries (LIBs) are currently the predominant energy storage power source. However, the urgent issues of enhancing electrochemical performance, prolonging lifetime, preventing thermal runaway-caused fires, and intelligent application are obstacles to their applications. Herein, bio-inspired electrodes owning spatiotemporal management of self-healing, fast ion transport, fire-extinguishing, thermoresponsive switching, recycling, and flexibility are overviewed comprehensively, showing great promising potentials in practical application due to the significantly enhanced durability and thermal safety of LIBs. Taking advantage of the self-healing core-shell structures, binders, capsules, or liquid metal alloys, these electrodes can maintain the mechanical integrity during the lithiation-delithiation cycling. After the incorporation of fire-extinguishing binders, current collectors, or capsules, flame retardants can be released spatiotemporally during thermal runaway to ensure safety. Thermoresponsive switching electrodes are also constructed though adding thermally responsive components, which can rapidly switch LIB off under abnormal conditions and resume their functions quickly when normal operating conditions return. Finally, the challenges of bio-inspired electrode designs are presented to optimize the spatiotemporal management of LIBs. It is anticipated that the proposed electrodes with spatiotemporal management will not only promote industrial application, but also strengthen the fundamental research of bionics in energy storage.

Enhancing Li-Ion Battery Anodes: Synthesis, Characterization, and Electrochemical Performance of Crystalline C60 Nanorods with Controlled Morphology and Phase Transition

Recently, C60 has emerged as a promising anode material for Li-ion batteries, attracting significant interest due to its excellent lithium storage capacity. The electrochemical performance of C60 as an anode is largely dependent on its internal crystal structure, which is significantly influenced by the synthesis method and corresponding conditions. However, there have been few reports on how the synthesis process affects the crystal structure and Li+ storage capacity of C60. This study used the liquid-liquid interface precipitation method and a low-temperature annealing process to fabricate one-dimensional C60 nanorods (NRs). We thoroughly investigated synthesis conditions, including the growth time, drying temperature, annealing time, and annealing atmosphere. The results demonstrate that these synthesis conditions directly impact the morphology, phase transition, and electrochemical efficiency of pure C60 NRs. Remarkably, the hexagonal close-packed structural C60 NRs-6012h, in a metastable form, exhibits a reversible Li+ storage capacity as an anode material in Li-ion batteries. Furthermore, the face-centered cubic C60 NRs-603001h electrode shows significantly enhanced rate performance and long-cycle stability. A discharge-specific capacity of 603 mAh g-1 was maintained after 2000 cycles at a current density of 2 A g-1. This study elucidates the effect of synthesis conditions on C60 crystals, offering an effective strategy for preparing high-performance C60 anode materials.

Plasma Technology for Advanced Electrochemical Energy Storage

"Carbon Peak and Carbon Neutrality" is an important strategic goal for the sustainable development of human society. Typically, a key means to achieve these goals is through electrochemical energy storage technologies and materials. In this context, the rational synthesis and modification of battery materials through new technologies play critical roles. Plasma technology, based on the principles of free radical chemistry, is considered a promising alternative for the construction of advanced battery materials due to its inherent advantages such as superior versatility, high reactivity, excellent conformal properties, low consumption and environmental friendliness. In this perspective paper, we discuss the working principle of plasma and its applied research on battery materials based on plasma conversion, deposition, etching, doping, etc. Furthermore, the new application directions of multiphase plasma associated with solid, liquid and gas sources are proposed and their application examples for batteries (e. g. lithium-ion batteries, lithium-sulfur batteries, zinc-air batteries) are given. Finally, the current challenges and future development trends of plasma technology are briefly summarized to provide guidance for the next generation of energy technologies.

Hydrothermal synthesis and electrochemical properties of Sn-based peanut shell biochar electrode materials

Using activated-carbon-based electrodes derived from waste biomass in super-capacitor energy technologies is an essential future strategy to achieve sustainable energy and environmental protection. Biomass feed-stocks such as bamboo and straw have been used to prepare activated carbon-based electrodes. This experiment used peanut shells (waste biomass) as carbon precursors. Peanut shell-activated biochar materials were prepared using KOH activation and heat treatment, and SnO2@KBC-CNTs, a composite electrode material of biochar loaded with tin oxide. It was produced through hydrothermal synthesis, utilizing SnCl4-5H2O as the tin precursor. The application of KOH activators during pyrolysis markedly enhanced the porosity and specific surface area of the resultant activated biochar, due to effective dispersion and degradation of pyrolytic products. Characterized by a micro-mesoporous structure, the composite's pores boasted a specific surface area of 158.69 m2 g-1. When tested at a density of current of 0.5 A g-1, the specific capacitance of SnO2@KBC-CNTs reached 198.62 F g-1, nearly doubling the performance of the KBC electrode material alone. Moreover, the composite demonstrated a low ion transfer resistance of 0.71 Ω during charge-discharge cycles.

Catalytic fabrication of graphene, carbon spheres, and carbon nanotubes from plastic waste

In this study, we reported sustainable and economical upcycling methods for utilizing plastics such as polyethylene terephthalate (PET) and polypropylene (PP) compiled from the garbage of a residential area as cheap precursors for the production of high-value carbon materials such as graphene (G), carbon spheres (CS), and carbon nanotubes (CNTs) using different thermal treatment techniques. Graphene, carbon spheres, and carbon nanotubes were successfully synthesized from PET, PP, and PET, respectively via catalytic pyrolysis. XRD and FTIR analyses were conducted on the three materials, confirming the formation of carbon and their graphitic structure. TEM images displayed uniform and consistent morphological structures of the fabricated materials. EDX data confirmed that the prepared carbon-based materials only contained carbon and oxygen without any significant contaminations. XPS results revealed significant peaks in the C 1s spectra associated with sp2 and sp3 hybridized carbon for the three materials. BET spectra showed that the prepared CNTs (54.872 m2 g-1) have the highest surface area followed by carbon spheres (54.807 m2 g-1). The thermal stability of graphene surpassed both carbon spheres and carbon nanotubes which is mainly attributed to the stronger inter-molecular bonds of graphene. Based on the characterization of the prepared materials, these materials are promising to be utilized in environmental remediation applications due to their high carbon content, low cost, and high surface area.

Chitosan modulated engineer tin dioxide nanoparticles well dispersed by reduced graphene oxide for high and stable lithium-ion storage

Tin based materials are widely investigated as a potential anode material for lithium-ion batteries. Effectively dispersing SnO₂ nanocrystals in carbonaceous supporting skeleton using simplified methods is both promising and challenging. In this work, water soluble chitosan (CS) chains are employed to modulate the redox coprecipitation reaction between stannous chloride (SnCl₂) and few-layered graphene oxide (GO), where the excessive restacking of the corresponding reduced graphene oxide sheets (RGO) has been effectively inhibited and the grain size of the in-situ formed SnO₂ nanoparticles have been significantly controlled. In particular, the CS molecules are gradually detached from the RGO sheets with the GO deoxygenation process, leaving only a small quantity of CS remnants in the intermediate SnO₂@CS@RGO sample. The final SnO₂/CSC/RGO sample with significantly improved microstructure is synthesized after a simple thermal treatment, which delivers a high specific capacity of 842.9 mAh g^-1 at 1000 mA·g^-1 for 1000 cycles in half cells and a specific capacity of 410.5 mAh g^-1 at 200 mA·g^-1 for 100 cycles in full cells. The reasons for the good lithium-ion storage performances for the SnO₂/CSC/RGO composite have been studied.

Rationally integrated nickel sulfides for lithium storage: S/N co-doped carbon encapsulated NiS/Cu2S with greatly enhanced kinetic property and structural stability

Nickel sulfides are promising anode materials for lithium-ion batteries (LIBs) due to their high theoretical capacities but suffer from the sluggish kinetic process and poor structural stability. Herein, we develop...

Optimizing SnO2- x /Fe2 O3 Hetero-Nanocrystals Toward Rapid and Highly Reversible Lithium Storage

Engineering oxygen vacancy and boosting Li₂ O reversibility on oxides-based electrode are of significance but remains a challenge in high-power lithium-ion batteries. Herein, the heterogenous SnO_{2- x} /Fe₂ O_{3- y} nanocrystals are demonstrated with tailorable x and y values enabled by a glucose-assisted spray combustion technique. Density functional theory calculations unveil the SnO_{2- x} /Fe₂ O₃ with a maximum x value has the optimal electronic structure, the metallic Fe generated from Fe₂ O₃ can markedly reduce the free energy to break Li-O bonds for accelerating subsequent delithiation process of Li₂ O. Consequently, the optimized SnO_{2- x} /Fe₂ O₃ exhibits a remarkably enhanced electrochemical reversibility and reaction kinetics. After stabilized by reduced graphene oxide, the hybrid delivers a high reversible specific capacity of 1113 mAh g^-1 with superior rate performance (474 mAh g^-1 at 20 A g^-1 ) and long cycle life (negligible loss after 500 cycles at 5 A g^-1 ), the oxygen vacancy and microstructure are well-maintained after cycles. This work provides the possibilities for skillfully regulating oxygen vacancy and meantime enhancing Li₂ O reversibility.

Abnormally High-Lithium Storage in Pure Crystalline C60 Nanoparticles

Li⁺ intercalates into a pure face-centered-cubic (fcc) C₆₀ structure instead of being adsorbed on a single C₆₀ molecule. This hinders the excess storage of Li ions in Li-ion batteries, thereby limiting their applications. However, the associated electrochemical processes and mechanisms have not been investigated owing to the low electrochemical reactivity and poor crystallinity of the C₆₀ powder. Herein, a facile method for synthesizing pure fcc C₆₀ nanoparticles with uniform morphology and superior electrochemical performance in both half- and full-cells is demonstrated using a 1 m LiPF₆ solution in ethylene carbonate/diethyl carbonate (1:1 vol%) with 10% fluoroethylene carbonate. The specific capacity of the C₆₀ nanoparticles during the second discharge reaches ≈750 mAh g^-1 at 0.1 A g^-1 , approximately twice that of graphite. Moreover, by applying in situ X-ray diffraction, high-resolution transmission electron microscopy, and first-principles calculations, an abnormally high Li storage in a crystalline C₆₀ structure is proposed based on the vacant sites among the C₆₀ molecules, Li clusters at different sites, and structural changes during the discharge/charge process. The fcc of C₆₀ transforms tetragonal via orthorhombic Li_x C₆₀ and back to the cubic phase during discharge. The presented results will facilitate the development of novel fullerene-based anode materials for Li-ion batteries.

A Supramolecular Complex of C60 -S with High-Density Active Sites as a Cathode for Lithium-Sulfur Batteries

The well-known "shuttle effect" of the intermediate lithium polysulfides (LiPSs) and low sulfur utilization hinder the practical application of lithium-sulfur (Li-S) batteries. Herein, we describe a novel C₆₀ -S supramolecular complex with high-density active sites for LiPS adsorption that was formed by a simple one-step process as a cathode material for Li-S batteries. Benefiting from the cocrystal structure, 100 % of the C₆₀ molecules in the complex can offer active sites to adsorb LiPSs and catalyze their conversion. Furthermore, the lithiated C₆₀ cores promote internal ion transport inside the composite cathode. At a low electrolyte/sulfur ratio of 5 μL mg^-1 , the C₆₀ -S cathode with a sulfur loading of 4 mg cm^-2 exhibited a high capacity of 809 mAh g^-1 (3.2 mAh cm^-2 ). The development of the C₆₀ -S supramolecular complex will inspire the invention of a new family of S/fullerenes as cathodes for high-performance Li-S batteries and extend the application of fullerenes.

Architectural Engineering Achieves High-Performance Alloying Anodes for Lithium and Sodium Ion Batteries

Tremendous efforts have been dedicated to the development of high-performance electrochemical energy storage devices. The development of lithium- and sodium-ion batteries (LIBs and SIBs) with high energy densities is urgently needed to meet the growing demands for portable electronic devices, electric vehicles, and large-scale smart grids. Anode materials with high theoretical capacities that are based on alloying storage mechanisms are at the forefront of research geared towards high-energy-density LIBs or SIBs. However, they often suffer from severe pulverization and rapid capacity decay due to their huge volume change upon cycling. So far, a wide variety of advanced materials and electrode structures are developed to improve the long-term cyclability of alloying-type materials. This review provides fundamentals of anti-pulverization and cutting-edge concepts that aim to achieve high-performance alloying anodes for LIBs/SIBs from the viewpoint of architectural engineering. The recent progress on the effective strategies of nanostructuring, incorporation of carbon, intermetallics design, and binder engineering is systematically summarized. After that, the relationship between architectural design and electrochemical performance as well as the related charge-storage mechanisms is discussed. Finally, challenges and perspectives of alloying-type anode materials for further development in LIB/SIB applications are proposed.

Porous Cu Film Enables Thick Slurry-Cast Anodes with Enhanced Charge Transfer Efficiency for High-Performance Li-Ion Batteries

The ever-growing demand for energy in the consumer market has put higher requirements on the energy density of Li-ion batteries. Many researchers have strived to discover new electrode materials with higher capacity, while little attention has been focused on improving the cell structure. How to increase the thickness of conventional slurry-cast electrodes as well as decrease the charge transfer resistance by improving the electrode structure is an urgent problem for enhancing the energy density of Li-ion batteries. Here, a porous Cu film is developed to replace the conventional Cu foil current collector, and a thick graphite anode (300 μm) is engineered by two-side slurry casting. The anode delivers a maximum capacity of 18 mAh cm^-2 or 301.3 mAh g^-1 under a highly active mass loading of 60 mg cm^-2, much higher than that fabricated on Cu foil. The assembled full cell with the graphite anode and the LiFePO₄ cathode achieves high energy densities of 36.2 mWh cm^-2 and 283.3 Wh kg^-1. Systematic experimental and simulation investigations reveal the enhanced performance benefits from the facilitated charge transfer efficiency by the porous Cu current collector. This work provides a new strategy for engineering thick electrodes for high-energy Li-ion batteries by improving the conventional electrode structure.

Rational Construction of 2D Fe3 O4 @Carbon Core-Shell Nanosheets as Advanced Anode Materials for High-Performance Lithium-Ion Half/Full Cells

Transition metal oxides have vastly limited practical application as electrode materials for lithium-ion batteries (LIBs) due to their rapid capacity decay. Here, a versatile strategy to mitigate the volume expansion and low conductivity of Fe₃ O₄ by coating a thin carbon layer on the surface of Fe₃ O₄ nanosheets (NSs) was employed. Owing to the 2D core-shell structure, the Fe₃ O₄ @C NSs exhibit significantly improved rate performance and cycle capability compared with bare Fe₃ O₄ NSs. After 200 cycles, the discharge capacity at 0.5 A g^-1 was 963 mA h g^-1 (93 % retained). Moreover, the reaction mechanism of lithium storage was studied in detail by ex situ XRD and HRTEM. When coupled with a commercial LiFePO₄ cathode, the resulting full cell retains a capacity of 133 mA h g^-1 after 100 cycles at 0.1 A g^-1 , which demonstrates its superior energy storage performance. This work provides guidance for constructing 2D metal oxide/carbon composites with high performance and low cost for the field of energy storage.

Fullerene C76 as a novel electrocatalyst for VO2+/VO2+ and chlorine evolution inhibitor in all-vanadium redox flow batteries

We report, for the first time, the superior electrocatalytic activity of fullerene C₇₆ towards VO²⁺/VO₂⁺ in all-vanadium redox flow batteries.

Nitrofullerene, a C60-based Bifunctional Additive with Smoothing and Protecting Effects for Stable Lithium Metal Anode

Practical applications of lithium metal anodes are gravely impeded by inhomogeneous lithium deposition, which results in dendrite growth. Electrolyte additives are proven to be effective in improving performance but usually serve only a single function. Herein, nitrofullerene is introduced as a bifunctional additive with a smoothing effect and forms a protective solid electrolyte interphase (SEI) layer on stable lithium metal anodes. By design, nitro-C₆₀ can gather on electrode protuberances via electrostatic interactions and then be reduced to NO₂^- and insoluble C₆₀. Next, the C₆₀ anchors on the uneven groove of the lithium surface, resulting in a homogeneous distribution of Li ions. Finally, NO₂^- anions can react with metallic Li to build a compact and stable SEI with high ion transport. With a 5 mM nitro-C₆₀ additive, Li-Li symmetric cells show superior cycle stability in both carbonate and ether electrolytes, Li-sulfur batteries with a high cathode loading (10.6 mg cm^-2, 6 mAh cm^-2) can achieve improved cycle retention of 63.2% over 100 cycles in a carbonate electrolyte, and full cells paired with a high-areal-capacity LiNi_0.6Co_0.2Mn_0.2O₂ cathode (3.5 mAh cm^-2) exhibit a significantly enhanced cycle lifespan even under lean electrolyte conditions.

Facile Synthesis of Sn/Nitrogen-Doped Reduced Graphene Oxide Nanocomposites with Superb Lithium Storage Properties

Sn/Nitrogen-doped reduced graphene oxide (Sn@N-G) composites have been successfully synthesized via a facile method for lithium-ion batteries. Compared with the Sn or Sn/graphene anodes, the Sn@N-G anode exhibits a superb rate capability of 535 mAh g⁻¹ at 2C and cycling stability up to 300 cycles at 0.5C. The improved lithium-storage performance of Sn@N-G anode could be ascribed to the effective graphene wrapping, which accommodates the large volume change of Sn during the charge–discharge process, while the nitrogen doping increases the electronic conductivity of graphene, as well as provides a large number of active sites as reservoirs for Li⁺ storage.

Upcycling of Electroplating Sludge into Ultrafine Sn@C Nanorods with Highly Stable Lithium Storage Performance

Sn-based anode materials have become potential substitutes for commercial graphite anode due to their high specific capacity and good safety. In this paper, ultrafine Sn nanoparticles embedded in nitrogen and phosphorus codoped porous carbon nanorods (Sn@C) are obtained by carbonizing bacteria that adsorb the Sn electroplating sludge extracting solution. The as-prepared Sn@C rod-shaped composite exhibits superior electrochemical Li-storage performances, such as a reversible capacity of approximate 560 mAh/g at 1 A/g and an ultralong cycle life exceeding 1500 cycles, with approximately no capacity decay. The ultrastable structure of the Sn@C was revealed using in situ transmission electron microscope at the nanoscale and indicated that the Sn@C composite could restrict the volume expansion of Sn nanoparticles during the lithiation/delithiation cycles. This work provides a new insight into addressing the electroplating sludge and designing novel lithium ion battery anodes.

Enhanced Interfacial Kinetics of Carbon Monolith Boosting Ultrafast Na-Storage

Slow ion kinetics of negative electrode materials is the main factor of limiting fast charge and discharge of batteries. Sluggish Na⁺ kinetics property leads to large electrode polarization, resulting in poor rate and cyclic performances. Herein, an electrode of ultrasmall tin nanoparticles decorated in N, S codoped carbon monolith (TCM) with exceptional high-rate capability and ultrastable cycling behavior for Na-storage is reported. The resulted TCM electrode exhibits an extremely high retention of 96% initial charge capacity after 500 cycles at a current density of 500 mA g^-1 . Significantly, when the current density is elevated to an ultrahigh rate of 5000 mA g^-1 , a high reversible capacity of 228 mAh g^-1 after the 2000th cycle is still maintained. More importantly, the stable and fast Na-storage of TCM is investigated and understood by experimental characterizations and kinetics calculations, including interfacial ion/electron transport behavior, ion diffusion, and quantitative pseudocapacitive analysis. These investigations elucidate that the TCM shows improved ion/electron conductivity and enhanced interfacial kinetics. An entirely new perspective to deep insights into the fast ion/electron transport mechanisms revealed by interfacial kinetics of sodiation/desodiation, which contributes to the profound understanding for developing fast charging/discharging and long-term stable electrodes in sodium-ion batteries, is provided.

Scalable Fabrication of Core-Shell Sb@Co(OH)2 Nanosheet Anodes for Advanced Sodium-Ion Batteries via Magnetron Sputtering

Antimony (Sb) has captured extensive attention as a promising anode for sodium-ion batteries (SIBs) due to its high theoretical capacity and moderate sodiated potential but is held back from practical applications owing to its pulverization induced by dramatic volumetric variations during the (de)sodiation process. Herein, we report a core-shell Sb@Co(OH)₂ nanosheet anode fabricated via magnetron sputtering Sb onto the mass-productive Co(OH)₂ substrate anchored on stainless-steel mesh, which is scalable and suitable for flow-line production. In SIBs, the Sb@Co(OH)₂ anode displays superior rate performance (383.5 mAh/g at 30 A/g), high discharge capacity, and excellent stability. Compared with the sputtered Sb film electrode, the improved performance of the core-shell Sb@Co(OH)₂ nanosheet anode can be attributed to the open framework of the Co(OH)₂ substrate, not only accelerating the ion and electron transfer but also serving as the buffer for alleviating the volumetric variation and the supporting scaffold for prohibiting the aggregation. More importantly, the (de)sodiation mechanism of the Sb@Co(OH)₂ anode was explored by operando ( in situ) X-ray diffraction, and the similar alloying-dealloying processes (Sb ↔ Na _xSb ↔ Na₃Sb) for the 1st, 13th, and 30th cycles illustrate the excellent stability of the electrode.

Low Interface Energies Tune the Electrochemical Reversibility of Tin Oxide Composite Nanoframes as Lithium-Ion Battery Anodes

The conversion reaction of lithia can push up the capacity limit of tin oxide-based anodes. However, the poor reversibility limits the practical applications of lithia in lithium-ion batteries. The latest reports indicate that the reversibility of lithia has been appropriately promoted by compositing tin oxide with transition metals. The underlying mechanism is not revealed. To design better anodes, we studied the nanostructured metal/Li₂O interfaces through atomic-scale modeling and proposed a porous nanoframe structure of Mn/Sn binary oxides. The first-principles calculation implied that because of a low interface energy of metal/Li₂O, Mn forms smaller particles in lithia than Sn. Ultrafine Mn nanoparticles surround Sn and suppress the coarsening of Sn particles. Such a composite design and the resultant interfaces significantly enhance the reversible Li-ion storage capabilities of tin oxides. The synthesized nanoframes of manganese tin oxides exhibit an initial capacity of 1620.6 mA h g^-1 at 0.05 A g^-1. Even after 1000 cycles, the nanoframe anode could deliver a capacity of 547.3 mA h g^-1 at 2 A g^-1. In general, we demonstrated a strategy of nanostructuring interfaces with low interface energy to enhance the Li-ion storage capability of binary tin oxides and revealed the mechanism of property enhancement, which might be applied to analyze other tin oxide composites.