Charge Storage Research Articles

Mechanically and Electrically Stable Hybrid Aerogels as Free‐Standing Anodes for High‐Capacity Lithium‐Ion Battery

Molybdenum disulfide (MoS2) is a promising alternative to graphite anodes in battery materials. Therefore, it is critical to scrutinize their structural stability and charge storage capacity during battery operation. Herein, freestanding electrodes consisting of MoS2‐incorporated carbon nanotube aerogels are fabricated using a simple yet scalable hydrothermal method, as used in lithium‐ion batteries. The outer nitrogen‐doped graphitic carbon (NGr) layers support efficient charge transport, even under a substantial compressive environment, and improve the structural integrity, showing significant improvements in battery performance, such as a high rate capacity of 820 mAh g−1 at the current density of 5 A g−1 and 94% capacity retention after 170 cycles (1170 mAh g−1 at 1 A g−1 after 170 cycles), even in the absence of polymer binders and conductive additives. The resulting NGr/MoS2/single‐walled carbon nanotubes freestanding electrodes have great potential to increase the volumetric and gravimetric energy density of batteries.

Comparative Study of Chemical Activation and Physical Activation Approach to Optimize Biomass-Based Doped Carbons for Energy Applications

Abstract Two approaches have been utilized to optimize the energy storage characteristics of doped carbon materials derived from Lignosol, a biomass product, to address the rising energy demand issues. Herein, phosphorus and nitrogen co-doped carbon (PNDC) materials with varying doping agent volumes were synthesized by utilizing microwave irradiation. Chemical activation and physical activation were employed to enhance these materials’ characteristics. Chemical activation was performed in a one-pot, single-step process, rather than a traditional multi-step protocol, using small amounts of potassium hydroxide. Furthermore, the physical activation method required multiple steps: doped carbon was prepared via microwave, exposed to water, filtered, frozen and then dried. With this, the expansion properties of water at freezing temperatures were exploited to alter the materials’ surface characteristics. All materials were characterized and compared for their physicochemical properties. All defect ratios supported the presence of doping. Additional results revealed that both chemical and physical activation approaches effectively modify the topographical features as well as the electrochemical activity (charge storage) of the doped carbon materials. The chemically activated doped carbon exhibited the highest resulting surface area of 1352 m2/g and a specific capacitance value of 347 F g-1 with excellent cycling stability as compared to other similarly synthesized materials.

Biomass-Derived Carbon Materials for Advanced Metal-Ion Hybrid Supercapacitors: A Step Towards More Sustainable Energy

Modern research has made the search for high-performance, sustainable, and efficient energy storage technologies a main focus, especially in light of the growing environmental and energy-demanding issues. This review paper focuses on the pivotal role of biomass-derived carbon (BDC) materials in the development of high-performance metal-ion hybrid supercapacitors (MIHSCs), specifically targeting sodium (Na)-, potassium (K)-, aluminium (Al)-, and zinc (Zn)-ion-based systems. Due to their widespread availability, renewable nature, and exceptional physicochemical properties, BDC materials are ideal for supercapacitor electrodes, which perfectly balance environmental sustainability and technological advancement. This paper delves into the synthesis, functionalization, and structural engineering of advanced biomass-based carbon materials, highlighting the strategies to enhance their electrochemical performance. It elaborates on the unique characteristics of these carbons, such as high specific surface area, tuneable porosity, and heteroatom doping, which are pivotal in achieving superior capacitance, energy density, and cycling stability in Na-, K-, Al-, and Zn-ion hybrid supercapacitors. Furthermore, the compatibility of BDCs with metal-ion electrolytes and their role in facilitating ion transport and charge storage mechanisms are critically analysed. Novelty arises from a comprehensive comparison of these carbon materials across metal-ion systems, unveiling the synergistic effects of BDCs’ structural attributes on the performance of each supercapacitor type. This review also casts light on the current challenges, such as scalability, cost-effectiveness, and performance consistency, offering insightful perspectives for future research. This review underscores the transformative potential of BDC materials in MIHSCs and paves the way for next-generation energy storage technologies that are both high-performing and ecologically friendly. It calls for continued innovation and interdisciplinary collaboration to explore these sustainable materials, thereby contributing to advancing green energy technologies.

A Unified Charge Storage Mechanism to Rationalize the Electrochemical Behavior of Quinone-Based Organic Electrodes in Aqueous Rechargeable Batteries.

Due to their eco-sustainability and versatility, organic electrodes are promising candidates for large-scale energy storage in rechargeable aqueous batteries. This is notably the case of aqueous hybrid batteries that pair the low voltage of a zinc anode with the high voltage of a quinone-based (or analogue of quinone-based) organic cathode. However, the mechanisms governing their charge-discharge cycles remain poorly understood and are even a matter of debate and controversy. No consensus exists on the charge carrier in mild aqueous electrolytes, especially when working in an electrolyte containing a multivalent metal cation such as Zn2+. In this study, we comprehensively investigate the electrochemical reactivity of two model quinones, chloranil, and duroquinone, either diluted in solution or incorporated into carbon-based composite electrodes. We demonstrate that a common nine-member square scheme proton-coupled electron transfer mechanism allows us to fully describe and rationalize their electrochemical behavior in relation to the pH and chemical composition of the aqueous electrolyte. Additionally, we highlight the crucial role played by the pKas associated with the reduced states of quinones in determining the nature of the charge carrier that compensates for the negative charges reversibly injected in the active material. Finally, contrary to the widely reported findings for Zn/organic batteries, we unequivocally establish that the predominant solid-state charge carriers in Zn2+-based mild aqueous electrolytes are not multivalent Zn2+ cations but rather protons supplied by the weakly acidic hexaaqua metal ions (i.e., [Zn(H2O)6]2+]).

Scanning Electrochemical Microscopy Meets Optical Microscopy: Probing the Local Paths of Charge Transfer Operando in Booster-Microparticles for Flow Batteries.

Understanding the oxidation/reduction dynamics of secondary microparticles formed from agglomerated nanoscale primary particles is crucial for advancing electrochemical energy storage technologies. In this study, the behavior of individual copper hexacyanoferrate (CuHCF) microparticles is explored at both global and local scales combining scanning electrochemical microscopy (SECM), for electrochemical interrogation of a single, but global-scale microparticle, and optical microscopy monitoring to obtain a higher resolution dynamic image of the local electrochemistry within the same particle. Chronoamperometric experiments unveil a multistep oxidation/reduction process with varying dynamics. On the one hand, the global SECM analysis enables quantifying the charge transfer as well as its dynamics at the single microparticle level during the oxidation/reduction cycles by a redox mediator in solution. These conditions allow mimicking the charge storage processes in these particles when they are used as solid boosters in redox flow batteries. On the other hand, optical imaging with sub-particle resolution allows the mapping of local conversion rates and state-of-charge within individual CuHCF particles. These maps reveal that regions of different material loadings exhibit varying charge storage capacities and conversion rates. The findings highlight the significance of porous nanostructures and provide valuable insights for designing more efficient energy storage materials.

Organic Solvent Boosts Charge Storage and Charging Dynamics of Conductive MOF Supercapacitors.

Conductive metal-organic frameworks (c-MOFs) and ionic liquids (ILs) have emerged as auspicious combinations for high-performance supercapacitors. However, the nanoconfinement from c-MOFs and high viscosity of ILs slow down the charging process. This hindrance can, however, be resolved by adding solvent. Here, we performed constant-potential molecular simulations to scrutinize the solvent impact on charge storage and charging dynamics of MOF-IL-based supercapacitors. We find conditions for >100% enhancement in capacity and ∼6 times increase in charging speed. These improvements were confirmed by synthesizing near-ideal c-MOFs and developing multiscale models linking molecular simulations to electrochemical measurements. Fundamentally, our findings elucidate that the solvent acts as an "ionophobic agent" to induce a substantial enhancement in charge storage, and as an "ion traffic police" to eliminate convoluted counterion and co-ion motion paths and create two distinct ion transport highways to accelerate charging dynamics. This work paves the way for the optimal design of MOF supercapacitors. This article is protected by copyright. All rights reserved.

Efficient Decoupled Electrolytic Water Splitting in Acid through Pseudocapacitive TiO2.

Water electrolysis remains a key component in the societal transition to green energy. Membrane electrolyzers are the state-of-the-art technology for water electrolysis, relying on 80°C operation in highly alkaline electrolytes, which is undesirable for many of the myriad end-use cases for electrolytic water splitting. Herein, an alternative water electrolysis process, decoupled electrolysis, is described which performed in mild acidic conditions with excellent efficiencies. Decoupled electrolysis sequentially performs the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), at the same catalyst. Here, H+ ions generated from the OER are stored through pseudocapacitive (redox) charge storage, and released to drive the HER. Here, decoupled electrolysis is demonstrated using cheap, abundant, TiO2 for the first time. To achieve decoupled acid electrolysis, ultra-small anatase TiO2 particles (4.5nm diameter) are prepared. These ultra-small TiO2 particles supported on a carbon felt electrode show a highly electrochemical surface area with a capacitance of 375Fg-1. When these electrodes are tested for decoupled water splitting an overall energy efficiency of 52.4% is observed, with excellent stability over 3000 cycles of testing. This technology can provide a viable alternative to membrane electrolyzers-eliminating the need for highly alkaline electrolytes and elevated temperatures.

Pectin Supercapacitor Applications

In today’s energy wars, the decrease in fossil fuels and the increase in pollution reuses the question of energy and clean merit production. For this reason, supercapacitor electrodes are available for supercapacitor applications, which are synthesized using biodegradable materials or hybrids by taking nature as an example. In synthesizing our example electrode pectin, we will examine the methods of obtaining pectin, which is abundant in nature and can be used effectively in terms of its physicochemical properties, by purification or synthesis methods. Supercapacitors are essential in storing energy with their fast charge/discharge properties. This includes using pectin and other materials in energy storage systems. We will present other materials preferred in supercapacitor applications and modified compilations of these applications. In conclusion; a porous material such as pectin has a large surface area. Materials with large surface areas are very suitable electrodes for charge storage in supercapacitor applications. If some problems in pectin production and electrical conductivity can be resolved, it will be a very suitable natural electrode material for supercapacitors.

Transfiguring energy with an advantageous supercapacitor integrating MoS2/carbon quantum dots bi‐composites into a high‐performance polypyrrole matrix for unprecedented efficiency

AbstractFor the first time, a simple one‐step in situ chemical polymerization technique is used to create a novel molybdenum disulphide/sulphonated carbon quantum dots (CQDs) and polypyrrole (MCP) nanocomposite that is extended for successful use in charge storage supercapacitor (SC) device. By inheriting qualities of excellent electrical conductivity of MoS2, CQDs and improved pseudocapacitive activity of polypyrrole (PPy), the MCP nanocomposite provides a suitable SC electrode material. 0.6 MCP nanocomposited three‐electrode system demonstrates 93.21% retention after 5000 cycles, and a maximum specific capacity of 2253 F/g at 2 mV/s with higher side of energy density as 106.06 Wh/kg along with a considerable power density as 180.28 W/kg. Using MCP as anode and an AC or activated charcoal electrode as cathode, a solid‐state asymmetric supercapacitor (ASC) was constructed. The fabricated device supplies a greater value of specific capacitance as 154.09 F/g at 100 mV/s and 175 F/g at 0.1 A/g, also evidenced superior energy density data as 126 Wh/kg along with an appreciable power density of 604.8 W/kg. After charging the ASC for 2 min, the light emitting diode shone for 5 min. The findings underpin that MCP is a potential electrode material that could be utilized as a better alternative in futuristic supercapacitor devices.

Facile design and enhanced interface polarization of CoFe-PBA/MXene towards microwave absorption, EMI shielding and energy storage

Electromagnetic properties and electrochemical properties of MXene hybrid materials have been one of the research hotspots. The development of high-performance MXene multifunctional composite materials is a challenging task. In this work, the free-stack CoFe-PBA/Ti3C2Tx MXene with lots of interfaces were fabricated using simple hydrothermal technology. The material can be used for microwave absorption, electromagnetic interference shielding and charge storage. Among them, CoFe-PBA/Ti3C2Tx MXene with the mass ratio of 1:3 achieved a maximum absorbing bandwidth of 4.72 GHz at 1.74 mm, covering the complete X-band; and certain electromagnetic shielding performance and good supercapacitance characteristics. The excellent electromagnetic attenuation characteristics derives from the intrinsic properties of charge transport and dielectric relaxation interface within CoFe-PBA/Ti3C2Tx MXene, and its rich active sites and carrier transport characteristics determine its good electrochemical performance. These results show that CoFe-PBA/Ti3C2Tx MXene is an excellent multifunctional material with potential application prospects in technical fields such as macrowave absorption, electromagnetic shielding and energy storage.

Rapid fabrication of binder free nickel cobalt oxide electrodes with dendritic nanostructure for electrochemical energy storage applications

A rapid and facile technique to synthesize nickel cobalt oxide electrodes by photothermal treatment of mixed organometallic precursor solution is reported. Using short and intense pulses of light from a xenon flash lamp, spray coated films are converted into porous nickel cobalt oxide electrodes with dendritic nanostructure. The electrode films fabricated in a few seconds show excellent energy storage properties as supercapacitor electrodes. Specific capacitance of up to 116 Fg−1 and capacitance retention of up to 75 % were observed in samples with low mass loading. Analysis of the cyclic voltammetry (CV) curves shows that capacitance is the dominating charge storage mechanism in these films. To study the effect of varying the mass loading in electrodes, double and triple layered electrodes were also studied. In films with high mass loading, the specific capacitance of the films decreased but areal capacitance continued to increase. A high areal capacitance of up to 243 mFcm−2 is observed in films with high mass loading. CV curve analysis of high mass loading electrodes further shows that in films with higher mass loading, the charge storage mechanism is a mix of capacitance and diffusion processes. The contribution of diffusion increased with increase in the mass loading of the electrodes. This study sheds light into the mechanism of charge storage in electrodes prepared by large-scale-amenable single step process of photonic curing which could be utilized to fabricate electrodes in industrial scale.

Electropolymerization of a Carbonyl-Modified Dihydropyrazine Derivative for Aqueous Zinc Batteries with Ultrahigh Cycling Stability.

The design of aqueous zinc-ion batteries (ZIBs) that have high specific capacity and long-term stability is essential for future large-scale energy storage systems. Cathode materials with extended π-conjugation and abundant active sites are desirable to enhance the charge storage performance and the cycling stability of the aqueous ZIB. Based on this concept, 6,9-dihydropyrazino[2,3-g]quinoxaline-2,3,7,8(1H,4H)-tetrone was chosen as the monomer to be electropolymerized onto carbon cloth (PDHPQ-Tetrone/CC). When used as the cathode material for aqueous ZIBs, an exceptional cycling life (>20,000 cycles) at a current density of 10 A g-1 was achieved, with the specific capacity maintained at 82.8% and with the Coulombic efficiency at around 100% throughout cycling. At the charge-discharge current density of 0.1 A g-1, the ZIB with PDHPQ-Tetrone/CC achieved a high specific capacity of 248 mAh g-1. Kinetic analyses showed that both surface-capacitive-controlled processes and semi-infinite diffusion-controlled processes contribute to the stored charge. The charge storage mechanism was investigated with ex situ characterizations and involves the redox processes of carbonyl/hydroxyl and amino/imino groups coupled with insertion and extraction of both Zn2+ and H+.

Zn-Doped MnO2 microflake pseudocapacitive cathode on Ni(OH)2/Ni-Foam substrate as a promising charge storage material

Zn-doped MnO2 microflakes cathode material on Ni(OH)2/Ni foam has been synthesized and characterized as well as tested its electrochemical performances in 3 M KOH solution. The present work varies the amounts of Zn dopant in MnO2 system to improve its capability in energy storage. Material identification has been simply confirmed with XRD, SEM, TEM, and XPS analysis. It is expected the Zn dopant will induce surface defects such as ZnMn2- or ZnMn0 and oxygen vacancy, leading to enhanced charge storage efficiency. In addition, XPS analysis reveals the existence of positively charged oxygen vacancy and the surface charge of ZnMn2- or ZnMn0 induce different surface oxidation states of Mn2+ and Mn4+. The oxidation states of Mn could accommodate the redox reactions involving ion adsorption and intercalation during pseudocapacitive charge and discharge processes. Substituting Zn into Mn sites is optimized with MnZn-1.5 which reaches a specific capacitance of 1601F/g at a 0.4 VAg/AgCl in KOH solution. This work demonstrates a promising material system for supercapacitor applications using Zn doping with a simple preparation process to support a large-scale application.

Nano-Spheroidal MnOx/C Nanomaterial with Battery-Like and Capacitive Charge Storage for Lithium-Ion Capacitors

Nano-Spheroidal MnOx/C Nanomaterial with Battery-Like and Capacitive Charge Storage for Lithium-Ion Capacitors

Organic Electrode Materials for Energy Storage and Conversion: Mechanism, Characteristics, and Applications.

ConspectusLithium ion batteries (LIBs) with inorganic intercalation compounds as electrode active materials have become an indispensable part of human life. However, the rapid increase in their annual production raises concerns about limited mineral reserves and related environmental issues. Therefore, organic electrode materials (OEMs) for rechargeable batteries have once again come into the focus of researchers because of their design flexibility, sustainability, and environmental compatibility. Compared with conventional inorganic cathode materials for Li ion batteries, OEMs possess some unique characteristics including flexible molecular structure, weak intermolecular interaction, being highly soluble in electrolytes, and moderate electrochemical potentials. These unique characteristics make OEMs suitable for applications in multivalent ion batteries, low-temperature batteries, redox flow batteries, and decoupled water electrolysis. Specifically, the flexible molecular structure and weak intermolecular interaction of OEMs make multivalent ions easily accessible to the redox sites of OEMs and facilitate the desolvation process on the redox site, thus improving the low-temperature performance, while the highly soluble nature enables OEMs as redox couples for aqueous redox flow batteries. Finally, the moderate electrochemical potential and reversible proton storage and release of OEMs make them suitable as redox mediators for water electrolysis. Over the past ten years, although various new OEMs have been developed for Li-organic batteries, Na-organic batteries, Zn-organic batteries, and other battery systems, batteries with OEMs still face many challenges, such as poor cycle stability, inferior energy density, and limited rate capability. Therefore, previous reviews of OEMs mainly focused on organic molecular design for organic batteries or strategies to improve the electrochemical performance of OEMs. A comprehensive review to explore the characteristics of OEMs and establish the correlation between these characteristics and their specific application in energy storage and conversion is still lacking.In this Account, we initially provide an overview of the sustainability and environmental friendliness of OEMs for energy storage and conversion. Subsequently, we summarize the charge storage mechanisms of the different types of OEMs. Thereafter, we explore the characteristics of OEMs in comparison with conventional inorganic intercalation compounds including their structural flexibility, high solubility in the electrolyte, and appropriate electrochemical potential in order to establish the correlations between their characteristics and potential applications. Unlike previous reviews that mainly introduce the electrochemical performance progress of different organic batteries, this Account specifically focuses on some exceptional applications of OEMs corresponding to the characteristics of organic electrode materials in energy storage and conversion, as previously published by our groups. These applications include monovalent ion batteries, multivalent ion batteries, low-temperature batteries, redox flow batteries with soluble OEMs, and decoupled water electrolysis employing organic electrodes as redox mediators. We hope that this Account will make an invaluable contribution to the development of organic electrode materials for next-generation batteries and help to unlock a world of potential energy storage applications.

Deciphering the storage mechanism of biochar anchored with different morphology Mn3O4 as advanced anode material for lithium-ion batteries

Biochar is regarded as a promising lithium-ion batteries anode material, owing to its high cost-effectiveness. However, the poor specific capacity and cycling stability have limited its practical applications. A straightforward and cost-efficient solvothermal method is presented for synthesizing Mn3O4/biochar composites in this study. By adjusting solvothermal temperatures, Mn3O4 with different morphology is prepared and anchored on the biochar surface (MKAC-T) to improve the electrochemical performance. Due to the morphological effect of nanospherical Mn3O4 on the biochar surface, the MKAC-180 anode material demonstrates outstanding reversible capacity (992.5 mAh/g at 0.2 A/g), significant initial coulombic efficiency (61.1 %), stable cycling life (605.3 mAh/g at 1.0 A/g after 1000 cycles), and excellent rate performance (385.8 mAh/g at 1.6 A/g). Moreover, electro-kinetic analysis and ex-situ physicochemical characterizations are employed to illustrate the charge storage mechanisms of MKAC-180 anode. This study provides valuable insights into the “structure–activity relationship” between Mn3O4 microstructure and electrochemical performance for the Mn3O4/biochar composites, illuminating the industrial utilization of biomass carbon anode materials.

A Membrane-Free Rechargeable Seawater Battery Unlocked by Lattice Engineering.

Seawater batteries that directly utilize natural seawater as electrolytes are ideal sustainable aqueous devices with high safety, exceedingly low cost, and environmental friendliness. However, the present seawater batteries are either primary batteries or rechargeable half-seawater/half-nonaqueous batteries because of the lack of suitable anode working in seawater. Here, a unique lattice engineering to unlock the electrochemically inert anatase TiO2 anode to be highly active for the reversible uptake of multiple cations (Na+, Mg2+, and Ca2+) in aqueous electrolytes is demonstrated. Density functional theory calculationsfurther reveal the origin of the unprecedented charge storage behaviors, which can be attributed to the significant reduction of the cations diffusion barrier within the lattice, i.e., from 1.5 to 0.4eV. As a result, the capacities of anatase TiO2 with 2.4% lattice expansion are ≈100 times higher than the routine one in natural seawater, and ≈200 times higher in aqueous Na+ electrolyte. The finding will significantly advance aqueous seawater energy storage devices closer to practical applications.

Ultra‐Low Power and Reliable Dynamic Memtransistor Based on Charge Storage Junction FET with Step‐Wise Potential Barrier for Energy‐Efficient Edge Computing Framework

AbstractThe emergence of technologies such as Artificial Intelligence (AI) and the Internet of Things (IoT) has ushered in the era of big data. The demand for low‐power hardware systems and efficient algorithms has become more imperative. In this study, an ultra‐low‐power dynamic memtransistor based on the charge storage junction Field‐Effect Transistor (FET) with a step‐wise potential barrier is developed. A simple yet efficient device structure allows for analog programming and spontaneous relaxation. The device demonstrated fast speed (tens of nanoseconds (ns)) and low current (in picoamperes (pA)), resulting in ultra‐low programming power (in attojoules (aJ)). Furthermore, the device exhibited high reliability, with a 0.4% cycle‐to‐cycle variation and endurance over 107 pulses, owing to its non‐structural destructive operation process. An operation scheme is developed that enables read on/off and program/inhibition mode for 2T (1 memtransistor‐1 selecting transistor) array. The capability to distinguish temporal data using the device's spontaneous relaxation characteristics is demonstrated. A reservoir computing (RC) system framework is constructed using simulation and verified that the dynamic memtransistor can extract features efficiently from a hand‐written digit dataset. It is anticipated that the developed dynamic memtransistor, with its distinctive temporal characteristics, will play a pivotal role in developing a novel low‐power computing framework.

A Review on the Recent Advances in Battery Development and Energy Storage Technologies

Energy storage is a more sustainable choice to meet net-zero carbon foot print and decarbonization of the environment in the pursuit of an energy independent future, green energy transition, and uptake. The journey to reduced greenhouse gas emissions, increased grid stability and reliability, and improved green energy access and security are the result of innovation in energy storage systems. Renewable energy sources are fundamentally intermittent, which means they rely on the availability of natural resources like the sun and wind rather than continuously producing energy. Due to its ability to address the inherent intermittency of renewable energy sources, manage peak demand, enhance grid stability and reliability, and make it possible to integrate small-scale renewable energy systems into the grid, energy storage is essential for the continued development of renewable energy sources and the decentralization of energy generation. Accordingly, the development of an effective energy storage system has been prompted by the demand for unlimited supply of energy, primarily through harnessing of solar, chemical, and mechanical energy. Nonetheless, in order to achieve green energy transition and mitigate climate risks resulting from the use of fossil-based fuels, robust energy storage systems are necessary. Herein, the need for better, more effective energy storage devices such as batteries, supercapacitors, and bio-batteries is critically reviewed. Due to their low maintenance needs, supercapacitors are the devices of choice for energy storage in renewable energy producing facilities, most notably in harnessing wind energy. Moreover, supercapacitors possess robust charging and discharging cycles, high power density, low maintenance requirements, extended lifespan, and are environmentally friendly. On the other hand, combining aluminum with nonaqueous charge storage materials such as conductive polymers to make use of each material’s unique capabilities could be crucial for continued development of robust storage batteries. In general, energy density is a key component in battery development, and scientists are constantly developing new methods and technologies to make existing batteries more energy proficient and safe. This will make it possible to design energy storage devices that are more powerful and lighter for a range of applications. When there is an imbalance between supply and demand, energy storage systems (ESS) offer a way of increasing the effectiveness of electrical systems. They also play a central role in enhancing the reliability and excellence of electrical networks that can also be deployed in off-grid localities.

Synthesis of Ni3V2O8-rGO composite nanostructure for high-performance hybrid supercapacitors via hydrothermal method

To address global energy demand, major efforts have been made to develop cutting-edge electrode materials for electrochemical energy storage (EES) devices. The present article discusses the hydrothermal synthesis of bare nickel vanadate and a nickel vanadate/reduced graphene oxide (Ni3V2O8-rGO) composite for supercapacitor applications. The physicochemical properties of pure Ni3V2O8 (NVO) and the Ni3V2O8-rGO (NVO-rGO) composite were investigated using a variety of characterization tools. The electrochemical traits of the NVO-rGO composite outperform bare NVO due to the synergistic effect. At a current density of 1 mAcm−2, the NVO and NVO-rGO nanostructures exhibit excellent specific capacitances of 85 Fg−1 and 108 Fg−1, respectively. These nanostructures also have energy densities of about 3.82 and 5.02 WhKg−1, with power densities of 141.75 and 151.57 WKg−1 for NVO and NVO-rGO composite, respectively. Electrochemical impedance spectroscopy (EIS) studies revealed a charge resistance of 2.05 Ω. The transfer coefficient and standard rate constant indicate that the charge storage mechanism is based on a quasi-reversible redox process. The present investigation demonstrates that the NVO-rGO composite has exceptional electrochemical performance. The outstanding electrochemical performance of both NVO and NVO-rGO underlines their potential as novel and promising materials for supercapacitor applications, implying significant feasibility for large-scale utilization.