Anode Material For Supercapacitors Research Articles

Microwave-assisted synthesis of CuxTey as an anode material for supercapacitors

Microwave-assisted synthesis of CuxTey as an anode material for supercapacitors

Endogenous Interfacial Mo-C/N-Mo-S Bonding Regulates the Active Mo Sites for Maximized Li+ Storage Areal Capacity.

Active sites, mass loading, and Li-ion diffusion coefficient are the benchmarks for boosting the areal capacity and storage capability of electrode materials for lithium-ion batteries. However, simultaneously modulating these criteria to achieve high areal capacity in LIBs remains challenging. Herein, MoS2 is considered as a suitable electroactive host material for reversible Li-ion storage and establish an endogenous multi-heterojunction strategy with interfacial Mo-C/N-Mo-S coordination bonding that enables the concurrent regulation of these benchmarks. This strategy involves architecting 3D integrated conductive nanostructured frameworks composed of Mo2 C-MoN@MoS2 on carbon cloth (denoted as C/MMMS) and refining the sluggish kinetics in the MoS2 -based anodes. Benefiting from the rich hetero-interface active sites, optimized Li adsorption energy, and low diffusion barrier, C/MMMS reaches a mass loading of 12.11mgcm-2 and showcases high areal capacity and remarkable rate capability of 9.6mAhcm-2 @0.4mAcm-2 and 2.7mAhcm-2 @6.0mA cm-2 , respectively, alongside excellent stability after 500 electrochemical cycles. Moreover, this work not only affirms the outstanding performance of the optimized C/MMMS as an anode material for supercapacitors, underscoring its bifunctionality but also offers valuable insight into developing endogenous transition metal compound electrodes with high mass loading for the next-generation high areal capacity energy storage devices.

Secondary High-Temperature Treatment of Porous Carbons for High-Performance Supercapacitors

Supercapacitors are extensively used in urban rail transit, electric vehicles, renewable energy storage, electronic products, and the military industry due to its long cycle life and high power density. Porous carbon materials are regarded as promising anode materials for supercapacitors due to their high specific surface areas and well-developed pore structures. However, the over-developed pore structure often results in poor conductivity and reduced cycle stability due to the destruction of a carbon skeleton. Herein, we introduce an advanced strategy for preparing porous carbon with high specific surface areas (3333 m2 g−1), high electrical conductivity (68.6 S m−1), and fast ion transport channels through secondary high-temperature carbonization treatment. As a result, the fabricated porous carbon anode delivers a high specific capacitance (199.2 F g−1 at 1 A g−1) and outstanding rate performance (136.3 F g−1 at 20 A g−1) in organic electrolyte. Furthermore, the assembled symmetrical supercapacitor achieves an energy density of 43.2 Wh kg−1 at 625.0 W kg−1, highlighting the potential of a secondary high-temperature carbonization strategy in practical applications.

Mo-doped NiCo-LDH nanoflower derived from ZIF-67 nanosheet arrays for high-performance supercapacitors

Layered double hydroxides (LDHs) have gained utmost concern as anode materials for supercapacitors considering their high theoretical specific capacitances, short ion channels and good electrochemical properties. However, their practical application is hindered by low conductivity and limited performance in terms of charge storage. In this study, the researcher successfully synthesized Mo-doped NiCo-LDH nanoflower structures through a straightforward hydrothermal reaction and calcination utilizing lamellar ZIF-67 as a precursor. By adjusting the Mo doping concentration, the researcher was able to maintain the unique multilevel nanoflower-like structure of NiCo-LDH. Furthermore, the inclusion of Mo as a dopant introduced an amorphous phase and effectively modulated the electronic structure of NiCo-LDH, resulting in accelerating charge storage kinetics and reduced volume change. The 0.075 Mo-doped NiCo-LDH exhibited a specific capacitance of 1368.4C g−1 at 1 A g−1, with the capacity retention of 88.4 % at 10 A g−1. Additionally, the assembled asymmetric supercapacitor constructed with 0.075 Mo-doped NiCo-LDH@C//RGO achieved an energy density of 52.2 Wh kg−1 with a power density of 799.3 W kg−1. This study provides valuable insights into the rational doping of Mo elements for the controlled synthesis of supercapacitor electrode materials.

Role of Heteroatoms (N, P, O, and S) in Co3O4-Doped Carbons Derived from ZIF-67-Polyphosphazene Nanohybrids as Anode Materials for Supercapacitors

Role of Heteroatoms (N, P, O, and S) in Co₃O₄-Doped Carbons Derived from ZIF-67-Polyphosphazene Nanohybrids as Anode Materials for Supercapacitors

Suppresses Dissolution and Enhanced Conductivity in Core–Shell VO2@Ni3N as a High‐Capacitance and Improved Cycling Anode Materials for Supercapacitor

Vanadium dioxide, as one of superior pseudocapacitive electrode candidates in supercapacitors, suffers from the detrimental dissolution in aqueous electrolytes and poor intrinsic electronic conductivity. Herein, an ultrathin Ni3N shell is deposited on the VO2 surfaces (VO2@Ni3N) to inhibit the inevitable dissolution during charge/discharge processes. Meanwhile, the Ni3N coating layer also provides sufficient electron transport pathways for the rapid surface faradic reactions of VO2, promoting the electrochemical reaction kinetics. The designed VO2@Ni3N anode exhibits significant energy storage ability, especially at large current density (2058 F g−1 at 1 A g−1, 711 F g−1 at 7 A g−1), and the considerable cycling lifespans (capacitance retention of 91.3% after 5000 cycles). The asymmetric supercapacitor presents an energy density of 41.73 Wh kg−1 at a power density of 1176.7 W kg−1. This study may enlighten the design of advanced pseudocapacitive materials for practical electrochemical energy storage technologies.

Moringa oleifera and its spent tea waste composites as sustainable anode candidates for energy storage applications: Morphological and electrochemical performance studies

Activated carbons of husk of Moringa bark (Mo) and its spent tea waste composites (Stw) (Mo-T1 —T4) are synthesized, characterized for structure and morphology, and investigated for their anode candidacy in supercapacitor and OER applications by cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronopotentiometry (galvanostatic charge/discharge; GCD), electrochemical impedance spectroscopy (EIS), and chronoamperometry (controlled potential electrolysis; CPE). Electrochemical studies for supercapacitor application reveal Mo-T1 and then Mo the best anode candidates amongst others. With high specific capacitance of 211.8 Fg-1 (CV@ 10 mVs-1), and 231.4 Fg-1 (GCD@ 0.5Ag-1), greater cyclic stability (93% capacitance retention), greater discharging time (324s @ 0.5Ag-1), and low solution resistance (1.67 Ω), Mo-T1 is not only proving to be the best anode candidate amongst studied materials but also these values were found greater/or comparable with various recently reported biomass derived anode materials for supercapacitor. The same materials (Mo-T1 and Mo) are found to be more efficient anode candidates for OER performance in water splitting with comparatively lower values of onset potential, overpotential, Tafel slopes and greater current stability at constant potential (1.65 V vs. RHE) during electrolysis. Overall findings indicate Mo-T1 and Mo the potential anode candidates for energy storage applications.

Achieving high quantum capacitance graphdiyne through doping and adsorption.

In recent years, a new two-dimensional carbon material, graphdiyne (GDY), has attracted extensive attention in the field of energy storage, due to its unique topological and electronic structures, high charge mobility, and excellent electron transport properties. However, the disappearance of the density of states near the Fermi level leads to a low quantum capacitance (CQ) of pristine GDY, which limits its application in supercapacitors. Here, we propose doping and metal atom adsorption to be efficient ways to increase the CQ of GDY. Based on first-principles density functional theory, the effects of doping B, N, P, and S atoms and adsorbing Au, Ag, Cu, Ti, and Al atoms on the CQ of GDY are systematically investigated. The results show that the CQ of GDY can be significantly improved by introducing doping/adsorption, which could be a potential cathode material and anode material for supercapacitors. Our work provides an effective way for GDY to be applied as an efficient electrode material for supercapacitors.

Phosphate ion-functionalized nickel-cobalt layered double hydroxide nanosheets derived from metal-organic framework compounds for high-performance asymmetric supercapacitors

The modification by functionalized ions (surface modification or doping) presents facile and efficient access to enhance the electrochemical performance of electrode materials. However, the effect of functionalized ions on the structure-performance relationship of electrode materials is not yet apparent. Herein, we develop a novel phosphate ion-functionalized nickel-cobalt layered double hydroxide nanosheet (Ni-Co-P80) derived from metal-organic framework compounds prepared as anode material for supercapacitors. The obtained Ni-Co-P80 not only remains characterized by high specific surface area and porosity, but also possesses more active sites and higher electrical conductivity with phosphate modification, thus improving the charge transfer kinetics. The electrochemical test results show that the highest specific capacitance of Ni-Co-P80 modified with phosphate ions increases by 49.7% compared to pure phase LDH. More impressively, the assembled asymmetric supercapacitor exhibits an excellent energy density of 64.89 Wh kg-1 at a power density of 1600 W kg-1 with an ultralong cyclic performance of 77.78% capacitance retention after 5000 cycles. This study explicitly demonstrates the remarkable enhancement of specific capacitance of layered double hydroxide following modification with phosphate ions. It brings a prospective pathway toward the rational design of LDH-based high-performance asymmetric supercapacitors.

Effect of vacancy defects and co-doping on the quantum capacitance of silicene-based electrode materials

The design of electrode materials with high energy storage properties plays a key role in developing electric double-layer supercapacitor technology. In recent years, silicene has aroused great interest in the field of energy storage. In this paper, the electronic structure and quantum capacitance of single vacancy defects, topological defects and four kinds of double vacancy defects were systematically investigated, based on density functional theory. It is found that silicene with the topological defect is the most stable defect structure, with the formation energy of 2.067 eV. In the systems of Ag, Au, Cu, Ti, Mn and N co-doping on silicene, the structural stability enhances with the increase of N atoms. CuN2-o-Si structure shows the highest quantum capacitance of 145.499 μF/cm2, which could be an ideal anode material for supercapacitors. The increased quantum capacitance is due to the introduction of localized states near the Fermi level. Both defects and doping can enhance the quantum capacitance of silicene-based electrode materials, and then improve the total interfacial capacitance.

Fabrication of CuFe2O4@g-C3N4@GNPs nanocomposites as anode material for supercapacitor applications

The aim of this study was to synthesize CuFe2O4 together with g-C3N4 and GNPs in various combinations on the surface of Ni foam for use as anode materials in supercapacitors. The fabricated electrodes were investigated by XRD, FTIR, XPS, BET, SEM and TEM for content and by CV, GCD and EIS analysis for electrochemistry. The characterization results showed that CuFe2O4 was successfully synthesized together with g-C3N4 and GNPs in a nanosponge-like geometry. The highest value of specific capacitance was found to be 989 mF/cm2 at 2 mA measurement in the triple combination. Moreover, the stability of this electrode was measured to be 70% after 1500 cycles at 16 mA, while the energy and power densities were calculated to be 27.8 mWh/cm2 and 300 mW/cm2, respectively. The EIS results show that the carbon-based component increased the Cs value by decreasing the charge transfer and diffusion resistances of the electrodes. Compared to its counterparts in the literature, its Cs value is quite high, but its stability is low, so it can be used in low-cycle applications.

Co3Se4 quantum dots encapsulated with nitrogen-doped porous nanocarbon as ultrastable electrode material for water-based all-solid asymmetric supercapacitors

Transition metal selenides (TMSe) are considered as potential anode materials for supercapacitors because of their abundant reserves and high safety.However, their poor conductivity limits their high rate performance and stability.In this paper, an N-doped porous nanocarbon-coated Co3Se4 quantum dots (NCCS-QDs) composite is prepared as the cathode material of supercapacitor. The formation of Co3Se4 quantum dots complies with a size minimization strategy to speed up ion transport. At the same time, the Co0.85Se nanosheets are converted into Co3Se4 quantum dots, avoiding the collapse of the nanosheets during the electrochemical process. In addition, the porous nanocarbon coating increases the number of active sites and the contact area between the electrode and the electrolyte, which can provide more ion transport channels and pore sizes, while avoiding the generation of inactive clusters in the electrochemical reaction of quantum dots. The as-assembled NCCS-QDs-2//AC ASCs devices demonstrate excellent electrochemical performance with an energy density of 84.59 Wh kg−1 at a power density of 799.99 W kg−1.At the same time, the ASCs device showed excellent cycle stability, with 95.6% of the initial capacitance still maintained after 15,000 charge and discharge cycles.The excellent electrochemical performance of NCCS-QDs-2//AC ASC device proves that NCCS-QDs composite material has a broad application prospect in the cathode material of supercapacitor.

Pseudocapacitivebehavior of coin-like NiO/r-GO nanocomposites as an efficient electrode material for energy storage application

ABSTRACT Herein, a novel coin like NiO/r-GO nanocomposite was synthesised by the facial hydrothermal method. The prepared materials were used as an anode material for supercapacitors in the aqueous KOH electrolyte solution. The phase purity and crystal structure, morphology, chemical composition, chemical oxidation state of the prepared samples were studied by Powder XRD, FE-SEM with elemental mapping, TEM, and XPS techniques.The FE-SEM and TEM analysis of NiO/r-GO composite possesses a coin-like NiO morphology with covered r-GO nanosheets and an average size of 200 ± 50 nm. The prepared NiO/r-GO nanocomposite electrode material exhibits a high specific capacity of 115Cg−1 at 0.5 Ag−1, which is high rate capability, and stable GCD cycling performance (98% retention after 5000 successive charge-discharge cycles at 10 Ag−1).

Heterostructure‐Regulated Metal Silicates Composite Material for Enhancing the Lithium‐Ion Batteries Performance

AbstractNoticeable surface reaction in the energy storage mechanism has attracted tremendous research due to its relationship with electrochemical capacity and rate capability. In this work, in‐situ grown heterostructured metal silicates are prepared through a facile hydrothermal method. The composites are employed as anodes for supercapacitor and lithium‐ion batteries (LIBs). The ratio of cobalt and copper in the heterostructure has a significant effect on its properties, including porosity, electrical conductivity, and pseudo‐capacitance contribution during the energy storage process. The combination of metal silicates, heterostructure, and porous bio‐mass derived carbon into one system results in a unique electrode material with optimized reaction kinetics. The integration leads to a superior capacity and rate capability. Specifically, the cobalt silicate/copper silicate heterostructure composites present improved electrochemical performance as anode for LIBs and supercapacitor. For lithium‐ion storage, the B‐C@CoCuSi‐(3‐1) delivers a capacity of 574.5 mAh g−1. When used as an anode material for supercapacitor, the B‐C@CoCuSi‐(1‐3) shows a capacitance of 80.4 F g−1.

Facile hydrothermal synthesis of cobaltosic sulfide nanorods for high performance supercapacitors

With high reactivity, electrical conductivity, theoretical specific capacitance and well redox reversibility, transition metal sulfides are considered as a promising anode material for supercapacitors. Hence, we designed a simple two-step hydrothermal process to grow Co4S3 nanorod arrays in situ on flexible carbon cloth substrates. Benefited from the larger specific surface area of nanoarrays, the binder-free Co4S3 electrode demonstrates a higher specific capacity of 1.97 F cm−2 at a current density of 2 mA cm−2, while the Co3O4 electrode has a capacity of only 0.07 F cm−2 at the same current density. Surprisingly, at a high scan rate of 200 mV s−1, the synthesized Co4S3 electrode still maintains almost 100% of its initial capacitance after 5000 cycles. Moreover, when using the prepared Co4S3 and MnO2 electrode as the anode and cathode, the fabricated flexible supercapacitor obtains a high volumetric energy density of 0.87 mW h cm−3 (power density of 0.78 W cm−3) and a peak power density of 0.89 W cm−3 (energy density of 0.50 mW h cm−3). The excellent electrochemical properties imply that there is a large market for the prepared materials in flexible energy storage devices.

TEA driven C, N co-doped superfine Fe3O4 nanoparticles for efficient trifunctional electrode materials

Poor conductivity is an obstacle that restricts the development of the electrochemistry performance of Fe3O4. In this work, a novel carbon and nitrogen co-doped ultrafine Fe3O4 nanoparticles (CN-Fe3O4) have been synthesized by triethylamine (TEA) induction and subsequent calcination. The addition of TEA could not only regulate the size of Fe3O4 nanoparticles, but also promote the formation of amorphous carbon layer. Well-designed CN-Fe3O4 heterostructures provide a highly interconnected porous conductive network, large heterogeneous interface area, large specific surface area and a large number of active sites, which greatly improve conductivity and promote electron transfer and electrolyte diffusion. The prepared CN-Fe3O4 electrode exhibits a high specific capacitance of 399.3 mF cm−2 and good cycling stability. Meanwhile, CN-Fe3O4 catalyst exhibits excellent oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) activities, with overpotentials of 136 and 281 mV at the current density of 10 mA cm−2, respectively. This work provides a promising approach for the design of high-performance anode materials for supercapacitors and provides profound implications for the development of catalysts with bifunctional catalytic activity.

Oxygen-vacancy abundant alpha bismuth oxide with enhanced cycle stability for high-energy hybrid supercapacitor electrodes

Bi2O3 is an outstanding electrode material due to its high theoretical specific capacity. Hence, the synthesis of δ-Bi2O3 materials with high oxygen-vacancy contents could improve their electrochemical performances but causes easy conversion to α-Bi2O3 with low oxygen-vacancy contents, leading to poor cycling stability and limited practical applications. To overcome these problems, an effective strategy for constructing high oxygen vacancies α-Bi2O3 on activated carbon fiber paper (ACFP) is developed in this study. To this end, ACFP/Bi(OH)3 is first synthesized by the solvothermal method and then converted to ACFP/α-Bi2O3 by in situ electrochemical activation. The proposed innovative electrochemical method quickly and easily introduces oxygen vacancies while preserving the three-dimensional structure, thereby promoting the charge transfer and ions diffusion in ACFP/α-Bi2O3. Consequently, the specific capacity of ACFP/α-Bi2O3 reaches 906C g−1 at 1 A g−1, and the capacity retention remains above 70% after 3000 cycles, a value higher than that of δ-Bi2O3 (45%). Furthermore, the hybrid supercapacitor device assembled by ACFP/α-Bi2O3 delivers a maximum energy density of 114.9 Wh kg−1 at 900 W kg−1 and outstanding cycle stability with 73.56 % retention after 5500 cycles. In sum, the proposed ACFP/α-Bi2O3 with high performance and good stability looks promising for use as bismuth-based anode materials in supercapacitors and aqueous batteries.

MoO3@ZnO Nanocomposite as an Efficient Anode Material for Supercapacitors: A Cost Effective Synthesis Approach

MoO₃@ZnO Nanocomposite as an Efficient Anode Material for Supercapacitors: A Cost Effective Synthesis Approach

Amalgamation and characterization of graphene-calcium titanate composite for electrochemical studies

Graphene is a proficient anode material for super capacitors. A few reasons can be credited to the current enthusiasm for graphene as a special morphology carbon material with potential for electrochemical vitality stockpiling applications. Graphene has predominant electrical conductivity than graphite and different allotropes of carbon due to its high surface region and substance resilience. In this work, Graphene Oxide was blended by adjusted Hummer's strategy and it was decreased to graphene utilizing hydrazine hydrate. Graphene-Calcium titanate composites were set up by arrangement blending technique. Moreover, its morphology and properties were portrayed by X-beam diffraction (XRD), filtering electron magnifying instrument (SEM), Fourier change infrared spectroscopy (FT-IR), and electro-synthetic estimations. The as-arranged nano composites were tried for its super capacitance property by cyclic voltammetric (CV) explore in 2 M KOH electrolyte. CV was performed at an expected scope of 0.6 to – 0.6 V at 100 mV/s examine rate, and results show a great capacitive conduct of the nano composites.

Ingeniously designing anode material of Ni3S2/MnS2@Carbon nanocomposite with a wide potential window of 1.3 V

Nano-structured composite materials of Ni3S2/MnS2 at carbon are synthesized by a one-step carbonization and vulcanization. The morphology of the composites is controlled by adjusting the ratio of aniline and ammonium persulfate (both as an initiator and a sulfur source). The nanocomposite material has a porous structure stacked by sheets, which can expose more active sites; in the meantime, the porous structure is conducive to the rapid transfer of electrolyte ions. Furthermore, the synthesized nanocomposite material can be used as anode materials for supercapacitor, which has a wide potential window from -1.1 to 0.2 V and shows high specific capacitance of 291 F g−1 at 0.5 A g−1 in 6 M KOH. The asymmetric supercapacitors further assembled with Ni(OH)2 as cathode materials has a specific capacitance of 67 F g−1 at 0.5 A g−1 and good cyclic stability (capacitance retention of 74.5% over 2000 cycles). The electrochemical properties of asymmetric supercapacitors deliver a maximum energy density of 18.8 Wh kg−1 at power density of 360.8 W kg−1. It indicates that this kind of nanocomposite material is a very promising negative material for supercapacitors with excellent electrochemical performance.