High Reversible Capacity Research Articles

Synthesis of Sb2Se3@PPy nanorod composite as cathode material for aluminum batteries

Aluminum batteries (ABs) are a promising alternative to lithium-ion batteries (LIBs) in the future. The development of aluminum batteries(ABs) is closely related to their cathode material. In this paper, we successfully designed and prepared a nanorod structure Sb2Se3@PPy as cathode material for ABs. It exhibits a high reversible capacity of 302 mAh/g at 0.2 A/g, and the capacity is maintained at about 210 mAh/g after 50 cycles. In addition, the electrochemical reaction mechanism and kinetic process of Sb2Se3@PPy were studied. The results showed that the PPy coating layer reduced the volume change of Sb2Se3, prevented irreversible deformation, enhanced the structural stability and electronic conductivity.

Crystalline MnCO3@Amorphous MnOx Composite as Cathode Material for High-Performance Aqueous Zinc-Ion Batteries.

Rechargeable aqueous zinc-ion batteries (RAZIBs) have received extensive attention because of their advantages of low cost, high safety, and nontoxicity. However, problems such as dissolution of the active cathode material, dendrites/passivation of the zinc anode, and slow reaction kinetics hindered their further applications. In this work, a crystalline/amorphous composite-type material composed of crystalline MnCO3 and amorphous MnOx was prepared and used as the cathode material for RAZIBs. The MnCO3@amorphous MnOx (MnCO3@A-MnOx) composite possesses the merits of both the pure crystalline phase of MnCO3 and the amorphous phase of MnOx, which can deliver better electrochemical performance than the corresponding single component in repeated cycles. In addition, crystalline MnCO3 undergoes a complex phase transition to the active MnO2 during the first charge process, providing the composite with a stable structure and additional electrochemical capacity. The electrochemical measurement results indicate that the MnCO3@A-MnOx electrode can display high reversible discharge capacity at 0.1 A g-1, excellent rate performance at 5.0 A g-1, and long cycling stability over 2000 cycles, showing great potential as a cathode material for high-performance RAZIBs.

Solid-state lithium batteries composed of hematite and oxide electrolyte

As Li-ion battery anode materials, two types of hematite (Fe2O3(big), Fe2O3(ultrafine)) were evaluated by using liquid electrolyte and oxide-based solid electrolyte. Although the anode using Fe2O3(ultrafine) with larger specific surface area showed a high initial reversible capacity in the liquid-electrolyte cell, there was a steep capacity decay in the cycling test. In the solid-electrolyte cell, we obtained very low reversible capacities of 40 mA h g−1 for the anode using Fe2O3(big) with smaller specific surface area. In contrast, the capacity of Fe2O3(ultrafine) anode was as high as 400 mA h g−1 at the 20th cycle. This is the first demonstration of charge–discharge reactions for Fe2O3 anode in oxide-based solid-state batteries. The Fe2O3(ultrafine) particles were dispersed relatively uniformly between solid electrolyte in the active layer, suggesting that the contact area between Fe2O3 and solid electrolyte becomes large. Consequently, Fe2O3(ultrafine) could benefit from larger contact area delivering the suitable reaction site for Li+ to improve the anode performance.

Selective Lattice Doping Enables a Low-Cost, High-Capacity and Long-Lasting Potassium Layered Oxide Cathode for Potassium and Sodium Storage.

Layered transition metal oxides are highly promising host materials for K ions, owing to their high theoretical capacities and appropriate operational potentials. To address the intrinsic issues of KxMnO2 cathodes and optimize their electrochemical properties, a novel P3-type oxide doped with carefully chosen cost-effective, electrochemically active and multi-functional elements is proposed, namely K0.57Cu0.1Fe0.1Mn0.8O2. Compared to the pristine K0.56MnO2, its reversible specific is increased from 104 to 135 mAh g-1. In addition, the Cu and Fe co-doping triples the capacity under high current densities, and contributes to long-term stability over 500 cycles with a capacity retention of 68 %. Such endeavor holds the potential to make potassium-ion batteries particularly competitive for application in sustainable, low-cost, and large-scale energy storage devices. In addition, the cathode is also extended for sodium storage. Facilitated by the interlayer K ions that protect the layered structure from collapsing and expand the diffusion pathway for sodium ions, the cathode shows a high reversible capacity of 144 mAh g-1, fast kinetics and a long lifespan over 1000 cycles. The findings offer a novel pathway for the development of high-performance and cost-effective sodium-ion batteries.

Regulating Sulfur Redox Kinetics by Coupling Photocatalysis for High-Performance Photo-Assisted Lithium-Sulfur Batteries.

Challenges such as shuttle effect have hindered the commercialization of lithium-sulfur batteries (LSBs), despite their potential as high-energy-density storage devices. To address these issues, we explore the integration of solar energy into LSBs, creating a photo-assisted lithium-sulfur battery (PA-LSB). The PA-LSB provides a novel and sustainable solution by coupling the photocatalytic effect to accelerate sulfur redox reactions. Herein, a perovskite quantum dot-loaded MOF material serves as a cathode for the PA-LSB, creating built-in electric fields at the micro-interface to extend the lifetime of photo-generated charge carriers. The band structure of the composite material aligns well with the electrochemical reaction potential of lithium-sulfur, enabling precise regulation of polysulfides in the cathode of the PA-LSB system. This is attributed to the selective catalysis of the liquid-solid reaction stage in the lithium-sulfur electrochemical process by photocatalysis. These contribute to the outstanding performance of PA-LSBs, particularly demonstrating a remarkably high reversible capacity of 679 mAh g-1 at 5 C, maintaining stable cycling for 1500 cycles with the capacity decay rate of 0.022 % per cycle. Additionally, the photo-charging capability of the PA-LSB holds the potential to compensate for non-electric energy losses during the energy storage process, contributing to the development of lossless energy storage devices.

Regulating Sulfur Redox Kinetics by Coupling Photocatalysis for High‐Performance Photo‐Assisted Lithium‐Sulfur Batteries

AbstractChallenges such as shuttle effect have hindered the commercialization of lithium‐sulfur batteries (LSBs), despite their potential as high‐energy‐density storage devices. To address these issues, we explore the integration of solar energy into LSBs, creating a photo‐assisted lithium‐sulfur battery (PA‐LSB). The PA‐LSB provides a novel and sustainable solution by coupling the photocatalytic effect to accelerate sulfur redox reactions. Herein, a perovskite quantum dot‐loaded MOF material serves as a cathode for the PA‐LSB, creating built‐in electric fields at the micro‐interface to extend the lifetime of photo‐generated charge carriers. The band structure of the composite material aligns well with the electrochemical reaction potential of lithium‐sulfur, enabling precise regulation of polysulfides in the cathode of the PA‐LSB system. This is attributed to the selective catalysis of the liquid‐solid reaction stage in the lithium‐sulfur electrochemical process by photocatalysis. These contribute to the outstanding performance of PA‐LSBs, particularly demonstrating a remarkably high reversible capacity of 679 mAh g−1 at 5 C, maintaining stable cycling for 1500 cycles with the capacity decay rate of 0.022 % per cycle. Additionally, the photo‐charging capability of the PA‐LSB holds the potential to compensate for non‐electric energy losses during the energy storage process, contributing to the development of lossless energy storage devices.

Sulphonated coal tar pitch as a carbon source to develop the storage capacity of Fe2O3@C materials

Utilizing metal oxides as substitutes for carbon anodes is imperative in advancing LIBs. Recently, the researchers regarding to the Fe2O3 have become very popular owing to its advantages such as a high theoretical capacity (1007 mAh g−1), cost-effectiveness and sustainability. In our present studies, the Fe2O3@SCTPC (Fe2O3 nanosphere coated by carbons which are obtained by the carbonizations using the sulphonated coal tar pitches) materials are firstly and successfully fabricated by a one-step hydrothermal method using the Fe(NO3)3·9 H2O and sulphonated coal tar pitches (SCTPs). An intriguing observation is that the nanosphere Fe2O3 is encapsulated by carbons with a core-shell structure. This specific core-shell structure effectively mitigates the volume expansion of Fe2O3, and exhibits a notable enhancement in conductivity. Thanks to this unique structure, the Fe2O3@SCTPC electrode has a maximum capacity of 1106.74 mAh g−1 after 100 cycles at a current density of 0.1 A g−1 and a high reversible specific capacity of 373.5 mAh g−1 after 500 cycles at a current density of 2 A g−1, when it is used as an anode material for Li-ion battery. These results suggest that adjusting the structures of carbons is crucial to develop the potential storage capacity of the covered Fe2O3.

A new FeS2/N-C nanoparticle from NH2-MIL-101 for high performance lithium ion batteries

Among multitudinous lithium storage electrode materials, transition metal sulfides have attracted widespread attention because of high theoretical capacity and wide availability. However, these anodes still suffer poor capacity retention and limited cycle life. Metal organic frameworks (MOFs) are important precursors for fabricating functional materials for energy conversion and storage. A study of their derivatization process is of great significance for the design of materials with specific functional properties. In this paper, a new FeS2/N-C nanoparticle is synthesized by calcination strategy from NH2-MIL-101 prepared by solvothermal method. Due to the coordination effect of nitrogen-doped carbon and special particle morphology, the synthesized FeS2/N-C nanoparticles have superior cycling stability and high reversible capacity. This work provides a better understanding of the carbonization process of MOFs and reveals the effect of N-doped and MOF synthesis time on transition metal sulfides.

Metal-organic framework cobalt gallate derived high-voltage carbon coated lithium cobalt oxide cathode and porous carbon supported cobalt oxide anode materials for superior lithium-ion storage

Exploring innovative green synthesis strategies for both cathode and anode materials with improved lithium-ion storage capabilities is of great importance in developing advanced lithium-ion batteries. In this work, a metal-organic framework (MOF) typed sample cobalt gallate (Co-GA), prepared by the direct redox coprecipitation reaction using gallic acid (GA) molecules and metallic cobalt (Co) foils in mild hydrothermal condition, is employed as a precursor for engineering electrode materials for lithium-ion batteries with high atomic efficiency and low environmental impact. Taking the advantages of the unique microstructure and chemical composition of MOF materials, the Co-GA precursor can be easily converted to a rod-like porous carbon framework confined cobalt oxide nanoparticle anode material (Co3O4/RPC) and a thin carbon layer coated nanosized lithium cobalt oxide (LiCoO2) cathode material (LCO/C), respectively, by simply changing the solid-state reaction conditions. In half-cells with metallic lithium as counter electrode, the LCO/C cathode delivers a stable reversible capacity of 189.33 mAh·g−1 after 100 cycles at 200 mA·g−1 and 128.61 mAh·g−1 after 800 cycles at 1000 mA·g−1 in the voltage range of 3.0–4.6 V, while the Co3O4/RPC anode shows a high reversible capacity of 1081.33 mAh·g−1 after 100 cycles at 200 mA·g−1 and 901.09 mAh·g−1 after 400 cycles at 1000 mA·g−1. This work provides a new perspective for green engineering of both anodic and cathodic materials with enhanced lithium-ion storage performances derived from MOF-typed precursors.

Vacancy-Defect Ternary Topological Insulators Bi2Se2Te Encapsulated in Mesoporous Carbon Spheres for High Performance Sodium Ion Batteries and Hybrid Capacitors.

Ternary topological insulators have attracted worldwide attention because of their broad application prospects in fields such as magnetism, optics, electronics, and quantum computing. However, their potential and electrochemical mechanisms in sodium ion batteries (SIBs) and hybrid capacitors (SIHCs) have not been fully studied. Herein, a composite material comprising vacancy-defects ternary topological insulator Bi2Se2Te encapsulated in mesoporous carbon spheres (Bi2Se2Te@C) is designed. Bi2Se2Te with ample vacancy-defects has a wide interlayer spacing to enable frequent insertion/extraction of Na+ and boost reaction kinetics within the electrode. Meanwhile, the Bi2Se2Te@C with optimized yolk-shell structure can buffer the volume variation without breaking the outer protective carbon shell, ensuring structural stability and integrity. As expected, the Bi2Se2Te@C electrode delivers high reversible capacity and excellent rate capability in half SIB cells. Various electrochemical analyses and theoretical calculations manifest that Bi2Se2Te@C anode confirms the synergistic effect of ternary chalcogenide systems and suitable void space yolk-shell structure. Consequently, the full cells of SIB and SIHC coupled with Bi2Se2Te@C anode exhibit good performance and high energy/power density, indicating its widespread practical applications. This design is expected to offer a reliable strategy for further exploring advanced topological insulators in Na+-based storage systems.

Engineering Oxygen Vacancies in In2O3 with Enhanced Polysulfides Immobilization and Selective Catalytic Capability.

Lithium-sulfur (Li-S) battery is identified as an ideal candidate for next-generation energy storage systems in consideration of its high theoretical energy density and abundant sulfur resources. However, the shuttling behavior of soluble polysulfides (LiPSs) and their sluggish reaction kinetics severely limit the practical application of the current Li-S battery. In this work, a series of In2O3 nanocubes with different oxygen vacancy concentrations are designed and prepared via a facile self-template method. The introduced oxygen vacancy on In2O3 can effectively rearrange the charge distribution and enhance sulfiphilic property. Moreover, the In2O3 with high oxygen vacancy concentration (H-In2O3) can slightly slow down the solid-liquid conversion process and significantly accelerate the liquid-solid conversion process, thus reducing the accumulation of LiPSs in electrolyte and inhibiting the shuttle effect. Contributed by the unique selective catalytic capability, the prepared H-In2O3 exhibits excellent electrochemical performance when used as sulfur host. For instance, a high reversible capacity of 609 mAh g-1 is obtained with only 0.044% capacity decay per cycle over 1000 cycles at 1.0C. This work presents a typical example for designing advanced sulfur hosts, which is crucial for the commercialization of Li-S battery.

Enhancing the electrochemical properties of TiNb2O7 anodes with SP-CNT binary conductive agents for both liquid and solid state lithium ion batteries.

A high performance oxide composite electrode is obtained with a two-step solid state calcined titanium niobium oxide TiNb2O7 (TNO) anode and super P-carbon nanotube (SP-CNT) binary conductive agents. The solid state synthesized TNO-0.2C (the proportion of CNTs in the binary conductive agent is 20% wt) anode exhibits a high reversible discharge capacity of 278.6 mA h g-1 at 0.5C, a competitive rate capability with reported works that employed wet chemical methods at moderate rates (178.1 mA h g-1 at 10C), and an excellent capacity retention of 92.2% after 200 cycles at 1.5C/1.5C. The enhancement in electrochemical properties of the TNO-0.2C anode is mainly attributed to the combination of the short range and long range conductive agents in the SP-CNT binary conductive system, which guarantees an efficient electronic conductive network. The Li|Li1.3Al0.3Ti1.7(PO4)3 composite polymer electrolyte (LATPCPEs)|TNO-0.2C solid state batteries are also assembled, which deliver a high initial reversible discharge capacity of 241.3 mA h g-1 at 1C and a good capacity retention rate of 93% after 50 cycles. This work provides an efficient way to improve the electrochemical properties of TNO anodes in lithium ion batteries, especially for solid state batteries.

Regulation of fiber surface nucleation kinetics via ordered nitrogen-rich carbon dots

Three dimensional (3D) carbon-based current collectors have attracted much attentions as host for Li metal anodes (LMAs) owing to their lightweight, flexible, and wide sources etc. However, the lithiophobic nature of carbon makes it difficult to achieve low nucleation overpotential and dendrite-free Li deposition. Herein, carbon dots (CDs) with nitrogen (N)-rich were introduced to modify carbonized cotton fiber (CCF) coated by reduced graphene oxide (CD@RGCCF). Coating graphene oxide (GO) increases the active site of cotton fiber (CF), which facilitates the growth of CDs on the surface of CF fiber. The introduction of ordered structure CDs drives fast migration of Li+ in the “highway-like” channels and induces the uniform nucleation of Li in the initial stage. As a result, the obtained CD@RGCCF decreases the nucleation overpotential of Li, and achieves dendrite-free Li deposition. the CD@RGCCF|Li half cells exhibit extending cycling life over 5000 h with a voltage hysteresis of 10.5 mV at 2 mA cm−2. As coupled with the LiFePO4 (LFP), the Li@CD@RGCCF||LFP composite anode enables a high reversible specific capacity and improved cycle stability. This work provides a low-cost modification method for carbon substrate to realize dendritic-free LMAs.

Synergistic Engineering of CoO/MnO Heterostructures Integrated with Nitrogen-Doped Carbon Nanofibers for Lithium-Ion Batteries.

The integration of heterostructures within electrode materials is pivotal for enhancing electron and Li-ion diffusion kinetics. In this study, we synthesized CoO/MnO heterostructures to enhance the electrochemical performance of MnO using a straightforward electrostatic spinning technique followed by a meticulously controlled carbonization process, which results in embedding heterostructured CoO/MnO nanoparticles within porous nitrogen-doped carbon nanofibers (CoO/MnO/NC). As confirmed by density functional theory calculations and experimental results, CoO/MnO heterostructures play a significant role in promoting Li+ ion and charge transfer, improving electronic conductivity, and reducing the adsorption energy. The accelerated electron and Li-ion diffusion kinetics, coupled with the porous nitrogen-doped carbon nanofiber structure, contribute to the exceptional electrochemical performance of the CoO/MnO/NC electrode. Specifically, the as-prepared CoO/MnO/NC exhibits a high reversible specific capacity of 936 mA h g-1 at 0.1 A g-1 after 200 cycles and an excellent high-rate capacity of 560 mA h g-1 at 5 A g-1, positioning it as a competitive anode material for lithium-ion batteries. This study underscores the critical role of electronic and Li-ion regulation facilitated by heterostructures, offering a promising pathway for designing transition metal oxide-based anode materials with high performances for lithium-ion batteries.

Electrochemical Restructuring Driven Catalytic Cycle of Bi-Based Heterojunctions for High-Performance Lithium-Sulfur Batteries.

Restructuring is an important phenomenon in catalytic reactions. Conversion-type materials with suitable redox potential may undergo in situ electrochemically driven restructurings and induce highly active catalytic sites in a working lithium-sulfur battery. Herein, driven by the electrochemical conversion reaction of BiVO4, a reversible catalytic cycle of Bi/amorphous Li3VO4 (a-Li3VO4) and Bi2S3/a-Li3VO4 heterojunctions is constructed, which targets the oxidation of Li2S and the conversion of polysulfide, respectively. The heterostructures and electrochemically driven size confinement provide abundant sites for shuttle restraining and sulfur conversion. Especially, the p-block Bi and Bi2S3 could dramatically reduce the conversion energy barriers of Li2S and polysulfide by virtue of the p-p orbital hybridization, promoting bidirectional reactions of the sulfur cathode. As a result, the corresponding sulfur cathode possesses a high reversible capacity of 7.5 mAh cm-2 after 120 cycles under a high sulfur loading of 10.3 mg cm-2 with a current density of 0.38 mA cm-2. This study furnishes a feasible scheme to obtain highly effective catalysts for bidirectional sulfur redox by utilizing the electrochemically induced restructuring.

Engineering a Low-Strain Si@TiSi2@NC Composite for High-Performance Lithium-Ion Batteries.

The huge volume expansion/contraction of silicon (Si) during the lithium (Li) insertion/extraction process, which can lead to cracking and pulverization, poses a substantial impediment to its practical implementation in lithium-ion batteries (LIBs). The development of low-strain Si-based composite materials is imperative to address the challenges associated with Si anodes. In this study, we have engineered a TiSi2 interface on the surface of Si particles via a high-temperature calcination process, followed by the introduction of an outermost carbon (C) shell, leading to the construction of a low-strain and highly stable Si@TiSi2@NC composite. The robust TiSi2 interface not only enhances electrical and ionic transport but also, more critically, significantly mitigates particle cracking by restraining the stress/strain induced by volumetric variations, thus alleviating pulverization during the lithiation/delithiation process. As a result, the as-fabricated Si@TiSi2@NC electrode exhibits a high initial reversible capacity (2172.7 mAh g-1 at 0.2 A g-1), superior rate performance (1198.4 mAh g-1 at 2.0 A g-1), and excellent long-term cycling stability (847.0 mAh g-1 after 1000 cycles at 2.0 A g-1). Upon pairing with LiNi0.6Co0.2Mn0.2O2 (NCM622), the assembled Si@TiSi2@NC||NCM622 pouch-type full cell exhibits exceptional cycling stability, retaining 90.1% of its capacity after 160 cycles at 0.5 C.

Li-ion storage chemistry of metal layers influences on metal oxides

A suitable current collector is a critical criterion for attaining high areal capacity in lithium batteries (LIBs). Here, we discover that the transition metal foam-type current collectors and their corresponding active materials upon a simple oxidation process, enable us to design a strategy for controlling the thickness of active materials toward achieving high areal capacity LIBs. Taking nickel foam (NiF) as a case study, we demonstrated that by calcining it in the air at different temperatures of 500 ℃, 600 ℃, 700 ℃, and 800 ℃, the electrodes exhibit distinct physical properties such as the thickness of active material layers, mechanical strength, and electrochemical properties including the rate capabilities, pseudocapacitive contribution, and lithium-ion diffusion. Ultimately, the optimized anode calcined at 700 °C (700-NiO@NiF) maintains a high reversible areal capacity of 7.6 mAh cm−2@0.4 mA cm−2, and 2.0 mAh cm−2 after 200 cycles@3.0 mA cm−2, We further verify that both cobalt foam and copper foam exhibited similar features like that of NiF by tuning their annealing temperatures, creating more opportunities for maximizing the areal capacity of LIBs.

From bulky Si to porous medium entropy alloy: Enabling highly efficient Li storage via the simultaneous reconstruction of microstructure and component

We show here that the Li-storage performance of Si anode can be substantially improved by engineering a multilevel nanoporous SiGeTiZnCuAl medium entropy alloy (NP-MEA). The NP-MEA is directly engineered through a corrosion-driven phase and structure simultaneous reconstruction by partially etching Al and Zn from the multi-element master alloy. The unique multi-elemental interactions can revolutionize the chemical microenvironment, and thus stabilize the structure and impel the transportation of the electrons and ions. The metallic sponge offers multilevel pore channels for electrolyte permeation and ample space for volume change accommodation, abundant accessible active sites for lithiation/delithiation, as well as the rigid skeleton for expediting the electron transportation and stabilizing the structure. Benefiting from the synergy of component and structure, the NP-MEA delivers a high reversible capacity of 646.1 mAh g−1 after 500 cycles at a current density of 2 A g−1.

Polymer hetero-electrolyte enabled solid-state 2.4-V Zn/Li hybrid batteries

The high redox potential of Zn0/2+ leads to low voltage of Zn batteries and therefore low energy density, plaguing deployment of Zn batteries in many energy-demanding applications. Though employing high-voltage cathode like spinel LiNi0.5Mn1.5O4 can increase the voltages of Zn batteries, Zn2+ ions will be immobilized in LiNi0.5Mn1.5O4 once intercalated, resulting in irreversibility. Here, we design a polymer hetero-electrolyte consisting of an anode layer with Zn2+ ions as charge carriers and a cathode layer that blocks the Zn2+ ion shuttle, which allows separated Zn and Li reversibility. As such, the Zn‖LNMO cell exhibits up to 2.4 V discharge voltage and 450 stable cycles with high reversible capacity, which are also attained in a scale-up pouch cell. The pouch cell shows a low self-discharge after resting for 28 days. The designed electrolyte paves the way to develop high-voltage Zn batteries based on reversible lithiated cathodes.

Highly Stable Polyaniline-Based Cathode Material Enabled by Phosphorene for Zinc-Ion Batteries with Superior Specific Capacity and Cycle Life.

Aqueous zinc-ion batteries (ZIBs) are regarded as a type of promising energy-storage device because of their high safety and low cost, and polyaniline (PANI) is normally employed as a cathode material for ZIBs owing to its unique electrochemical properties and high environmental stability. However, a low specific capacity and a short cycle life limit the development and applications of PANI-based electrodes. Herein, we have developed a novel type of highly stable PANI-based cathode material enabled by phosphene (PR) for aqueous Zn-PANI batteries through in situ chemical oxidative polymerization. The introduction of PR nanoflakes not only inhibits the degradation of PANI and generates more active sites for Zn2+ storage but also enables a synergistic effect of the Zn2+ insertion/extraction and P-Zn alloying reaction. This promotes a high reversible specific capacity of 240.2 mAh g-1 at 0.2 A g-1 and excellent rate performance for the PR/PANI nanocomposite cathode material. Compared to the pristine PANI cathode material, the PR/PANI nanocomposite cathode material is more suitable for the Zn-PANI battery, thanks to its higher specific capacity and better cycle stability. This study provides an innovative approach for developing the next generation of reliable PR-based electrode materials for aqueous energy-storage devices.