High-performance Supercapacitor Applications Research Articles

Design and preparation of NiCoS nanostructures on Ni foam for high-performance asymmetric supercapacitor application

Design and preparation of NiCoS nanostructures on Ni foam for high-performance asymmetric supercapacitor application

Highly stable 3D hierarchical manganese sulfide multi-layer nanoflakes with excellent electrochemical performances for supercapacitor electrodes

Transition metal sulfides are extensively studied as the watchful member of Faradic supercapacitive electrode materials because of their evidently enhanced electronic conductivity. Meanwhile, delicate development and manipulation of such novel nanostructured materials are required to achieve the desired electrochemical behaviors. Therefore, in this work a novel 3D hierarchical manganese sulfide (MS) multi-layer nanoflakes grown on Ni foam are designed and fabricated through the Kirkendall effect and applied as supercapacitors electrode. An advantage of such special 3D electrode architectures and unique compositional feature is in the fact that the as-prepared MS electrode presents greatly enhanced supercapacitive performances with ultrahigh specific capacity of 1.22 C cm−2 at 1 mV s−1 and fantastic cycling properties with the capacitance retention 100% after 1000 cycles. In addition, the electrochemical reaction of the MS electrode is a diffusion-controlled Faradaic redox process, while the diffusion coefficient is about 1.3 times larger than that of the manganese oxide (MO) electrode prepared under the same condition, suggesting the higher ion mobility of the MS electrode materials. These promising electrochemical behaviors demonstrate the great potential for application in high performance supercapacitors.

CTAB-templated formation of CuCo2O4/CuO nanorods and nanosheets for high-performance supercapacitor applications

CTAB-templated formation of CuCo2O4/CuO nanorods and nanosheets for high-performance supercapacitor applications

Oxygen-defect-rich 3D porous cobalt-gallium layered double hydroxide for high-performance supercapacitor application

In this work, oxygen-defect-rich, three-dimensional (3D) cobalt-gallium layered double hydroxides (Co0.50-Ga0.50-LDH) assembled by porous and ultrathin nanosheets are prepared by a simple one-step strategy. Briefly, an aqueous solution containing Co2+ and Ga3+ is quickly pouring into the aqueous solution of hexamethylenetetramine, the state-of-the-art LDH was obtained followed by a mild and fast hydrothermal reaction. This mild and rapid synthesis strategy introduces a large number of pores into the ultrathin LDH nanosheets, resulting in a high concentration of oxygen vacancies in the Co0.50-Ga0.50-LDH, and the concentration of oxygen vacancies can be arbitrarily modulated, which has been corroborated by X-ray photoelectron spectroscopy and electron spin resonance measurements. The synergistic effect of the oxygen vacancy and the introduced Ga ions in the LDH nanosheets enhances the adsorption of the LDH nanosheets on OH–, endowing Co0.50-Ga0.50-LDH with outstanding performance for the supercapacitor application. Co0.50-Ga0.50-LDH offers a high specific capacity (0.62C·cm−2) at 10 mV·s−1 and extraordinary cycling stability. An aqueous asymmetric supercapacitor (ASC) constructed with Co0.50-Ga0.50-LDH and activated carbon (AC) materials exhibits high energy density and a long lifespan. This result encourages the wide application of porous ultrathin LDH nanosheets in energy storage, catalysis and light response.

Coating activated carbon from coconut shells with Co3O4/CeO2 for high-performance supercapacitor applications: An experimental study

Activated carbon from coconut shells is a low-cost, environmentally friendly material that is available for fabricating the electrodes for electric double-layer capacitance supercapacitors. As such, activated carbon derived from coconut shells was coated with Co3O4/CeO2, and its electrical and ionic conductivity were evaluated. The ternary technique for selecting materials was systematically investigated with an economical process. The Co3O4/CeO2 coating that was formed on the activated carbon coconut shells was deemed AC-Co3O4-CeO2. The 90-05-05 composite was the best electrode for electric double-layer capacitance supercapacitors, resulting in high conductivity (0.62 x 103 S·cm2), low series resistance and internal resistance (based on the Nyquist plot), and the charge-discharge was able to reach 0.56 V for 90 seconds (1A/g). Therefore, activated carbon coconut shells coated in Co3O4/CeO2 can promote the necessary characteristics of electrodes needed for electric double-layer capacitance supercapacitors.

Polyindole intercalated graphitic carbon nitride (PIn/g-C3N4) composites for high-performance supercapacitor application

The polyindole/Graphitic carbon nitride (PIn/g-C3N4) composites synthesized by the reflux method. The characterization results showed that the composites possess balanced porosity, good charge diffusion, high energy and power densities. PIn/g-C3N4 composite showed the specific capacity (QS) of 440.8 C/g at 6 A/g in 1 mol/L aqueous H2SO4 electrolyte. The asymmetric device of PIn/g-C3N4//rGO showed QS of 73.84 C/g at 3 A/g. PIn/g-C3N4//rGO device offered a moderate cyclic retention of 72% at 18 A/g after 5,000 cycles with an energy density of 23.2 Wh/Kg and power density of 2307 W/Kg at 3 A/g. The results demonstrated that PIn/g-C3N4 composite has a potential application in field of energy storage devices.

Synthesis and electrochemical performance of porous FeCo2S4 nanorods as an electrode material for supercapacitor

FeCo2S4 nanorods structure grown onto nickel foam were formed by an easy hydrothermal process in this work. Initially, FeCo Lyared Double Hydroxides (FeCo LDH) nanosheets were realized via the hydrothermal technique. These sheets’ precursors were further converted into FeCO2O4 nanosheets by annealing. The FeCo LDH sheet's structure was converted into FeCo2S4 nanorods by a one-step sulfidation process. The results showed that the FeCo2S4 nanorod structure was successfully grown on Ni foam substrate. Electrochemically, the FeCo2S4 nanorods revealed a high specific capacitance of 4035 F g−1 at 1 A g−1 as a current density in 6 M KOH solution, with exceptional cycling stability of 80.4% capacitance retention and 100% coulombic efficiency after 5000 cycles. The FeCo2S4/NF// FeCo2S4/NF symmetric device gives the highest specific energy (37.72 W h kg−1) at the specific power (603.6 W kg−1) at current density 0.5 A g−1 beside exceptional cycling stability of 80.3% capacitance retention after 5000 charge/discharge cycles and excellent coulombic efficiency of 94%. The outstanding electrochemical characteristics of FeCo2S4 nanorods make them suitable candidate electrode materials for high-performance supercapacitors applications.

Construction of polypyrrole nanowires@cobalt phosphide nanoflakes core–shell heterogeneous nanostructures as high-performance electrodes for supercapacitors

• PPy@CoP CSHNs are synthesized using a two-step electrodeposition method. • PPy nanowires are wrapped by intercrossing CoP nanoflakes. • The PPy@CoP electrodes demonstrate enhanced rate capacities and cyclic stability. • Unique structural advantages account for the improved energy storage performance. In this reported work, polypyrrole (PPy)@cobalt phosphide (CoP) core–shell heterogeneous nanostructures (CSHNs) are grown directly on the Ni foam using a two-step electrochemical synthesis method. The morphology and microstructure analysis reveal that PPy nanowires are uniformly wrapped by intercrossing CoP nanoflakes, which endows the CSHNs with abundant electroactive sites, high electrical conductivity, and good structural stability. Electrochemical studies show that the PPy@CoP CSHNs as supercapacitor (SC) electrodes demonstrate a higher specific capacity (443C g −1 at 1 A g −1 ) and better cycling performance (93% initial capacity retention after 5000 cycles at 5 A g −1 ) than the pure PPy and CoP electrodes. Besides, a hybrid supercapcitor (HSC) device with the PPy@CoP positive electrode yields a high energy density of 38.1 Wh kg −1 at a power density of 750 W kg −1 . This work offer a new insight into the rational design of the heterostructures based on PPy and metal phosphides for application in high-performance SCs.

Development, Investigation, and Comparative Study of the Effects of Various Metal Oxides on Optical Electrochemical Properties Using a Doped PANI Matrix.

A comparative study was performed in order to analyze the effect of metal oxide (MO) on the properties of a polymeric matrix. In this study, polyaniline (PANI)@Al2O3, PANI@TiC, and PANI@TiO2 nanocomposites were synthesized using in situ polymerization with ammonium persulfate as an oxidant. The prepared materials were characterized by various analytical methods such as X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV/visible (UV/Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Furthermore, the conductive properties of the materials were tested using the four-point probe method. The presence of MO in the final product was confirmed by XPS, XRD, FTIR, and TEM, while spectroscopic characterization revealed interactions between the MOs and PANI. The results showed that the thermal stability was improved when the MO was incorporated into the polymeric matrix. Moreover, the results revealed that incorporating TiO2 into the PANI matrix improves the optical bandgap of the nanocomposite and decreases electrical conductivity compared to other conducting materials. Furthermore, the electrochemical properties of the hybrid nanocomposites were tested by cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD). The obtained results suggest that the PANI@TiO2 nanocomposite could be a promising electrode material candidate for high-performance supercapacitor applications.

Synthesis of bimetallic MoS2/VS2 nano-urchins-reduced graphene oxide hybrid nanocomposite for high performance supercapacitor application

Two-dimensional (2-D) structure and high conductivity of the metal disulphides (MDs) are interesting for the applications in the energy storage sector. Nevertheless, their high instability restricts their widespread applications. In this work, we report MoS2/VS2 nano-urchins homogeneously grown onto reduced graphene oxide (rGO) matrix (denoted as G-MVS) via a facile hydrothermal approach and its electrochemical performance in an aqueous electrolyte system. G-MVS has a high specific capacitance of 460 F g−1 (287.5 F cm−2) at 0.5 A g−1 and 310 F g−1 (193.75 F cm−2) at 10 A g−1. In a symmetric configuration G-MVS//G-MVS, a high energy density of 49 Wh kg−1 (67.86 mWh cm−2) at a power density of 700.25 W kg−1 was achieved.

Green synthesis of ZnO and CuO NPs using Ficus benghalensis leaf extract and their comparative study for electrode materials for high performance supercapacitor application

In this paper, we present green synthesis of zinc oxide (ZnO) nanoparticle (NPs) and copper oxide (CuO) NPs using leaf extract of Ficus benghalensis (banyan tree) and their study for high performance supercapacitor application. Herein, we have used 1 mL freshly prepared leaf extract of Ficus benghalensis as capping/stabilizing agent for the synthesis of ZnO and CuO NPs. These synthesized NPs have been characterized by using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), powder X-ray diffraction (PXRD) and fourier transform infrared spectroscopy (FTIR). The SEM images of ZnO and CuO NPs show morphology of both the nanoparticles. The EDS, FT-IR and XRD data are used for the structural characterization of nanoparticles. The presence of phytochemicals (organic compounds) at the surface of nanoparticles confirms their capping/stabilizing role in the synthesis of the nanoparticles. The cyclic voltammetry (CV) study has been done for getting specific capacitance (Cs) for supercapacitor application. The obtained values of specific capacitance (Cs) for ZnO NPs are 6.318 F g−1 at 20 mV/s, 4.363 F g−1 at 40 mV/s , 3.611 F g−1 at 60 mV/s, 3.222 F g−1 at 80 mV/s and 2.972 F g−1 at 100 mV/s respectively. In the same manner, the obtained values of specific capacitance for CuO NPs are 2.144 F g−1 at 20 mV/s, 1.916 F g−1 at 40 mV/s, 1.846 F g−1 at 60 mV/s, 1.775 F g−1 at 80 mV/s and 1.725 F g−1 at 100 mV/s respectively. The values of energy density have been calculated for both ZnO NPs and CuO NPs. The calculated values of energy density for ZnO NPs at the abovementioned scan rates are 1.0620 Wh/kg, 0.7334 Wh/kg, 0.6070 Wh/kg, 0.5416 Wh/kg and 0.4996 Wh/kg respectively. Similarly, the calculated values of energy density for CuO NPs are found to be.0.1904 Wh/kg, 0.1701 Wh/kg, 0.1639 Wh/kg, 0.1576 Wh/kg, and 0.1532 Wh/kg respectively.

Free-standing 3D Co3O4@NF micro-flowers composed of porous ultra-long nanowires as an advanced cathode material for supercapacitor

The development of smart structured cathode materials for supercapacitors (SCs) has sparked tremendous interest. However, the appropriate design to achieve high capacitance and energy density-based cathode materials remains a major problem for energy storage systems. This article describes the effective synthesis of self-supported 3D micro-flowers composed of ultrathin nanowires array of Co3O4 on Ni foam (NF) using hydrothermal conditions (Co3O4@NF). The mesoporous Co3O4@NF with a high surface area, providing a rich active state for the Faraday redox reaction and increasing the diffusion rate of the electrolyte ions. The optimized Co3O4@NF-16h electrode exhibited supreme electrochemical performance by delivering a high specific capacitance of 1878, (1127) and 1200 (720 C g−1) F g−1 at 1.0 and 20 A g−1, respectively. The Co3O4@NF electrode retained good capacitance stability of 91% over 10000 cycles at 20 A g−1 with excellent rate-performance of 67% at 20 folded high current values. The obtained results for the Co3O4@NF electrode are presented the enhanced pseudocapacitive performance, indicating the substantial potential for high-performance supercapacitor applications.

Crafting nanoflower-built MnCo2S4 anchored to Ni foam as a prominent energy conversion and energy storage electrode for high-performance supercapacitor applications

Ternary compound for engineering nanoarchitecture of MnCo2S4 has been hierarchically well maintained and attractive surface area was regarded as a potentially efficient technique to grow novel electroactive materials. In this regard, crafting Nano flower-built MnCo2S4 nanoarchitecture with Ni foam network favors short path roots and interconnected for excellent charging transfer and ion transmission, which allows the energetic Faradaic redox procedures by the improves active surface. According to the structural and compositional features, the as-developed MnCo2S4 nanoflower nanoarchitecture exhibits superior electrochemical capacity activities. Impressively, the MnCo2S4 nanoflowers achieve an excellent specific capacitance of 779 F g−1 at a current density of 1 A g−1, which causes unique features of structural construction. When tested long-term cycling stability performance, the as-constructed MnCo2S4 nanoflowers achieves excellent capacitance retention 96.5% over 3000 cycling stability performance at a current density of 2 A g−1 with superior conductivity. Considered the above points, the simplistic approach yet unique construction of this MnCo2S4 holds substantial potential energy conversion and high-performance energy storage.

Facile Preparation and Performances of Ni, Co, and Al Layered Double Hydroxides for Application in High-Performance Asymmetric Supercapacitors

Facile Preparation and Performances of Ni, Co, and Al Layered Double Hydroxides for Application in High-Performance Asymmetric Supercapacitors

Silver Nanoparticles Embedded on Reduced Graphene Oxide@Copper Oxide Nanocomposite for High Performance Supercapacitor Applications.

In this work, silver (Ag) decorated reduced graphene oxide (rGO) coated with ultrafine CuO nanosheets (Ag-rGO@CuO) was prepared by the combination of a microwave-assisted hydrothermal route and a chemical methodology. The prepared Ag-rGO@CuO was characterized for its morphological features by field emission scanning electron microscopy and transmission electron microscopy while the structural characterization was performed by X-ray diffraction and Raman spectroscopy. Energy-dispersive X-ray analysis was undertaken to confirm the elemental composition. The electrochemical performance of prepared samples was studied by cyclic voltammetry and galvanostatic charge-discharge in a 2M KOH electrolyte solution. The CuO nanosheets provided excellent electrical conductivity and the rGO sheets provided a large surface area with good mesoporosity that increases electron and ion mobility during the redox process. Furthermore, the highly conductive Ag nanoparticles upon the rGO@CuO surface further enhanced electrochemical performance by providing extra channels for charge conduction. The ternary Ag-rGO@CuO nanocomposite shows a very high specific capacitance of 612.5 to 210 Fg−1 compared against rGO@CuO which has a specific capacitance of 375 to 87.5 Fg−1 and the CuO nanosheets with a specific capacitance of 113.75 to 87.5 Fg−1 at current densities 0.5 and 7 Ag−1, respectively.

“Mn” Incorporated Coconut Water Derived Carbon for Supercapacitor Application

Carbon derived from natural precursors is attracting tremendous attention from the scientific community for high-performance supercapacitor applications. This is for the first time; one-step synthesis was carried out for Mn incorporated carbon derived from coconut water as the starting precursor via the spray pyrolysis method. An energy-efficient, low-cost, and eco-friendly method of synthesis is a need of time. Three different concentrations (0.08 M, 0.05 M, and 0.02 M) of “Mn” incorporated carbon were prepared and tested for supercapacitor application. Among these, 0.05 M Mn incorporated coconut water carbon (Mn/CWC) manifests the highest areal capacitance of 438.33 mF cm−2 at the current density of 2 mA cm−2 with the energy density of 21.91 × 10−3 Wh cm−2 and 299.9.18 × 10−3 W cm−2 power density and shown 94.8% of capacitance retention rate at the current density of 4 mA cm−2 after the 2000 cycles. The results indicated that 0.05 M Mn incorporated CWC can be a potential candidate for electrode material in energy storage applications.

Rational design of porous NiCo2S4 nanotubes for hybrid supercapacitor

The nanotube-consisted flower-like NiCo2S4 is successfully fabricated by a novel two-step hydrothermal technique. X-ray diffraction (XRD) identifies the spinel structure, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) imply the flower-like morphology of the synthesized NiCo2S4. The electrochemical behaviors are studied by cyclic voltammetry and galvanostatic charge-discharge measurements. The NiCo2S4 nanotubes demonstrate enhanced pseudocapacitive performance of 429.5 C g−1 at current density of 0.5 A g−1. The NiCo2S4//AC device delivers high energy density of 37.69 Wh kg−1, maximum power density of 4000.6 W kg−1 and satisfied cycle property of 96% capacitance retention after over 7000 cycles. The results show that the NiCo2S4 nanotubes are promising electrode material for high performance supercapacitor applications.

In-situ sputtered 2D-MoS2 nanoworms reinforced with molybdenum nitride towards enhanced Na-ion based supercapacitive electrodes

We report the fabrication of binder-free, low-cost and efficient hybrid supercapacitive electrode based on the hexagonal phase of two-dimensional MoS2 nanoworms reinforced with molybdenum nitride nanoflakes deposited on stainless steel (SS) substrate using reactive magnetron sputtering technique. The hybrid nanostructured MoS2–Mo2N/SS thin film working electrode delivers a high gravimetric capacitance (351.62 F g−1 at 0.25 mA cm−2) investigated in 1 M Na2SO4 aqueous solution. The physisorption/intercalation of sodium (Na+) ions in electroactive sites of MoS2–Mo2N composite ensures remarkable electrochemical performance. The deposited porous nanostructure with good electrical conductivity and better adhesion with the current collector demonstrates a high-energy density of 82.53 Wh kg−1 in addition to a high-power density of 24.98 kW kg−1. Further, excellent capacitance retention of 93.62% after 4000 galvanostatic charge–discharge cycles elucidated it as a promising candidate for realizing high-performance supercapacitor applications.

Controllable synthesis of the polymorphic porous carbon with N-doping/Ni magnetic nanohybrids for high performance supercapacitor and environment applications

Porous carbon with heteroatom-doping/metal nanohybrids are of specific interest for many promising applications such as supercapacitors and pollutants removal, while their controllable synthesis is still a considerable challenge. Herein, we report a kind of novel polymorphic porous carbon with N-doping/Ni magnetic nanohybrids (NC@Ni), which can be fabricated via a simple self-jet vapor-phase growth assisted strategy, and the microstructure of the NC@Ni nanohybrids can be facilely controlled through adjusting the stoichiometric ratio of the precursors nickel nitrate hexahydrate and lactose monohydrate. Characterization results show that the fabricated NC@Ni nanohybrids own large specific surface area, ultrahigh nitrogen and oxygen doping content, abundant pore structure and attractive saturation magnetization. When used as supercapacitor electrode material, the typical NC@Ni-1 electrode exhibited an attractive specific capacity of 590C g−1 at 1 A g−1, remarkable rate performance (74.5%, 1–20 A g−1), and excellent cycling stability. Meanwhile, the assembled asymmetric supercapacitor delivered an excellent energy density up to 75.1 Wh kg−1 at a power density of 1055 W kg−1. As an adsorbent, the typical product NC@Ni-0.75 displayed high capture capability towards MG dye (889 mg g−1) and phosphate (26.2 mg P g−1) at 25 OC.

Self-Doped Activated Carbons from Car Exhaust as High-Performance Supercapacitor Electrode Materials for Sustainable Energy Storage System

Hydrocarbon based waste materials are emerging as an attractive source of generating activated carbons (ACs), having excellent potential for enormous in-field applications. In this study, it has been demonstrated that the carbon materials collected from the diesel engine exhaust could be a new source for preparing self-doped highly porous AC for high-performance supercapacitor applications. As the diesel engine exhaust carbon (DEEC) itself contains a large number of heteroatoms (O, N, S, and P), simple acid treatment (HCl) of DEEC resulted in a self-doped AC (SDAC_HCl) having contained a high level of heteroatoms as the dopant in it and consequently provided with a large specific surface area of 89 m2g−1. The pyrolytic treatment of DEEC with KOH further resulted in self-doped AC (SDAC_KOH) with an enhanced specific surface area of 549 m2g−1 due to the increase in porosity of AC. The supercapacitor performance of the AC materials is evaluated in a symmetric two-electrode cell. The ACs (SDAC_HCl and SDAC_KOH) have shown very high specific capacitance (C sp) with aqueous (sodium sulfate, Na2SO4), organic (tetraethylammonium tetrafluoroborate/acetonitrile, TEABF4/AN) and ionic liquid (1-butyl-3-methylimidazolium chloride, [BMIM][Cl]) electrolytes. The highest C sp of 403 Fg−1 at the current density of 1 Ag−1 is obtained in SDAC_KOH with [BMIM][Cl] electrolyte. The C sp is 193 F g−1 at the high current density of 10 Ag−1, demonstrating the good compatibility of the electrolyte with the electrode material. The SDAC_KOH with [BMIM][Cl] is able to supply a high energy density of 35.8 Whkg−1 at a power density of 400 Wkg−1 which is very reasonably high compared to other reported AC materials. The SDAC_KOH has shown excellent stability in continuous galvanostatic charge-discharge cycles. The SDAC_KOH has retained 98% of its initial capacitance after 10000 cycles at a high current density of 5 Ag−1. The facile and effective strategies employed in this study in developing high-performance supercapacitor electrode materials from waste may help design and develop sustainable energy storage systems.