ASC Device Research Articles

Electrochemical performance of MWCNT nanowires-decorated ZnCo2O4 sphere nanocomposite for an asymmetric capacitor

A composite material consisting of porous ZnCo2O4 sphere covered with MWCNT nanowires is synthesised using a hydrothermal technique and thermal annealing. The capacitive properties of the electrode materials are examined. The ZnCo2O4/MWCNT composites have superior capacitive performance in comparison to pure ZnCo2O4 hexagonal nanoplates. The ZnCo2O4/MWCNT composites have a specific capacitance of 2080 F/g at 1 A g−1. The cells also exhibit outstanding rate capacity, maintaining 600 F/g even at 5 A g−1. The nanocomposites have exceptional retention rate, as seen by an only 4.7 % decrease in specific capacitance over 10,000 cycles. The improved capacitive efficiency of ZnCo2O4/MWCNT composites may be ascribed to the structural benefits of large surface area, excellent electrical characteristics, and a well-established network provided by the MWCNT support. The ASC device has a significant energy density of 52.74 Whkg−1 while operating at a power density of 4205 Wkg−1. Additionally, it has an operating voltage window of 0–1.6 V. The excellent capacitive performance shows the potential use of ZnCo2O4/MWCNT composites as electrodes for hybrid capacitors.

Promising transition metal molybdate (TMM) single phase microstructures for asymmetric supercapacitor and photocatalytic applications

The increasing impact of worldwide energy challenges has sparked significant interest in developing multifunctional nanomaterials for energy and environmental applications. Among semiconductor photocatalysts, stable mixed metal molybdate materials have garnered much interest regarding energy storage and photocatalytic dye degradation. In this context, we have synthesized three different single-phase metal molybdates (NiMoO4, MnMoO4, and Fe2(MoO4)3) using the gel matrix method. XRD and Raman were executed to confirm phase formation of the acquired materials. Difference in surface morphology of synthesized transition metal molybdate powders was examined using SEM analysis. The energy-storing properties of synthesized transition metal molybdate powders were analyzed and compared using three and two electrode method. At a 1 Ag-1 current density, the as-synthesized NiMoO4, MnMoO4, and Fe2(MoO4)3 nanostructures exhibit specific capacitances of about 424.6, 325.5 and 157.8 Fg-1, respectively. Furthermore, the fabricated ASC device with NiMoO4 shows 41.6 Whkg-1 and 750 Wkg-1 as maximum energy and power density at 1 Ag-1, respectively. Meanwhile, photocatalytic methylene blue degradation was carried out using the as-synthesized materials as photocatalysts. The Fe2(MoO4)3 effectively decolourizes the dye with a maximum efficiency of 82.7 %, when compared to other two metal molybdate powders. Thus, the results show that the synthesized metal molybdates such as NiMoO4, and Fe2(MoO4)3 can act as potent electrode materials and efficient photocatalysts for energy storage and dye degradation applications when compared to MnMoO4.

Thiol-functionalized conductive Co-MOF and its derivatives S-doped Co(OH)2 nanoflowers for high-performance supercapacitors

The low conductivity of many traditional metal–organic-framework (MOF)-based electrode limits their developments in the field of electrochemical energy storage and still of great challenge. The controllable preparation of various kinds of nanomaterials using thiol-functionalized MOF shows great prospects. In this work, a thiol-functionalized metal–organic framework sheet structure (Co-MOF/NF) on nickel foam was successfully prepared by in situ interfacial growth synthesis, which was transformed into its derivatives S-doped β-Co(OH)2 nanoflowers Co-x/NF (x = 1, 2 and 6) in different concentrations of KOH solutions through ion etching/exchange reaction. The pristine thiol-functionalized Co-MOF/NF and its derivatives Co-x/NF (x = 1, 2 and 6) nanoflower-like arrays could be used as positive electrode materials for effective supercapacitors. Among them, the transformation of the nanoflower-like Co-1/NF electrode exhibits excellent electrochemical properties with high areal capacitance (1925 ± 23 mF/cm2 at 1 mA/cm2), good rate performance, excellent conductivity and decent cycling stability. The Co-1//AC ASC device provides a high energy density of 0.176 mWh/cm2 (92.6 Wh/kg) at a power density of 0.745 mW/cm2 (392.1 W/kg). And this Co-1//AC ASC device exhibits a good cycling stability and practical application in energy storage field. This study provides a new strategy for the pristine thiol-functionalized MOF and its conversion nanostructures for energy storage applications.

Potential difference-induced electrodeposition of defect-rich α-cobalt hydroxide on porous copper (PCu): High-voltage performance of supercapacitor

Designing electrode materials for aqueous battery-type supercapacitors to extend the operating voltage window remains a significant challenge to increase the energy density of aqueous supercapacitors. In this work, a directional electrodeposition method without any additives was employed to deposit α-Co(OH)2 onto a porous copper (PCu) current collector substrate, which involves the fabrication of a supercapacitor electrode material with a cross-linked network structure named α-Co(OH)2@PCu900. The potential difference between copper and cobalt facilitated the formation of a larger interlayer spacing for α-Co(OH)2. In addition, crystals of α-Co(OH)2 with different orientations exert stress on one another, leading to lattice distortion and vacancy formation. The morphology and microstructure of materials were analyzed through techniques such as SEM, HRTEM, XRD, and XPS, confirming the validity of the experimental design. This defect-rich, large interlayer spacing structure facilitates ion intercalation and deintercalation during the charge-discharge process, thereby expanding the operating voltage window. In a three-electrode system, α-Co(OH)2@PCu900 exhibited a potential range from −0.45 V to 0.55 V and demonstrated an areal capacitance of 2580 mF cm−2 and specific capacitance of 600 A g−1 at 2 mA cm−2. The α-Co(OH)2@PCu900 was used as the cathode material and commercial reduced graphene oxide (rGO) was used as the anode material in an asymmetric supercapacitor, and the ASC device exhibited an areal capacitance of 295.3 mF cm−2 and a specific capacitance of 87.89 F g−1. Notably, it retained a high energy density of 0.12 mW h cm−2 (35.27 Wh kg−1) at a power density of 1.7 mW cm−2 (505.95 W kg−1). This method established α-Co(OH)2@PCu900 as a promising supercapacitor electrode material, providing a viable strategy for designing and fabricating functional electrode materials.

High-performance asymmetric supercapacitor based on hierarchical hydrothermally grown CuS nanostructures

In this work, various hierarchical CuS were fabricated via an efficient one-step hydrothermal process with different surfactants (polyvinyl pyrrolidine (CS-P), Citric acid (CS-C), Oleic acid (CS-O)) and examined as electrode materials for supercapacitors. XRD, FESEM, HRTEM and BET analysis reveal the fabrication of a hexagonal crystal structure with porous microspheres of CuS-PVP having a BJH pore diameter of 16.241 nm. Among these, the CS-P electrode exhibits a superior specific capacitance of 414.28F/g at 1 A/g of current density in the KOH electrolyte. Additionally, an asymmetric supercapacitor built with CS-P as positive and Activated carbon as negative electrodes exhibited a specific energy of 27.95 Wh/kg at 624.96 W/kg of specific power at 2 A/g and demonstrated outstanding cycling stability with 80.6 % persistence of capacitance for 2500 GCD cycles at 10 A/g. Additionally, an ASC device created for use in real life and tested by charging it for 30 s managed to reach a 3-minute 50-second self-discharging duration. Hence, these favourable electrochemical findings indicate that the hydrothermally grown hierarchical CuS-PVP electrode is a bright potential material in energy storage applications.

Hierarchical nanostructured Co0.5Mn0.5WO4 efficient electrode material for asymmetric supercapacitor application

BackgroundThis research focuses on the electrochemical characteristics of binary metal tungstates for asymmetric supercapacitor applications. Metal tungstates such as Cobalt tungstate (CoWO4) and Manganese tungstate (MnWO4) exhibit excellent electrical conductivity and redox characteristics. Different combinations of binary metal tungstates can serve as effective electrode materials for supercapacitor applications. MethodHerein, Co0.5Mn0.5WO4 nanoparticles was synthesized by the co-precipitation method followed by calcination. The prepared nanoparticles was used as an electrode material for the supercapacitor application. For study the two electrode system, Co0.5Mn0.5WO4 and activated carbon were worked as anode and cathode electrode, respectively. Significant findingsThe prepared electrode materials exhibit a battery type pusudocapacitance in cyclic voltammetry (CV). The charging and discharging properties of the material was analysed by galvanic charging and discharging (GCD) studies and it displays the specific capacitance value of 444 F/g at the current density of 1 A/g and it shows the specific capacitance retention of 91% after 1500 cycles. AC//Co0.5Mn0.5WO4 ASC device shows good energy density, power density and specific capacitance values of 30.5 Wh/Kg, 2800 W/Kg and 112 F/g at 1 A/g current density, respectively.

Facile synthesis of Zn2V2O7/RGO nanocomposite for enhancing the electrochemical performance and evaluating the supercapacitor device

Pyrochlore-structured zinc vanadium oxide with RGO (Zn2V2O7/RGO) composite was synthesized using the simple hydrothermal process for energy storage device fabrication. The structural, vibration spectrum, surface morphology, and elemental of the Zn2V2O7/RGO composite were analyzed using different analytical methods. Then, the electrochemical performance was examined using Zn2V2O7/RGO composite modified electrode with 3-electrode and 2-electrode setup by cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectrum (EIS) techniques. Consequently, the Zn2V2O7/RGO composite revealed notable pseudo-capacitive behavior which has been confirmed through CV analysis. The nano size-based Zn2V2O7/RGO composite electrode material obtained notable specific capacitance (Csp) of 1400.51F/g owing to the synergistic promotion of Zinc and vanadium oxides. Furthermore, the ASC device of Zn2V2O7/RGO ||RGO displayed the efficient power density of 1371 kW/kg at the energy density of 8Wh/kg and the device has enhanced cycling performance with 72.8 % capacitance.

Morphologically tailored NiMn2O4nanocubic material for high energy-power density asymmetric supercapacitor and non-enzymatic H2O2 sensing

Developing an advanced material for energy storage and sensors is considered a key solution to meet future energy demands and economic challenges. The inverse spinel-structured NiMn2O4 emerges as a promising electrode material for next-gen energy storage due to its notable power capability, high energy density, and excellent cyclic stability. Nanostructuring enhances features not achievable in bulk materials, with a mixed morphology of nano-cubic and nanoflakes optimizing surface-to-volume ratio for effective use in energy storage devices. The addition of PVP as a surfactant, transforms the diffusion-controlled behavior to a capacitive mechanism, enhancing energy density and cyclic stability. Electrodes exhibit a specific capacitance of 816 F g−1 at 1 A g−1 and stable cyclic behavior over 5000 cycles in 1 M KOH. The constructed ASC device shows 96% cyclic stability over 10,000 cycles, maintaining an energy density of 8.8 Wh kg−1 at 6400 W kg−1 and reaching a maximum of 36.55 Wh kg−1 at 400 W kg−1. Electronic structural characteristics explained through density functional theory (DFT) contribute insights. Furthermore, the non-enzymatic NiMn4/GCE H2O2 sensor demonstrates high sensitivity, a low detection limit, and remarkable selectivity against various biological interferences across a broad concentration range.

Uniform P-Doped MnMoO4 Nanosheets for Enhanced Asymmetric Supercapacitors Performance.

Manganese molybdate has garnered considerable interest in supercapacitor research owing to its outstanding electrochemical properties and nanostructural stability but still suffers from the common problems of transition metal oxides not being able to reach the theoretical specific capacitance and lower electrical conductivity. Doping phosphorus elements is an effective approach to further enhance the electrochemical characteristics of transition metal oxides. In this study, MnMoO4·H2O nanosheets were synthesized on nickel foam via a hydrothermal route, and the MnMoO4·H2O nanosheet structure was successfully doped with a phosphorus element using a gas-solid reaction method. Phosphorus element doping forms phosphorus-metal bonds and oxygen vacancies, thereby increasing the charge storage and conductivity of the electrode material. The specific capacitance value is as high as 2.112 F cm-2 (1760 F g-1) at 1 mA cm-2, which is 3.2 times higher than that of the MnMoO4·H2O electrode (0.657 F cm-2). The P-MnMoO4//AC ASC device provides a high energy density of 41.9 Wh kg-1 at 666.8 W kg-1, with an 84.5% capacity retention after 10,000 charge/discharge cycles. The outstanding performance suggests that P-MnMoO4 holds promise as an electrode material for supercapacitors.

Urchin-like Ce(HCOO)3 Synthesized by a Microwave-Assisted Method and Its Application in an Asymmetric Supercapacitor.

In this work, a series of urchin-like Ce(HCOO)3 nanoclusters were synthesized via a facile and scalable microwave-assisted method by varying the irradiation time, and the structure-property relationship was investigated. The optimization of the reaction time was performed based on structural characterizations and electrochemical performances, and the Ce(HCOO)3-210 s sample shows a specific capacitance as high as 132 F g-1 at a current density of 1 A g-1. This is due to the optimal mesoporous hierarchical structure and crystallinity that are beneficial to its conductivity, offering abundant Ce3+/Ce4+ active sites and facilitating the transportation of electrolyte ions. Moreover, an asymmetric supercapacitor based on Ce(HCOO)3//AC was fabricated, which delivers a maximum energy density of 14.78 Wh kg-1 and a considerably high power density of 15,168 W kg-1. After 10,000 continuous charge-discharge cycles at 3 A g-1, the ASC device retains 81.3% of its initial specific capacitance. The excellent comprehensive electrochemical performance of this urchin-like Ce(HCOO)3 offers significant promise for practical supercapacitor applications.

Construction of MoB@LDH heterojunction and its derivates through phase and interface engineering for advanced supercapacitor applications

Layered double hydroxide (LDH) has been attracted widespread attention in supercapacitor due to their unique layered structure and associated advantages. However, the inherent limitations of low electrical conductivity and reaction kinetics rate of LDH restrict its widespread application. Various modification techniques, such as heterojunction formation, phosphorization and introduction of phosphorus vacancies, are employed to modify LDH with the goal of improving the electrochemical performance. Preparation of composite materials using MoB MBene as conductive template and phosphorization are the effective ways for enhancing the electrical conductivity of electrode materials. MoB MBene is prepared using a modified method that combines NaOH etching and a high-temperature hydrothermal process. The presence of phosphorus vacancy is beneficial for enhancing the kinetics rate during electrode reactions. Through the synergistic effect of various modification methods, MP2 demonstrates an optimal electrochemical performance with a superior specific capacitance of 1731.19F/g (238.28 mAh g−1) at 1 A/g. It also demonstrates an impressive rate capacity of 81.28 % at 10 A/g and maintains a satisfactory capacitance retention of 88.14 % after 5000 cycles. In addition, a fabricated MP2//AC ASC device achieves an impressive energy density of 39.91 Wh kg−1 at the power density of 948.25 W kg−1 and demonstrates satisfactory cycling stability of 78.76 % after 5000 cycles. This work presents a comprehensive framework for analyzing the impact of material structure, components, and crystal phases on energy storage performance. It also examines the regulatory impact of different modification methods on energy storage mechanisms.

Effect of Zn/Mn on the supercapacitor behavior of high-entropy FeCoNiCrZn/Mn alloy

Figure (a) Synthesis of the Zn inclusion nanostructured HEA and the SEM image of the same, (b) Ragone plot for the ASC device and (c) ‘k2’ value for the FeCoNiCr (Zn and Mn) HEA at 0.3 V.

Fabrication of nanoflower-like Ni2Co-S/CNTA with morphology controlled for high-performance supercapacitor

Morphology and structure regulation is considered to be an effective strategy to improve the energy storage performance of supercapacitor electrode materials. In this work, a series of graded Ni2Co-S/CNTA nanoflowers composed of self-assembled nanosheets or nanorods have been synthesized by nitrilotriacetic acid (NTA)-assisted hydrothermal strategy. Morphological analysis shows that the micromorphology of the unit structures made up nanoflowers can be controlled by adjusting the concentration of NTA. Thanks to the synergistic effect of high void space, hierarchical assembly mode and integrated composite structure, Ni2Co-S/CNTA nanoflowers promote the full exposure of rich active sites, it enhances the stability of the structure, and impart excellent energy storage performance. As expected, the optimized Ni2Co-S/CNTA-2 electrode exhibits excellent capacitive performance, including high specific capacitance (1670.2 F g−1 at 1.0 A g−1) and good cycle stability (86.5% after 5000 cycles). The maximum energy density of Ni2Co-S/CNTA-2//AC ASC device is 61.3 Wh·kg−1 at a power density of 816.7 W·kg−1 and its retention rate is 88.3% after 5000 cycles.

Enhanced asymmetric supercapacitor device performance of graphene templated β-Bi2-xEuxMo2O9 nano self-assembly

The electrode material plays a crucial role in the performance of energy storage devices. Currently, the research focuses on enhancing the super-capacitive nature of the existing electrode materials in many ways. Herein, the influence of rare earth ions in the electrochemical characteristics of β-Bi2-xEuxMo2O9 and graphene-modified GrM-β-Bi2-xEuxMo2O9 is investigated. The gel matrix method is adopted for synthesizing the Bi2-xEuxMo2O9 (x = 1, 5 and 10 %) and GrM - Bi2-xEuxMo2O9 (x = 5,10 %). The as-synthesized material's structural formation, phase purity and structural modifications are studied using XRD, Raman and SEM. The chemical composition with their oxidation state is verified using XPS analysis. The electrochemical behavior of the pristine materials is examined with various analyses such as CV, GCD and EIS techniques in both three-electrode and two-electrode systems. The specific capacitance of GrM-Bi1.8Eu0.2Mo2O9 is 904 F/g at 1 A/g with excellent cyclic stability of about 82.14 % at 5 A/g after 5000 cycles. An ASC device developed using GrM-Bi1.8Eu0.2Mo2O9 exhibits columbic efficiency of 96.5 % with an extended cyclic life of 76.9 % after 10,000 cycles. The fabricated device possesses energy density and power density of 60.21 W h Kg−1 and 750 W Kg−1, respectively, at 1 A/g, acting as a favorable candidate for supercapacitor application.

Sodium carboxymethylcellulose/MXene/zeolite imidazolium framework-67-derived 3D porous carbon aerogel for high-performance asymmetric supercapacitors

Herein, we propose a carbon/TiO2/Co3O4 (CTC) composite carbon aerogel with a 3D porous conductive network structure derived from sodium carboxymethylcellulose (CMC)/Mxene (Ti3C2Tx)/zeolite imidazolium framework-67 (ZIF-67). Among them, CMC is used as the carbon skeleton, which can reduce the powdering caused by volume change and improve the cycle stability. Ti3C2Tx acts as the conductive agent and dispersant for ZIF-67, exposing more reactive sites while constructing fast conductive channels to enhance electrochemical performance. The microstructure of the CTC carbon aerogel is modulated by controlling the mass ratio of Ti3C2Tx to ZIF-67, and the carbon aerogel with a mass ratio of 2:3 (CTC-2:3) is experimentally demonstrated to have the best electrochemical performance. The CTC-2:3 electrode exhibits a high specific capacitance of 481.7 F g−1 at 1 A g−1 and possesses a rate performance of 78.9 % at 10 A g−1. The assembled asymmetric supercapacitor (ASC, CTC-2:3//Ti3C2Tx) delivers an energy density of 48.4 Wh kg−1 at a power density of 699.8 W kg−1. Moreover, the ASC device maintains 85.3 % initial capacitance and 99.1 % coulombic efficiency after 10,000 GCD cycles, indicating good cycling stability. This facile design pathway provides a new insight for the development of high-performance electrode materials.

Cobalt oxide decorated 2D MXene: A hybrid nanocomposite electrode for high-performance supercapacitor application

The 2D layered material, MXene has incited a lot of interest in energy storage research due to its high metallic conductivity, high hydrophilicity, high energy storage capability, biocompatibility, and excellent electrochemical activity due to rich surface chemistry. However, the restacking of MXene layers lowers the number of active sites in MXene, which in turn limits the use of MXene in supercapacitors. Furthermore, the narrow working potential window of MXene limits the energy density of the electrodes. To address these issues and improve the electrochemical performance of MXene, several hierarchical MXene/transition metal oxide composites have been synthesized and characterized. This work explores MXene and its composites with cobalt oxide nanoparticles for supercapacitor applications. The Co@MXene composite was synthesized by using a one-pot hydrothermal method. As prepared, the nanocomposite exhibited a specific capacitance of 732.5 F g−1 at 1 A g-1 current density and excellent cycling stability of 83% over 5000 cycles. The as-fabricated ASC device (Co@MXene-2//AC) demonstrates the maximum energy density of 26.6 Wh Kg−1 at 700 W Kg−1 power density. The above results illustrate that MXene/transition metal oxide nanocomposite can be an alternative to enhance electrochemical performance for energy storage applications.

Uniform Co9S8 nanosheets on carbon nanotube arrays grown on Ni mesh as free-standing electrodes for asymmetric supercapacitors

A free-standing 3D core/shell composite material CNTs@Co9S8 on nickel mesh has been prepared by a simple two-step method. Carbon nanotubes (CNTs) grown vertically on the surface of nickel mesh by chemical vapor deposition (CVD) method act as conductive skeleton. Then Co9S8 nanosheets uniformly aligned on the surface of the CNTs by solvothermal method are interconnected to form a honeycomb structure. Owing to the close contact of the CNTs@Co9S8 hybrid with the nickel mesh and the hierarchical 3D porous structure, the prepared Ni@CNTs@Co9S8 electrodes exhibit low resistance and excellent charge storage capability with a specific capacitance of 1305.4 F g−1 at 1 A g−1. The composite delivers an excellent rate capability with 84.3 % capacitance retention at 10 A g−1. An asymmetric supercapacitor composed of Ni@CNTs@Co9S8 and nitrogen-doped carbon nanotubes (NCNTs) shows an energy density of 23.8 Wh kg−1 and a high power density of 8007.4 W kg−1. The specific capacitance of the ASC device remained 87.31 % after 10,000 charge-discharge cycles and two tandem ASCs can power two red LED diodes for at least 7 min, suggesting the potential application of the obtained free-standing electrode for supercapacitors.

Ni0.85Se anchored on N-doped MoSe2 hybrids for long-life asymmetric supercapacitors

The layered molybdenum diselenide (MoSe2) is an ideal electrode material for supercapacitors. However, its widespread application is severely hampered due to low capacity, poor rate performance, and inferior cycling durability. Herein, the Ni0.85Se anchored on N-doped MoSe2 (Ni0.85Se/N-MoSe2) hybrids have been successfully produced using a facile hydrothermal route, in which formamide and water served as the mixed solvent. Compared to the Ni0.85Se or N-MoSe2, the specific capacity of Ni0.85Se/N-MoSe2 hybrids was substantially enhanced due to the cooperative effect between Ni0.85Se and N-doped MoSe2 as well as unique mesoporous architecture. The Ni0.85Se/N-MoSe2 hybrids could deliver 276.5 C g−1 at 250 mA g−1. Moreover, a Ni0.85Se/N-MoSe2//activated carbon (AC) asymmetric supercapacitor (Ni0.85Se/N-MoSe2//AC ASC) could offer 58.4 F g−1 at 500 mA g−1, and a considerable energy density of 20.8 Wh kg−1 at 200 W kg−1. Impressively, the Ni0.85Se/N-MoSe2//AC ASC demonstrated outstanding cyclic durability (105.1 % of initial capacity could be retained after 15,000 cycles at 1000 mA g−1). A Ni0.85Se/N-MoSe2//AC ASC device could drive a timer for about 15 min. Therefore, the Ni0.85Se/N-MoSe2 hybrid is a promising positive electrode material for ASCs.

Structural reconstruction of N/S-assisted carbon polyhedral matrix endowed with bimetallic phosphide heterostructures for energy storage

The synergism of heteroatom-doped carbon polyhedral with mixed-metal networks offers a myriad of electroactive sites that aid in excellent capacitive performance. Herein, a simple precipitation method was implemented to synthesis thiourea functionalized bimetallic ZIF-67 polyhedral as a sacrificial template, facilitating the construction of a superior N/S‑carbon matrix with a Co-Ni-P (CNS/CNP) architecture through various thermal phosphorization processes. The CNS/CNP-2 revealed remarkable attributes after phosphorization at 500 °C, including a maximum specific capacitance of 588 F g−1 at a specific current of 1 A g−1 in 3 M KOH electrolyte. This outstanding performance arises from the synergy of N/S carbon matrix, which significantly increases electroactive sites and structural stability, and Co-Ni-P network, which enhances both redox-active site density and conductivity, facilitating rapid ion diffusion. Furthermore, an asymmetrical supercapacitor was integrated as CNS/CNP-2//AC and revealed a maximum specific energy and power of 30.3 W h kg−1 and 12,489 W kg−1, respectively, with capacitance retention of 90% even for 10,000 cycles. The ASC device was designed as a coin-cell to facilitate real-time applications. The study demonstrates that a synergistic effect between CoNi metal ions and a heteroatom matrix can yield an electrode material with a high specific capacity for energy storage devices.

Cu-Metal Organic Framework Derived Multilevel Hierarchy (Cu/CuxO@NC) as a Bifunctional Electrode for High-Performance Supercapacitors and Oxygen Evolution Reaction.

The development of a MOFs-derived multilevel hierarchy in a single step still remains a challenging task. Herein, we have synthesized novel Cu-MOF via a slow diffusion method at ambient temperature and further utilized it as a precursor source for MOF-derived multilevel hierarchy (Cu/CuxO@NC, x = 1 and 2). This studies suggest that the organic ligands served as a source of an N-doped carbon matrix encapsulated with metal oxide nanoparticles which were confirmed by various characterization techniques; further BET analysis reveals a surface area of 178.46 m2/g. The synthesized multilevel hierarchy was utilized as an electro-active material in a supercapacitor that achieved a specific capacitance of 546.6 F g-1 at a current density of 1 A g-1 with a higher cyclic retention of 91.81% after 10 000 GCD cycles. Furthermore, the ASC device was fabricated using Cu/CuxO@NC as the positive electrode and carbon black as the negative electrode and utilized to enlighten the commercially available LED bulb. The fabricated ASC device was further employed for a two-electrode study which achieved a specific capacitance of 68 F g-1 along with a comparable energy density of 13.6 Wh kg-1. Furthermore, the electrode material was also explored for the oxygen evolution reaction (OER) in an alkaline medium with a low overpotential of 170 mV along with a Tafel slope of 95 mV dec-1 having long-term stability. The MOF-derived material has high durability, chemical stability, and efficient electrochemical performance. This work provides some new thoughts for the design and preparation of a multilevel hierarchy (Cu/CuxO@NC) via a single precursor source in a single step and explored multifunctional applications in energy storage and an energy conversion system.