High-performance Asymmetric Supercapacitors Research Articles

Facile synthesis of MnMoO4 nanostructures arrays as novel electrode materials for high-performance symmetric and asymmetric supercapacitor

Facile synthesis of MnMoO4 nanostructures arrays as novel electrode materials for high-performance symmetric and asymmetric supercapacitor

Green Synthesis of ZnO Nanoparticles and Ag-Doped ZnO Nanocomposite Utilizing Sansevieria trifasciata for High-Performance Asymmetric Supercapacitors.

This study provides a comprehensive analysis of a biofabricated nanomaterial derived from Sansevieria trifasciata root extract, evaluating its structural, morphological, and optical properties for use in asymmetric supercapacitors. The nanomaterial comprises pristine ZnO nanoparticles (ZnO NPs) and a 1% Ag-doped ZnO nanocomposite (Ag@ZnO NC), synthesized through a green-assisted sol-gel autocombustion method. Employing techniques such as X-ray diffraction, ultraviolet-visible near-infrared, scanning electron microscopy-energy-dispersive X-rayspectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, and transmission electron microscopy, the study confirms a hexagonal wurtzite structure and nanocrystallites with spherical and hexagonal shapes (30 nm). Optical analysis reveals a red shift in the band gap with Ag doping, indicating improved conductivity. The material shows potential applications in solar cells, optoelectronics, spintronics, wastewater treatment, and high-performance asymmetric supercapacitors. Raman spectra validate the wurtzite phase and identify intrinsic defects. Electrochemical tests demonstrate remarkable supercapacitive behavior with a 94% capacitance retention after 10,000 cycles, highlighting its promise as advanced asymmetric supercapacitors.

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.

Photo-assisted charging of heterostructured NiCo2S4@NiCo-LDH composite electrode with remarkable photoelectronic memory effect for high-performance asymmetric supercapacitor

Rational establishment of photo-assisted supercapacitor represents a viable strategy for achieving solar energy conversion and storage. In this study, NiCo2S4@NiCo-LDH (NCS@NC-LDH) composite electrode was effectively synthesized for a highly efficient asymmetric supercapacitor (ASC). Specific capacitance of NCS@NC-LDH under light condition (3286.25 F g−1 at 1 A g−1) demonstrated notable improvement in contrast to that under dark condition (2171.5 F g−1 at 1 A g−1). Meanwhile, NCS@NC-LDH displayed strong photoelectronic memory, as a merely 3 % specific capacitance decreased when discharged under dark compared to that of continuous illumination. Additionally, the assembled aqueous ASC (NCS@NC-LDH//AC) exhibited substantial energy density (83.2 Wh kg−1 at 800 W kg−1) under light condition. Density functional theory (DFT) calculation further demonstrated that the formed matched band facilitated efficient generation-transfer of photoinduced electrons/holes and thus improved the energy storage behavior. We anticipated that this work may offer new perspectives on developing multi-component composite electrodes tailored for high-performance solar-driven electrochemical energy storage.

Controlled preparation of carbon cloth decorated with nanostructured Mn(OH)2/Mn3O4 electrodes for high-performance asymmetric supercapacitors

Environmentally friendly aqueous asymmetric supercapacitors are expected to exhibit excellent energy storage properties, stable performance, and facile production protocols. This study focused on the fabrication and characterisation of an asymmetric supercapacitor (ASC) with a commercial activated carbon (AC) negative electrode and Mn(OH)2/Mn3O4 composite on carbon cloth (hCC) positive electrode. The Mn-based electrode was synthesised using a one-step electrodeposition process. The morphology and crystalline structure of the composite electrode were modified by varying the deposition time of the Mn(OH)2/Mn3O4 nanostructures on carbon cloth substrate which greatly influence the electrochemical performance of the asymmetric systems. The best ASC used the AC electrode and a Mn(OH)2/Mn3O4@hCC electrode prepared using electrodeposition over an optimised time of 3 h. It exhibited a remarkable specific energy density of 40.7 Wh kg−1 at a power density of 100 W kg−1. In addition, this ASC demonstrated stable long-term performance, retaining 88 % of its capacitance after 5000 charge–discharge cycles, showing its great application potential in the field of supercapacitors.

Enhancing heterojunction interface charge transport efficiency in NiCo-LDHs@Co/CoO-CNFs for high-performance asymmetric and zinc-ion hybrid supercapacitors

The lack of active groups and poor dispersion of pristine carbon substrates lead to their inability to composite with other materials effectively, so that the electron transfer between them is inefficient. Therefore, in order to design carbon-based composites with high conductivity and electrochemical properties, the electron transfer between them must be enhanced first. Herein, the Co/CoO quantum dots doped carbon nanofiber (Co/CoO–CNF) materials with mesopore, high degree of graphitization and mechanical flexibility are synthesized via an electrospinning method. Then, ultrathin NiCo-LDHs are uniformly loaded on the Co/CoO-CNFs in situ to form NiCo-LDHs@Co/CoO-CNFs. Benefiting from the Fermi energy level difference and heterointerface between Co/CoO-CNFs (EF = −4.44 eV) and NiCo-LDHs (EF = −2.12 eV), electrons can be tansfered rapidly from NiCo-LDHs to Co/CoO-CNFs during the electrochemical reaction, so that NiCo-LDHs@Co/CoO-CNFs exhibit the excellent specific capacitance of 2055 F g−1 at 1 A g−1. When using in a flexible asymmetric supercapacitor, NiCo-LDHs@Co/CoO-CNFs shows a high energy density of 54.0 W h kg−1 at 760.0 W kg−1. Furthermore, assembled as the Zn-ion hybrid supercapacitor, NiCo-LDHs@Co/CoO-CNFs can also display an ultra-high energy density of 108 W h kg−1 at 914.8 W kg−1, as well as outstanding work durability (the capacitance of 98.2 % after 10,000 cycles).

Polytoluidine blue-coated multiwalled carbon nanotubes: In-situ polymerization based hybrid nanostructure for high performance asymmetric supercapacitors

In this work, a series of multiwalled carbon nanotubes/polytoluidine blue (MWCNTs/PTB) with network structure are synthesized by in-situ oxidative polymerization. Electrochemical performance of MWCNTs/PTB are optimized through precise control of mass ratio between two components. Field emission scanning electron microscope analysis reveals a more homogeneous dispersion of network structure under the mass ratio of 1:3. Prepared MWCNTs/PTB-3 electrode exhibits the highest specific capacity of 232.7C g−1 and satisfactory specific capacity retention of 91.9 % after 5000 charge/discharge cycles in 1.0 M H2SO4 electrolyte. Additionally, the assembled asymmetric supercapacitor exhibits energy density of 13.4 Wh kg−1 at power density of 600 W kg−1 and maintains exceptional cyclic stability. In conclusion, constructing carbon nanotube-supported conductive polymer composite proves to be an effective approach for enhancing the energy storage performance.

High-performance pristine ZIF-67 asymmetric supercapacitor device with excellent energy and power density for energy storage application

The current work describes a simple and safe method for creating ZIF-67 (zeolitic imidazolate framework-67) nanostructures. X-ray diffraction (XRD) patterns reveal that the material exhibits a cubic phase free from contaminating impact. The synthesized material has a notable porosity, a high specific surface area (SSA) of ∼ 1071 m2 g−1, and a clearly defined hexagonal shape with high-resolution transmission electron microscope (HRTEM) analysis. Moreover, the electrochemical analysis in the three-electrode setup shows an extraordinary specific capacitance (CS) of 472 F g−1 and exceptional cyclic performance of 91.6 % retention in a 6 M NaOH aqueous electrolyte. Furthermore, activated carbon (AC) is being used as the negative electrode and ZIF-67 as the positive electrode to design a device with a wide potential window (1.50 V). The outstanding performance of the Asymmetric supercapacitor (ASC) device is evident in its exceptional CS (358 F g−1). This, coupled with its remarkable energy (22 Wh kg−1) and power density (4164 W kg−1), highlights its suitability for demanding energy storage applications. Notably, the device demonstrates extraordinary cyclic stability, retaining over 132 % of its initial capacitance after 5000 charge-discharge cycles, solidifying its long-term reliability. Finally, LEDs (Light Emitting Diodes) of various colors are being illuminated using three series-connected devices. Hence, the recent work is illustrating the possible practical benefit of the ongoing development of supercapacitive energy storage systems.

Stepwise Construction of MoS2@CoAl-LDH/NF 3D Core-Shell Nanoarrays with High Hole Mobility for High-Performance Asymmetric Supercapacitors.

Supercapacitors (SCs) have received widespread attention as excellent energy storage devices, and the design of multicomponent electrode materials and the construction of ingenious structures are the keys to enhancing the performance of SCs. In this paper, MoS2 nanorods were used as the carrier structure to induce the anchoring of CoAl-LDH nanosheets and grow on the surface of nickel foam (NF) in situ, thus obtaining a uniformly distributed MoS2 nanorod@CoAl-LDH nanosheet core-shell nanoarray material (MoS2@CoAl-LDH/NF). On the one hand, the nanorod-structured MoS2 as the core provides high conductivity and support, accelerates electron transfer, and avoids agglomeration of CoAl-LDH nanosheets. On the other hand, CoAl-LDH nanosheet arrays have abundant interfacially active sites, which accelerate the electrolyte penetration and enhance the electrochemical activity. The synergistic effect of the two components and the unique core-shell nanostructure give MoS2@CoAl-LDH/NF a high capacity (14,888.8 mF cm-2 at 2 mA cm-2) and long-term cycling performance (104.4% retention after 5000 charge/discharge cycles). The integrated MoS2@CoAl-LDH/NF//AC device boasts a voltage range spanning from 0 to 1.5 V, achieving a peak energy density of 0.19 mW h cm-2 at 1.5 mW cm-2. Impressively, it maintains a capacitance retention rate of 84.6% after enduring 10,000 cycles, demonstrating exceptional durability and stability.

Application of Fe-based nanocomposites for the preparation of high-performance asymmetric supercapacitors

Application of Fe-based nanocomposites for the preparation of high-performance asymmetric supercapacitors

Facile Synthesis of 3D Cu(OH)2@NiCo-Binary Hydroxide Core–Shell Nanotube Arrays with High Mass Loading for High-Performance Asymmetric Supercapacitors

Facile Synthesis of 3D Cu(OH)₂@NiCo-Binary Hydroxide Core–Shell Nanotube Arrays with High Mass Loading for High-Performance Asymmetric Supercapacitors

Rational design of the binder-free polythiophene nanofibers deposited nickel foam for the high-performance aqueous asymmetric supercapacitor

Development of the binder-free electrode materials and employing in the supercapacitor is the essential footstep for high energy storage. The present study highlights the cost-effective synthesis strategy for the binder-free growth of the amorphous polythiophene nanofibers over the nickel foam substrate. The presence of functional bonds like CC, C-H, and C-S has confirmed the deposition of the polythiophene nanofibers on the nickel foam, while elemental mapping analysis detected the uniform distribution of Carbon and Sulfur elements over nanofibers. The surface structure of the polythiophene is transformed from nanofibers to a wire-like structure as the result of the monomer concentration variation. The optimized polythiophene film exhibited the highest areal capacitance of 1263.2 mF/cm2 at 2 mA/cm2 with 90.03% capacitance retention after 5000 cycles. Moreover, the aqueous asymmetric device (PTh//AC) is fabricated which delivered 31.5 F/g at 10 mA/cm2. The highest specific energy of PTh//AC device was 6.3 Wh/kg. Also, it showed good retention capability with 82.3% retention. Based on these results, the present investigation provides the performance metrics of the polythiophene nanofibers and highlights the potential utilization of the polythiophene-based supercapacitor in practical energy storage systems.

Microcubes of ZnSe–SnSe2 Encapsulated within Graphene for High-Performance Asymmetric Supercapacitors

Microcubes of ZnSe–SnSe₂ Encapsulated within Graphene for High-Performance Asymmetric Supercapacitors

Nickel-molybdenum bimetallic sulfide decorated biomass derived carbon support for high performance asymmetric supercapacitor application

Biomass - derived carbon electrode material with a porous structure is widely used in supercapacitor applications, which can improve electron transfer and shorter ion diffusion pathways. In this work, the garlic peel biomass carbon (GPBC), NiMo3S4(NMS) and garlic peel biomass carbon decorated with NiMo3S4 (GPBC/NMS) composite were prepared through a in situ two-step hydrothermal method. The synthesized materials were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), energy dispersive x-ray spectroscopy (EDS), Transmission electron microscopy techniques (TEM), Raman spectroscopy and Brunauer-Emmett-Teller (BET) techniques were used to analyze the structure, morphology and specific surface areas and X-ray photoelectron spectroscopy (XPS). The prepared bimetallic metal sulfide on a biomass - derived carbon namely the GPBC/NMS composite is used in supercapacitor application. The GPBC/NMS composite electrode exhibits good cycle performance with high specific capacity of 304C/g at current density of 1 A/g in a 3 M KOH electrolyte solution. The electrochemical performance of the GPBC/NMS//GPBC asymmetric supercapacitor device produces an excellent energy density 45.5 Wh kg−1 at a power density of 1125 W kg−1 in the 1.6 V operating potential window. The GPBC/NMS//GPBC also exhibits 93 % retention of its initial capacitance after the 10,000 GCD cycle performance. The above results demonstrate a new way of developing high performance electrode materials for energy storage applications.

Nickel-copper-cobalt mixed oxide electrode material for high performance asymmetric supercapacitor

Nickel copper cobalt oxide (NiCuCoO) ternary metal oxide nanoparticles were synthesized by employing the hydrothermal method. NiCuCoO electrode demonstrates a specified capacity of 596 C g−1 at 1 A g−1, high capacitance retaining of 99% even if 1000 sequences at the density of current 10 A g−1, and significant extended cyclic strength over 1000 sequences. The gathered asymmetric supercapacitor (ASC) tool via NiCuCoO as the cathode and activated carbon as anode materials achieve a specified capacity of 168 C g−1 at a current density of 1 Ag−1, an excellent capacity retaining of 95% even later than 5000 sequences at a density of current 10 A g−1. The fabricated device exhibits a high density of energy and power is 96 Wh kg−1 and 841 W kg−1. The prepared material confirms an excellent capacitance routine, so this work represents for a next-generation energy storage device.

Preparation of Positive and Negative Composite Electrode Materials for High-Performance Aqueous Asymmetric Supercapacitor by a Sequential Two-Step Reaction

Preparation of Positive and Negative Composite Electrode Materials for High-Performance Aqueous Asymmetric Supercapacitor by a Sequential Two-Step Reaction

3D Architecting triple gradient graphene-based fiber electrode for high-performance asymmetric supercapacitors

High-performance fibrous architectures and controllable fabrication methods for active nanomaterials are fundamental in the development of fiber-based supercapacitors (FSCs). Herein, we rationally designed a triple gradient structured fibrous electrode based on three-dimensional (3D) architectural approach with Ni3S2 nanoflakes (Ni3S2 NFs) in situ growth on Ni-coated graphene fiber (Ni3S2-NiGFs) for highly energy-dense asymmetric supercapacitors. Remarkably, the Ni-metal coating imparted the Ni3S2-NiGFs exceptional electrical conductivity (619.8 S cm−1), mechanical strength (335.0 MPa), and flexibility without significantly compromising its density. Moreover, the unique 3D interconnected ultrathin Ni3S2 NFs significantly increase the contact area between the electrode and the electrolyte solution, providing abundant redox activity to facilitate ion transport and accumulation. Therefore, the fibrous electrode showcased a remarkable areal specific capacitance of 1387.6 mF cm−2 at 3 mA cm−2 in 3 M KOHaq electrolyte, while its asymmetric FSCs delivered an impressive areal energy density of 15.6 μW h cm−2 at power density of 1.0 mW cm−2 along with durable cycle life (86.7 % of the initial specific capacitance retention over 10,000 cycles). In summary, the featured work provides a facile but robust electrode design to realize highly energy-dense flexible energy storage devices for next-generation wearable industries.

Fabrication of NiCo2O4@NiCo2S4 Core@Shell nanostructured arrays decorated over the rGO sheets for High-Performance asymmetric supercapacitor

Reliable and cost-effective energy storage systems can only be designed using electrode materials that exhibit high energy densities and consistency. In this work, NiCo2S4@NiCo2O4 core@shell nanoneedle-like nanostructures (NCS@NCO/rGO) are synthesized over the rGO sheet using a new and easy hydrothermal approach. Electrolyte transport and sulfur incorporation during charge–discharge reactions are both made easier by the core@shell nanostructured arrays' large active surface area. The ternary electrodes made of NCS@NCO/rGO have a rich mesoporous framework, a large surface area of 156.5 m2g−1, and an ideal distribution of pore sizes centered at 8.1 nm. An impressive specific capacitance of 2011 Fg−1 at 10 mV s−1 demonstrates the exceptional performance of the NCS@NCO/rGO ternary electrode. The ternary electrodes made of NCS@NCO and rGO have been shown to have remarkable cyclic stability in reports, maintaining 91 % of their capacity after 10,000 cycles. With an impressive power density of 983 Wkg−1 and an outstanding cycling durability of 98.8 % retention of the original capacitance after 10,000 cycles, the manufactured NCS@NCO/rGO//AC ACS displays a noticeable energy density of 68.5 Whkg−1. The mesoporous structure is excellent for increasing the characteristics of supercapacitor electrodes, as these astounding results can attest.

Lignosulfonate-Assisted Synthesis of Porous Carbon-Supported MnO2 Composites with Reinforced Interface Bonding for High-Performance Asymmetric Supercapacitors

Lignosulfonate-Assisted Synthesis of Porous Carbon-Supported MnO₂ Composites with Reinforced Interface Bonding for High-Performance Asymmetric Supercapacitors

Carbamide-mediated facile sol-gel synthesis of porous flower-like ZnCo2O4 microspheres for high-performance asymmetric coin cell supercapacitors

The design and development of ultrahigh-performance nanomaterials possessing novel characteristics are needed to achieve reliable energy storage performance. To satisfy the needs, diverse electrode materials are explored. Even though carbon-based materials hold high surface area and conductivity, their specific capacitance value fails to deliver high-performance applications. Therefore, pseudocapacitive transition metal oxide is adopted to overcome these issues. Among all Zinc Cobaltite, a binary transition metal oxide is widely explored owing to its fascinating electrochemical properties. As most of the synthesis of these kinds of materials requires the hydro/solvothermal method, herein, we have proposed the concept of a facile sol-gel method to prepare this class of materials by using Carbamide as both structure director and fuel to achieve the porous flower-like Zinc Cobaltite. The prepared material delivers the notable gravimetric specific capacitance of 513.3 F g−1. Owing to its unique morphology and porous structure, ion channelization is feasible, which will enhance the electrochemical reaction. Constructed asymmetric coin cell supercapacitor showed an extraordinary specific capacitance of 106.5 F g−1 and energy density of 56.2 Wh kg−1, demonstrating an impressive ability to retain 89.6 % of its capacitance after 4000 cycles at a current density of 6 A g−1. Due to the remarkable electrochemical behavior, this work can act as a guiding tool for designing efficient and cost-effective energy storage devices that will hold prodigious potential in commercial energy storage applications.