Hybrid Supercapacitor Device Research Articles

Enhanced electrochemical activity by NiCo-P nano-particles modified Co-MOF nanorods

The design and preparation of high-performance electrode materials are among the most extensively researched topics in supercapacitor studies. By combining the three-dimensional structure and compatibility of cobalt-based metal-organic framework (Co-MOF) with the high redox activity of metal phosphates, a green, efficient, and safe co-precipitation and electro-deposition strategy was employed to fabricate the Co-MOF@NiCo-P heterostructure composite electrode material, with NiCo-P nanoparticles uniformly decorated on the surface of Co-MOF, addressing the issues of limited conductivity of Co-MOF and the tendency of NiCo-P to aggregate when grown in situ on foam nickel. In a three-electrode system, the Co-MOF@NiCo-P electrode exhibits specific capacities of 1389.8 F g−1 at 1 A g−1 and 964.3 F g−1 at 20 A g−1. The assembled Co-MOF@NiCo-P//AC hybrid supercapacitor device demonstrates energy densities of 54.08 Wh kg−1 (22.92 Wh kg−1) and power densities of 825 W kg−1 (8250 W kg−1), showing promising application prospects. This research offers a novel method for developing high-performance electrode materials.

Ternary g-C3N4/Co3O4/CeO2 nanostructured composites for electrochemical energy storage supercapacitors

Extensive use of fossil fuels causes heavy discharge of carbon dioxide, depleting energy resources and this requires environmentally friendly and effective energy storage materials. Hybrid supercapacitors (HSCs) are recently developed as effective energy storage materials enabling high capacitance retention rate and quick charging. Herein, synthesis of two-dimensional g-C3N4 nanosheets supported onto three-dimensional flower-like Co3O4/CeO2 (CoCe) ternary synergistic heterostructures are developed as effective electrodes for hybrid supercapacitor applications. Addition of g-C3N4 produces substantial surface active sites, enabling its synergistic effect with CoCe to enhance electrochemical performance having exceptional conductivity. The CoCe/g-C3N4 ternary composite electrode exhibits a higher specific capacitance of 1088.3 F g−1 at 1 A g-1 with 96 % of recycling stability over 5000 cycles, which is ∼5.5 and ∼5 folds higher specific capacitance than the pristine g-C3N4 and CoCe electrodes. EIS analysis revealed that CoCe/g-C3N4 electrode offered reduced charge transfer resistance compared to pristine electrodes. The fabricated two-electrode HSC device displays outstanding retention after 10,000 cycles with an ultra-high specific capacitance of 119.8 F g−1, excellent energy density 37.4 Wh kg−1 and power density of 749.9 W kg−1. This research showcases the perspectives of CoCe/g-C3N4 ternary electrodes in hybrid supercapacitors and other renewable energy storage devices.

Ag-decorated ZnCo2S4/SiO2 nanocomposite as a high-performance supercapacitor electrode

Ag-decorated ZnCo2S4/SiO2 nanocomposite was utilized in this study as a potential supercapacitor electrode. Ag nanoparticles demonstrate a low level of pseudo-capacitance and their capacity to improve charge transfer. The specific capacitances of the ZnCo2S4, ZnCo2S4/SiO2, and Ag@ZnCo2S4/SiO2 electrodes were 935, 1066, and 1623 Fg−1, respectively, at 1 Ag−1 current density. The Ag@ZnCo2S4/SiO2 electrode exhibits remarkable cycle stability (100 % coulombic efficiency and capacitance retention of approximately 91.7 % at 10 A g−1 after 10,000 cycles). Furthermore, the symmetric supercapacitor (Ag@ZnCo2S4/SiO2//Ag@ZnCo2S4/SiO2) possesses a broad potential window of 1.5 V, a maximal energy density of 68.6 Whkg−1, and a specific power of 23.88 kWkg−1. Furthermore, the hybrid supercapacitor device (Ag@ZnCo2S4/SiO2//Ag@ZnCo2S4/SiO2) demonstrated a coulombic efficiency of 100 % and a capacitance retention of 92.3 %. Consequently, the Ag@ZnCo2S4/SiO2 composite electrode was suitable for high-energy supercapacitors due to their high capacitance, remarkable cycle stability, and high energy density.

High performance NiCoSe2@NiFe-MOF@AC Nanocomposite electrode for energy storage and precise detection of mono-sodium glutamate

Hybrid supercapacitors, a fascinating appliances that combines the best of both batteries and supercapacitors, showcase remarkable improvements in power and energy densities. Here, a two-step technique was used to synthesis NiCoSe2@NiFe-MOF. In first step NiCoS was synthesis using electrodeposition approach and in second step the NiCoSe2@NiFe-MOF was synthesis using vacuum-assisted filtering. The specific capacitance of the NiCoSe2@NiFe-MOF composite used as the supercapacitor electrode in a three-electrode system was (2882.5 F g−1) and specific capacity is 1729.8 C g−1, much greater than that of the NiCoSe2 electrode material which was 967.4 C g−1 at current density of 1.5 Ag−1, In addition, a hybrid supercapacitor device (NiCoSe2@NiFe-MOF//AC) has been developed and successfully demonstrates a specific capacity of 205.45 C g−1 at 0.5 A g−1. The energy density is measured in units of WhKg−1 with a numeric values of 78.3, while at 2.9 KWKg−1 the power density is recorded. This device has been tested for up to five thousands cycles of discharging (87.8%) and charging (94.2%), achieving an impressive capacity retention rate of 96.8%.Additionally, an amperometric immunosensor was fabricated by employing the NiCoSe2@NiFe-MOF nanocomposite to detect Mono-Sodium Glutamate (MSG). A constant linear association was observed between the concentration of MSG and the variation in current, encompassing the entire detection range of 0.05–200 μM. The findings of our study offer an exciting starting point for the development of energy storage systems with greater capacity.

Nickel aluminum selenide wrapped by NiCoAl-layered double hydroxide enables a robust structure for supercapacitors

To explore a simple and convenient strategy for the construction of hybrid composites as advanced electrode materials for supercapacitors (SCs), this research realized the construction of nickel − aluminium selenide (NiAlSe)@NiCoAl-layered double hydroxide (NiCoAl-LDH) heterostructure. In-situ hybridization of NiCoAl-LDH nanosheets onto NiAlSe nanoparticles anchored on carbon cloth generates a special core–shell heterostructure, which enhances the exposure of active centers and increases the surface area. The formation of heterogeneous interfaces between NiAlSe and NiCoAl-LDH alters the electronic architecture and accelerates the electron/ion migration. By making full use of the structural benefits and the cooperative effect, the NiAlSe@NiCoAl-LDH composite electrode delivered a large capacitance (Cs) of 1789.2F/g at 1 A/g along with a high retention rate of 94.7 % over 5,000 cycles, which outperforms the bare NiAlSe and NiCoAl-LDH. Meanwhile, the assembled NiAlSe@NiCoAl-LDH hybrid supercapacitor (HSC) attained maximum specific energy (Es) of 71.5 Wh kg−1. This HSC device exhibits superior cyclic durability of 92.1 % after 30,000 cycles. Thereby, this research offers valuable insights into the construction of robust electrode materials for advanced HSC devices.

Electrodeposited Co0.85Se/Ni3Se2 heterostructure as an efficient binder-free cathode for fast electrochemical energy storage devices

In this study, a facile technique was developed to generate a bimetallic Co0.85Se/Ni3Se2 heterostructure through a straightforward one-step electrodeposition process. The resulting structure proved to be an efficient cathode for fast charge/discharge electrochemical energy storage devices. The composition and morphology of the cathode can be easily adjusted by varying the molar ratio of Co/Ni precursors. The optimized Co0.85Se/Ni3Se2 (3:1) electrode demonstrated an impressive specific capacity of 141.9 mAh g−1 at a current density of 1 A g−1. It retained a capacity of 103.5 mAh g−1 at a high current density of 8 A g−1 due to its heterostructure nature. The assembled hybrid supercapacitor (HSC) device based on this optimized cathode achieved remarkable energy and power densities. Additionally, the Co0.85Se/Ni3Se2 (3:1) electrode was successfully demonstrated in micro-HSC (μ-HSC) applications, exhibiting favorable cycling stability during 480-h floating tests. These findings suggest that the synthesized Co0.85Se/Ni3Se2 cathode has great potential for use in high-performance electrochemical energy storage devices.

Insights of oxygen vacancies engineered structural, morphological, and electrochemical attributes of Cr-doped Co3O4 nanoparticles as redox active battery-type electrodes for hybrid supercapacitors

The global warming issue is spurring the development of renewable energy solutions, where supercapacitors are emerging as promising options for energy storage. Despite advancements in battery-type materials, doping is a practical approach to enhancing electrochemical performance. In this study, using the solution combustion method, we synthesized spinel Co3O4 nanoparticles doped with chromium (Cr) at 2.5 % and 5 % concentrations. The addition of Cr significantly modifies the structural, morphological, surface, and electrochemical properties of Co3O4 nanoparticles. Raman and X-ray photoelectron spectroscopy confirm that this doping method effectively regulates the oxygen vacancy defect level. Moreover, Cr dopants and oxygen vacancies modify electronic states, facilitating more accessible contact to active sites, improving electrical conductivity and more intricate redox chemistry. Notably, the 2.5 % Cr-doped Co3O4 configuration demonstrates substantially enhanced specific capacity (334.64 C g−1/92.95 mAh g−1 at 1 A g−1) and rate performance (59 %), surpassing those of 5 % Cr-doped Co3O4 and undoped Co3O4. Furthermore, the as-fabricated 2.5 % Cr-doped Co3O4//activated carbon (AC) hybrid supercapacitor (HSC) device exhibits a noteworthy energy density of 42.5 Wh kg−1 at 1295.73 W kg−1, withstanding 33.54 Wh kg−1 even at a power density of 5720.46 W kg−1. The HSC device showcases outstanding cyclic performance with 100 % capacity retention after 5000 cycles. Therefore, our work offers a viable way to improve the efficiency of hybrid supercapacitors by providing essential insights into the design of defect-engineered battery-type electrode materials.

Impact of Nitrogen-Enriched 1T/2H-MoS2/CdS as an Electrode Material for Hybrid Supercapacitor.

Transition metal chalcogenides (TMX) have attracted energy researchers due to their role as high-performance electrode materials for energy storage devices. A facile one-pot hydrothermal technique was adopted to synthesize a molybdenum disulfide/cadmium sulfide (MoS2/CdS) (MCS) composite. The as-prepared samples were subjected to characterization techniques such as XRD, FT-IR, SEM, TEM, and XPS to assess their structure, morphology, and oxidation states. The MoS2/CdS (MCS) composites were prepared in three different ratios of molybdenum and cadmium metals. Among them, the MCS 1:2 (Mo:Cd) ratio showed better electrochemical performance with a high specific capacitance of 1336 F g-1 (high specific capacity of 185.83 mAh g-1) at a specific current of 1 A g-1 for half-cell studies. Later, a hybrid supercapacitor (HSC) device was fabricated with N-doped graphene (NG) as an anode and MCS (1:2) as a cathode, delivering a high specific energy of 34 Wh kg-1 and a specific power of 7500 W kg-1. The high nitrogen content in the MoS2 structure in MCS composites alters the device's performance, where CdS supports the composite structure through its conductivity and encourages the easy accessibility of ions. The device withstands up to 10 000 cycles with a higher Coulombic efficiency of 97% and a capacitance retention of 90.25%. The high-performance NG//MCS (1:2) HSC may be a potential candidate alternative to the existing conventional material.

Achieving Complete Conversion from Nickel Foam to Nickel Sulfide Foam for a Freestanding Hybrid‐Supercapacitor Electrode

AbstractWe present a unique, one‐step, hydrothermal process to prepare nickel sulfide (Ni3S2) foam by a simple and direct conversion from nickel foam, which contributes both as a scaffold for the reaction and as reactant. The Ni3S2 foam exhibits remarkable mechanical stability, retaining the structural integrity of the foam and excellent crystallinity even after ultrasonication at 200 W for 30 mins. We document the transformation of the nickel foam template into a Ni3S2 foam, highlighting the role of synthesis duration on the phase evolution and unique morphology of Ni3S2. PXRD and SEM analyses reveal a complete transformation after 24 hours from the nickel foam to a pure Ni3S2 foam, which has a highly porous and interconnected ultra‐thin nanosheet architecture. This significantly enhances the surface area and provides many electrochemical reaction sites. In a three‐electrode cell, the capacity of the Ni3S2 foam electrode is 3.9 C cm−2 at 8 mA cm−2, which is higher than previous reports for Ni3S2. In a hybrid supercapacitor device, the Ni3S2 foam demonstrates significant increase in capacitance through 500 cycles and the capacitance plateaus after 2000 cycles. Even after 8500 continued charge‐discharge cycles, the device exhibits excellent cycle stability indicating improvement with age.

Facile synthesis of silver nanoparticles using Calotropis procera leaves: unraveling biological and electrochemical potentials

The alarming rise of pathogen antibiotic resistance presents a major global health challenge and demands a novel way to control the microbial infections. Simultaneously, nanotechnology has found numerous uses in electrical as well as electronic systems, including timing, filtering, power factor adaptation, and capacitors for energy storage. This work investigates the synthesis and characterization of a silver nanoparticle (AgNPs) utilizing Calotropis procera (CPL) leaf extract. The optimization of synthesis process and the reduction of nanoparticles (NPs) were validated by UV–visible spectroscopy. AgNPs' was exhaustively characterized for morphology, crystallinity, zeta-potential, and structural properties. The produced NPs demonstrated a wide range of characteristics, such as antioxidant, antidiabetic, antibacterial, and antifungal effects. Furthermore, remarkable electrochemical performance was indicated by the CPL-AgNPs electrode, which has mesoporous, clustered sphere-shaped particles onto a flexible stainless-steel substrate. This highlights the electrode's potential in energy storage applications. Copper monosulfide served as the anode and CPL-AgNPs as the cathode electrode in tested hybrid supercapacitor devices, which proved remarkable specific capacitances, high specific energy, and exceptionally high specific power. In order to address the twin challenges of antimicrobial resistance alongside advanced energy storage, this study provides a novel and thorough analysis of the basic electrochemistry as well biological properties of AgNPs, clarifying their potential storage of charges mechanisms and biomedical applications.Graphical abstract

Sulfur and nitrogen co-doped Ni/Co carbide 3D polyhedron nanoparticles with hollow core for hybrid supercapacitors

The methodologies for the synthesis of core-shell multilayered morphologies are being intensely explored. Following such scenarios, we report the fabrication of sulfur (S) and nitrogen (N) co-doped nickel/cobalt carbide (S,N@Ni/Co–C) hollow (carbon matrix) polyhedral nanoparticles (PNPs) by facile solvothermal and sulfurization process. The main objective of this research is to study the anomaly behind the structural deformation of the PNPs during the annealing and to propose a relevant method to preserve them by enhancing their abilities. Additionally, the electrochemical properties of the S, N@Ni/Co–C/nickel foam (NF) electrode are optimized and examined, exhibiting a high areal capacity of 563.3 μAh cm−2 and a notable cycling retention of 96 % at 7 mA cm−2 for 5000 cycles in a three-electrode system. Furthermore, the optimized electrode is employed as a positive electrode along with an activated carbon-coated NF as a negative electrode to fabricate a hybrid supercapacitor device which delivers a maximum energy density of 118.9 μAh cm−2 and a maximum power density of 7000 μA cm−2. Finally, it is used as a power source to drive a few real-time electronic devices, especially safety E-bands.

Microwave-assisted synthesis of perovskite hydroxide-derived Co3O4/SnO2/reduced graphene oxide nanocomposites for advanced hybrid supercapacitor devices

The current article reports a facile, ultrafast, and cost-effective, solid-state microwave (MW) synthetic route for the conversion of perovskite hydroxide (CoSn(OH)6) to crystalline metal oxides (Co3O4 and SnO2) with the help of reduced graphene oxide (rGO) nanosheets. In a domestic MW oven, the Co3O4/SnO2/rGO (CSO-rGO) nanocomposite was synthesized within a quick reaction time of only 30 s. The study deeply focused on analyzing the surface morphology, metal oxide attachment on the surfaces of rGO nanosheets, the specific surface area, and the electrochemical performance of supercapacitor devices from the CSO-rGO nanocomposite. As a positive electrode for supercapacitors, the synthesized hybrid electrode displayed a good capacity (146.4C/g) and enhanced cycling stability (103.2 % after 15,000 cycles). Moreover, the corresponding aqueous hybrid supercapacitor device with MW-synthesized rGO as a negative electrode displayed a maximum energy density of 27 Wh/kg and promising cycling stability of 102.4 % after 10,000 cycles. As a whole, compared to the common time-consuming synthetic approaches, the MW-assisted synthetic approach is highly beneficial in terms of short reaction time, cost-effectiveness, and straightforwardness. The MW synthesis methodology employed in this study can be utilized for analogous composite electrodes that incorporate other layered conductive architectures in addition to metal oxides.

Evolution of CuO bundles of nanowires by room temperature surface oxidation of electroplated Cu for high-performing energy storage device

In the present work, copper oxide bundles of nanowires (CuO BNWs) were synthesized by room-temperature surface oxidation of an electroplated Cu layer in an alkaline bath. The time-dependent morphological evolution of CuO BNWs is systematically achieved by varying surface oxidation times. The CuO BNWs provide a high surface area (19.12 m2/g) and have shown excellent supercapacitive performance with a specific capacitance of 509 F/g at 1 A/g current density owing to fast electron transfer paths offered by BNWs. The all-solid-state hybrid supercapacitor device (SS//Cu//CuO-BNWs//KOH-PVA//rGO) demonstrates a specific capacitance of 77.3 F/g and energy density of 22.57 Wh/kg at a power density of 1.29 kW/kg.

Fabrication and characterization of Sb2O3–MoS2 nanocomposites for high performance supercapacitor applications

Binary nanocomposite-based electrodes have been studied extensively in recent times owing to their multiple oxidation states, excellent physico-chemical features, and combined morphology, which are suitable for increasing the electrochemical performance of supercapacitors. The present work deals with Sb2O3–MoS2 nanocomposites electrode for supercapacitor applications. The x-ray diffraction (XRD), Raman, scanning electron microscope (SEM), energy dispersive x-ray (EDX), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) and x-ray photoelectron spectroscopy (XPS) characterizations have been studied to analyze the phase formation, vibrational modes, morphology, elemental composition and binding energies of the prepared Sb2O3–MoS2 nanocomposites electrode material, as well as their electrochemical measurements such as cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) have been analyzed. The developed Sb2O3–MoS2 nanocomposites electrode provides a high specific capacitance of 454.3 F g−1 at the current density of 1 A g−1. Further, the hybrid supercapacitor device has been constructed which shows 104.04 F g−1 of specific capacitance at 2 A g−1 and manifests a good energy density of 24.42 Wh kg−1 at a power density of 1299.89 W kg−1. Additionally, the hybrid device Sb2O3–MoS2//AC exhibits a good capacitive retention of 90.6% and a coulombic efficiency of 100.45% at 10 A g-1 over 8000 cycles.

Ni2P nanosheet-coated N-doped carbon hollow tubes for high-performance hybrid supercapacitors

Ni2P shows significant potential for energy storage devices due to its high capacitance and long-term cyclic stability. However, its poor electrical conductivity and porosity limit its effectiveness in electrode battery-type (BT) applications for hybrid supercapacitors (HSCs). In this study, the Ni2P nanosheet-coated N-doped carbon hollow tubes (Ni2P/NCHTs) derived from polypyrrole (PPy) have been developed. These Ni2P/NCHTs form a unique one-dimension (1D) core-shell structure through a synergetic carbonization and phosphorization process. The resulting Ni2P/NCHTs exhibit a remarkable specific capacitance of up to 150.83 mAh·g−1 (1086 F g−1) at 1 A g−1 in an aqueous electrolyte (2 M KOH) using a three-electrode system. In an HSC device, with Ni2P/NCHTs as the positive electrode and an active carbon fiber (ACF) as the negative electrode, an energy density of 46.53 W h kg−1 is achieved at a power density of 1125 W kg−1 with high cycle stability (99.45 % retention after 5000 cycles). Therefore, Ni2P/NCHTs present a promising candidate for energy storage devices.

Hydrothermal Synthesis of β-NiS Nanoparticles and Their Applications in High-Performance Hybrid Supercapacitors.

In this work, β-NiS nanoparticles (NPs) were efficiently prepared by a straightforward hydrothermal process. The difference in morphology between these NiS NPs was produced by adding different amounts of thiourea, and the corresponding products were denoted as NiS-15 and NiS-5. Through electrochemical tests, the specific capacity (Cs) of NiS-15 was determined to be 638.34 C g-1 at 1 A g-1, compared to 558.17 C g-1 for NiS-5. To explore the practical application potential of such β-NiS NPs in supercapacitors, a hybrid supercapacitor (HSC) device was assembled with activated carbon (AC) as an anode. Benefitting from the high capacity of the NiS cathode and the large voltage window of the device, the NiS-15//AC HSC showed a high energy density (Ed) of 43.57 W h kg-1 at 936.92 W kg-1, and the NiS-5//AC HSC provided an inferior Ed of 37.89 W h kg-1 at 954.79 W kg-1. Both HSCs showed excellent cycling performance over 6000 cycles at 10 A g-1. The experimental findings suggest that both NiS-15 and NiS-5 in this study can serve as potential cathodes for high-performance supercapacitors. This current synthesis method is simple and can be extended to the preparation of other transition metal sulfide (TMS)-based electrode materials with exceptional electrochemical properties.

High-Performance Battery-Type Supercapacitors Based on Self-Oriented Growth of Nanorods/Nanospheres Composite Assembled on Self-Standing Conductive GO/CNF Frameworks.

MnOx-based materials have limited capacity and poor conductivity over various voltages, hampering their potential for energy storage applications. This work proposes a novel approach to address these challenges. A self-oriented multiple-electronic structure of a 1D-MnO2-nanorod/2D-Mn2O3-nanosphere composite was assembled on 2D-graphene oxide nanosheet/1D-carbon nanofiber (GO/CNF) hybrids. Aided by K+ ions, the MnO2 nanorods were partially converted to Mn2O3 nanospheres, while the GO nanosheets were combined with CNF through hydrogen bonds resulting in a unique double binary 1D-2D mixed morphology of MnO2/Mn2O3-GO/CNF hybrid, having a novel mechanism of multiple Mn ion redox reactions facilitated by the interconnected 3D network. The morphology of the MnO2 nanorods was controlled by regulating the potassium ion content through a rinsing strategy. Interestingly, pure MnO2 nanorods undergo air-annealing to form a mixture of nanorods and nanospheres (MnO2/Mn2O3) with a distinct morphology indicating pseudocapacitive surface redox reactions involving Mn2+, Mn3+, and Mn4+. In the presence of the GO/CNF framework, the charge storage properties of the MnO2/Mn2O3-GO/CNF composite electrode show dominant battery-type behavior because of the unique mesoporous structure with a crumpled morphology that provides relatively large voids and cavities with smaller diffusion paths to facilitate the accumulation/intercalation of charges at the inner electroactive sites for the diffusion-controlled process. The corresponding specific capacity of 800 C g-1 or 222.2 mAh g-1 at 1 A g-1 and remarkable cycling stability (95%) over 5000 cycles at 3 A g-1 were considerably higher than those of the reported electrodes of similar materials. Moreover, a hybrid supercapacitor device is assembled using MnO2/Mn2O3-GO/CNF as the positive electrode and activated carbon as the negative electrode, which exhibits a superior maximum energy density (∼25 Wh kg-1) and maximum power density (∼4.0 kW kg-1). Therefore, the as-synthesized composite highlights the development of highly active low-cost materials for next-generation energy storage applications.

Versailles Santa Barbara-5 derived bifunctional one-dimensional electrocatalysts of hierarchical Ni3S2 nanoprism@nanosheets arrays for self-supporting and binder-free efficient supercapacitor and methanol oxidation reaction

We herein present a structure consisting of two-dimensional (2D) single-crystal Ni3S2 nanosheets designed on one-dimensional (1D) Ni3S2 nanoprism arrays (also known as Ni3S2 nanoprism@nanosheets). These arrays are directly synthesized over nickel foam, which is referred to as Ni3S2/NF. These structures can be used as binderless, self-supporting electrodes for bifunctional methanol oxidation reaction (MOR) applications and high energy density hybrid supercapacitors (HSC). Ni3S2/NF is synthesized through the two steps of hydrothermal processes. In step I, 1D hexagonal Versailles Santa Barbara-5 (VSB-5) nanorod arrays have been prepared onto the surface of NF (denoted as VSB-5/NF). The precursor for step II was 1D VSB-5 nanorod arrays, which were transformed into Ni3S2 using Na2S as a sulfur source via the Kirkendall effect. Electrochemical examination results show that as-synthesized Ni3S2/NF electrode exhibited a high specific capacitance (Cs) of 145.0 mA h g−1 at 5 A g−1, low series resistance (0.18 Ω) and charge-transfer resistance (0.05 Ω), small relaxation time constant (τ0 = 8 ms) and high frequency response at 125.8 Hz. Ni3S2/NF has a superior specific capacity of 145.0 mA h g−1 at 5 A g−1 as a SC electrode. The Ni3S2/NF//CNTs/NF HSC can be operated up to 1.6 V in a 3 M KOH electrolyte, delivering an impressive energy density of 256.35 W h kg−1 at a power density of 6400 W kg−1. The as-assembled Ni3S2/NF//CNTs/NF HSC device exhibited an impressive stability of 81 % even after undergoing 10,000 charge-discharge cycles. When compared to previously reported catalysts, Ni3S2/NF was proved to be an excellent electrocatalyst for MOR due to its ability to generate a current density of 215.0 mA cm−2 at 0.5 VSCE, while maintaining a superior and stable current density of 619.2 mA cm−2 at 0.8 VSCE.

Review of Battery-type Transition Metal (Cu, Co, and Ni) Oxide Based Electrodes: From Fundamental Science to Fabrication of a Hybrid Supercapacitor Device

Review of Battery-type Transition Metal (Cu, Co, and Ni) Oxide Based Electrodes: From Fundamental Science to Fabrication of a Hybrid Supercapacitor Device

Compositionally Tunable Mn-V-Fe Phosphoselenide Nanorods with Minimal Ion-Diffusion Barrier as High Energy Density Battery Electrode Materials.

The design and synthesis of novel heterostructured electrode materials are crucial to enable the fabrication of efficient supercapacitor devices. In this regard, transition metal phosphochalcogenides (S, Se) are promising candidates owing to their exotic electronic properties. Herein, a facile two-step hydrothermal protocol was used to synthesize binary and ternary metal phospho-selenide electrodes (Mn-Fe-P-Se, V-Fe-P-Se, Mn-V-P-Se, and Mn-Fe-V-P-Se). The chemical composition, morphology, and structure of the as-fabricated materials were fully investigated. The three-electrode electrochemical evaluation at 1.0 A g-1 demonstrated that the ternary metal electrode (MFVP-Se) exhibits a high capacity of 1968.63 C g-1. To assess the practical value of the rationally designed Mn-Fe-V-P-Se electrode material, Mn-Fe-V-P-Se was used as a positive electrode coupled with activated carbon (AC) as a negative electrode to assemble a hybrid supercapacitor device. This Mn-Fe-V-P-Se//AC device delivers a power density of 1999.96 W kg-1 with a high energy density of 149.88 Wh kg-1 coupled with no capacity loss after 5000 charging/discharging cycles. Additionally, density functional theory calculations revealed that our electrode exhibits suitable adsorption energy for OH- ions with a minimal diffusion barrier for ions.