High-performance Supercapacitor Applications Research Articles

CuFeS2/Carbon Sphere Nanocomposites for Improved Capacitive Performance

CuFeS2 has many advantages, like high electrical conductivity, multiple redox centers, natural abundance and nontoxic. However, the low capacitance limits their application. In this work, we use carbon spheres (CS) prepared from starch to modify CuFeS2. The prepared CuFeS2/CS shows special structures with the CS as the core and CuFeS2 as the shell. These CuFeS2/CS nanocomposites show improved capacitive performance. CuFeS2/CS has a specific capacitance of 349.4[Formula: see text]F[Formula: see text]g[Formula: see text] at 0.5[Formula: see text]A[Formula: see text]g[Formula: see text], four times that of pristine CuFeS2 (88.8[Formula: see text]F[Formula: see text]g[Formula: see text], which might be attributed to the increased electrolyte diffusion capacity. The cyclic stability is also slightly improved, from 86.4% of the pristine CuFeS2 to 90.5% of the CuFeS2/CS nanocomposites due to the rigid structure of both crystal CuFeS2 and firm CS. These CuFeS2/CS nanocomposites are expected to be used in high-performance supercapacitor applications.

An in-depth investigation of physico-electro chemical properties of NiCo2S4 nano composites for high-performance supercapacitor applications

An in-depth investigation of physico-electro chemical properties of NiCo2S4 nano composites for high-performance supercapacitor applications

An in-depth investigation of physico-electro chemical properties of NiCo2S4 nano composites for high-performance supercapacitor applications

An in-depth investigation of physico-electro chemical properties of NiCo2S4 nano composites for high-performance supercapacitor applications

Electrical conductivity of polyvinyl alcohol/carboxymethyl cellulose doped by zinc oxide and hematite nanoparticles for optoelectronics devices

This research explores polymer nanodielectrics, a category of materials where nanoceramic fillers are incorporated into polymers. These hybrid materials are gaining significant interest due to their tunable optical and electrical properties, making them potentially well-suited for applications in flexible optoelectronic and organic electronic devices. Polyvinyl alcohol (PVA), Carboxymethyl cellulose (CMC), zinc oxide (ZnO), and hematite (Fe2O3) nanoparticles (NPs) have been used to create nanocomposite materials in order to improve their optical and electrical characterization. Physical methods have been used to investigate the effects of varying hematite nanoparticle contents on the optical and electrical characterization of the prepared films. XRD analysis indicated a reduction in the crystalline character of the PVA/CMC blend following the incorporation of ZnO/Fe2O3 nanoparticles (NPs). FTIR data approved the interaction between the PVA/CMC composite and the ZnO/Fe2O3, leading to a decrease in intermolecular interactions within the polymeric matrix and coordination with the ZnO/Fe2O3. Electrical analysis obtained an enhancement in σac values with the rise of ZnO/Fe2O3 NPs content up to 30 min of laser ablation times in the polymeric nanocomposite due to the high content of ZnO/Fe2O3 NPs that were added to the PVA/CMC hybrid polymer matrix. The findings from this study suggest the promise of these materials for applications in high-performance batteries, supercapacitors, or other next-generation energy storage and conversion devices.

Enhanced electrochemical characteristics of Mn$$-$$Al-co-doped SnO2 nanostructures for high-performance supercapacitor application

Enhanced electrochemical characteristics of Mn$$-$$Al-co-doped SnO2 nanostructures for high-performance supercapacitor application

Utilization of shea butter waste-derived hierarchical activated carbon for high-performance supercapacitor applications

Utilization of shea butter waste-derived hierarchical activated carbon for high-performance supercapacitor applications

Study on the electrochemical performance of Ni-doped ZnO nanorods utilized for the high-performance supercapacitor application

Study on the electrochemical performance of Ni-doped ZnO nanorods utilized for the high-performance supercapacitor application

Tuning the water interlayer spacer of microwave-synthesized holey graphene films towards high performance supercapacitor application

Abstract Graphene-based electrodes have been extensively investigated for supercapacitor applications. However, their ion diffusion efficiency is often hindered by the graphene restacking phenomenon. Even though holey graphene (hG) is fabricated to address this issue by providing ion transport channels, those channels could still be blocked by densely stacked graphene nanosheets. To tackle this challenge, this research aims at improving the ion diffusion efficiency of microwave-synthesized hG films by tuning the water interlayer spacer towards the improved supercapacitor performance. By controlling the vacuum filtration during graphene-based electrode fabrication, we obtain dry films with dense packing and wet films with sparse packing. The SEM images reveal that 20 times larger interlayer distance is constructed in the wet film compared to that in the dry counterpart. The hG wet film delivers a specific capacitance of 239 F g−1, ∼82% enhancement over the dry film (131 F g−1). By an integrated experimental and computational study, we quantitatively show that the interlayer spacing in combination with the nanoholes in the basal plane dominates the ion diffusion rate in hG-based electrodes. Our study concludes that novel hierarchical structures should be further considered even in hG thin films to fully exploit the superior advantages of graphene-based supercapacitors.

Time-dependent synthesis of tungsten disulfide for flexible supercapacitors

Tungsten disulfide (WS2) with various nanostructures was synthesized for times ranging from 6 to 72 h, using a simple and easy hydrothermal technique, for high-performance supercapacitor applications. The synthesized WS2 for 24 h (WS2–24), among other synthesized WS2, exhibited flower-like structures, composed of numerous nanosheets, demonstrating superior electrochemical properties in terms of electrochemical surface area, charge transfer resistance, specific capacitance, and rate capability. In addition, WS2–24 was coated on a flexible activated carbon cloth substrate to make flexible electrodes and assemble a flexible symmetric supercapacitor with a gel electrolyte. The flexible supercapacitor exhibited a specific capacitance of 262.5 F g−1 at 1 A g−1 with an energy density of 23.6 Wh kg−1 and a power density of 802 W kg−1. It also showed excellent capacitance retention of 94.5 % and a Coulombic efficiency of 86.4 % after 5000 cycles. The remarkable electrochemical properties of the synthesized WS2 materials highlight them as highly effective active materials for high-performance supercapacitor electrodes.

Boosting the electrochemical properties of MoO3/MnFe2O4/MXene for high-performance supercapacitor applications

The expanding population and extensive usage of energy-consuming sources are the main factors driving the interest of current researchers toward the development of extremely effective and useful electrode materials for high-power energy storage devices. A novel class of 2D transition metal carbides such as MXene has captured significant attention and has distinguished itself from other electrode materials because of its remarkable electrochemical characteristics. In this work, we have fabricated MoO3 and MnFe2O4 via a simple co-precipitation method. Further, we design multifunctional MoO3/MnFe2O4/MXene composite by the combination of MoO3/MnFe2O4 and MXene through the sonication route. SEM results confirmed the fabrication of nanorods of MoO3 and nanoparticles of MnFe2O4, sandwiched within the MXene sheets. As evident from CV profiles, at 10 mVs−1 MoO3/MnFe2O4@MXene showed a higher specific capacitance of 817 Fg−1 than other electrode materials mainly because of the combined effect of MoO3/MnFe2O4 and the conductive nature of MXene sheets. Furthermore, even after 10,000 cycles, MoO3/MnFe2O4/MXene demonstrated outstanding cyclic stability, maintaining 90.2 % retention of its initial specific capacitance. Furthermore, MoO3/MnFe2O4/MXene showed less solution resistance and charge transfer resistance than all other prepared materials. These findings suggest that the MoO3/MnFe2O4/MXene composite is a competent capacitive material in the supercapacitor research area.

Ultrasonic-Assisted Electrodeposition of Mn-Doped NiCo2O4 for Enhanced Photodegradation of Methyl Red, Hydrogen Production, and Supercapacitor Applications

This paper presents a novel ultrasonic-assisted electrodeposition process of Mn-doped NiCo2O4 onto a commercial nickel foam in a neutral electroplating bath (pH = 7.0) under an ultrasonic power of 1.2 V and 100 W. Different sample properties were studied based on their crystallinity through X-ray diffraction (XRD), morphology was studied through scanning electron microscopy (SEM), and photodegradation was studied through ultraviolet–visible (UV–Vis) spectrophotometry. Based on the XRD results, the dominant crystallite phase obtained was shown to be a pure single NiCo2O4 phase. The optical properties of the photocatalytic film showed a range of energy band gaps between 1.72 and 1.73 eV from the absorption spectrum. The surface hydroxyl groups on the catalytic surface of the Mn-doped NiCo2O4 thin films showed significant improvements in removing methyl red via photodegradation, achieving 88% degradation in 60 min, which was approximately 1.6 times higher than that of pure NiCo2O4 thin films. The maximum hydrogen rate of the composite films under 100 mW/cm2 illumination was 38 μmol/cm2 with a +3.5 V external potential. The electrochemical performance test also showed a high capacity retention rate (96% after 5000 charge–discharge cycles), high capacity (260 Fg−1), and low intrinsic resistance (0.8 Ω). This work concludes that the Mn-doped NiCo2O4 hybrid with oxygen-poor conditions (oxygen vacancies) is a promising composite electrode candidate for methyl red removal, hydrogen evolution, and high-performance hybrid supercapacitor applications.

Nitrogen and oxygen self-doped hierarchical porous carbon nanosheets derived from turmeric leaves for high-performance supercapacitor

It is a formidable challenge to develop efficient and low-cost nanostructured carbonaceous materials for electrochemical energy storage application. Herein, a hierarchical porous carbon nanosheet is successfully synthesized in a facile manner from turmeric leaves by a two-step chemical activation strategy using KOH activator. The biomass-derived interconnected two-dimensional (2D) carbon framework prepared at 900 °C presents high self-doped N (11.42 at%) and O contents (7.77 at%) together with specific surface area and pore volume of 541 m2/g and 0.47 cm3 g−1, respectively. Consequently, the resultant electroactive functional material shows a specific capacitance of 389 and 310 F/g at a current density of 1 A/g in acidic and neutral electrolytes, respectively. Additionally, an assembled symmetric supercapacitor device in Na2SO4 electrolyte delivers good capacitance retention of 90 % after 5000 consecutive charge–discharge cycles along with high specific energy (39.44 Wh kg−1at specific power of 0.49 kW kg−1). This work provides a cost-effective, eco-friendly and sustainable outlook to prepare high-valued porous carbons from reliable biomass sources for high-performance supercapacitor application.

NiCo2O4@SnS2 nanosheets on carbon cloth as efficient bi-functional material for high performance supercapacitor and sensor applications

Bi-functional materials provide an opportunity for the development of high-performance devices. Up till now, bi-functional performance of NiCo2O4@SnS2 nanosheets is rarely investigated. In this work, NiCo2O4@SnS2 nanosheets were synthesized on carbon cloth by utilizing a simple hydrothermal technique. The developed electrode (NiCo2O4@SnS2/CC) was investigated for the detection of L-Cysteine and supercapacitors applications. As a non-enzymatic sensor, the electrode proved to be highly sensitive for the detection of L-cysteine. The electrode exhibits a reproducible sensitivity of 4645.82 μA mM−1 cm−2 in a wide linear range from 0.5 to 5 mM with a low limit of detection (0.005 μM). Moreover, the electrode shows an excellent selectivity and long-time stability. The high specific surface area, enhanced kinetics, good synergy and distinct architecture of NiCo2O4@SnS2 nanosheets produce a large number of active sites with substantial energy storage potential. As a supercapacitor, the electrode exhibits improve capacitance of 655.7 F g−1 at a current density of 2 A g−1 as compare to NiCo2O4/CC (560 F g−1). Moreover, the electrode achieves 95.3% of its preliminary capacitance after 10 000 cycles at 2 A g−1. Our results show that NiCo2O4@SnS2/CC nanosheets possess binary features could be attractive electrode material for the development of non-enzymatic biosensors as well as supercapacitors.

Hydrothermal synthesis of nickel vanadate (Ni2V2O7) microspheres as a catalyst for high-performance supercapacitor and water-splitting applications

In this work, the hydrothermal method was employed to synthesize the nickel vanadate microspheres (NVO MSs), an effective catalyst for supercapacitor and water-splitting applications. Specifically, X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, and Brunauer-Emmett-Teller (BET) were used to examine the crystal structure, surface morphology, functional group identification, the stretching-bending vibration of the N–V–O group, and the specific surface area respectively. Additionally, this paper reports the electrochemical aspects of NVO MSs in various concentrations of KOH electrolyte using nickel foam (NF) as a current collector. As a result, the NVO-NF 1 electrode exhibited excellent electrochemical activity with a higher specific capacitance (Cs) and capacity (Csp) of 959 F/g and 119 mAh/g at a current density of 5 mA/g respectively. Moreover, the NVO-NF 1 electrode delivers maximum energy (Ed) and power density (Pd) of 26 Wh/kg and 1100 W/kg and excellent stability with 90 % retention after 4000 CV cycles. In the asymmetric liquid state device (ASC), the NVO-NF acts as a cathode, and activated carbon (AC) as a anode materials respectively. Furthermore, the fabricated ASC device reveals maximum Ed and Pd of 47 Wh/kg and 2300 W/kg at 5 mA/g and also demonstrated superior stability over 5000 cycles. Furthermore, the significant finding of the NVO-NF 1 electrodes reveals superior electrocatalytic activities such as the lowest value of overpotential (234 mV), with the sufficient Tafel slope (73 mV/dec), as well as the maximum electrochemical active surface area (670.5 cm2) in 1 M KOH at 10 mA/cm2 respectively. As a result, better performance of the NVO-based MSs in 1 M KOH electrolyte was effectively applied to power effective electrodes for energy storage and water-splitting.

Nilgiri tree peels-derived activated porous carbon for high performance supercapacitor applications

In this study, the activated porous carbon (APC-x) was collected from Nilgiri tree peels, making it a sustainable and cost-effective green synthesis approach. The raw material undergoes carbonization and activating it using KOH as chemical activation agent. The chemical composition, crystallinity and morphology of the surface of ACP-x was examined by Fourier Transform infra-red (FTIR), X-ray diffraction and Field emission scanning electron microscope (FESEM). The cyclic voltammetry technique was used to measure the electrochemical performance of APC-x using PVA/KOH gel electrolyte in two-electrode system. The highest specific capacitance value 140 F/g was obtained for APC-0 at scan rate of 10 mV/s. The use of Nilgiri tree peels as precursor for activated porous carbon production presents a sustainable approach for developing high-performance supercapacitor materials.

Utilizing bamboo shoot shells to develop hierarchical porous carbon materials for high–performance supercapacitor applications

Hierarchical porous carbon materials were synthesized from bamboo shoot shells via KOH activation. The physicochemical properties of bamboo shoot shell–based hierarchical porous carbon (BBCK) were investigated by scanning electron microscopy, X–ray diffraction, Raman spectroscopy, X–ray photoelectron spectroscopy, and N2 adsorption–desorption analyses. Results confirmed that the ratio of KOH to BBCK significantly affected the pore structure, O content and electrochemical properties of BBCK. The obtained BBCK exhibited a specific surface area of 1394 m2 g–1 and a pore volume of 0.58 cm3 g–1. The O content of BBCK was 25.09%. The formation mechanism of BBCK, which had a hierarchical porous structure via KOH activation, was illustrated systematically. The specific capacitance was 320.05 F g–1 at 0.5 A g–1 in the 6 M KOH electrolyte, and multiplicity performance was 75.22% at 10 A g–1. The assembled symmetric supercapacitors demonstrate the power density was 250 W kg–1, and the energy density was 7.36 Wh kg–1. After 7000 cycles, the capacitance retention rate at 100%.

Waste polyethylene terephthalate plastic derived Zn-MOF for high performance supercapacitor application

A simple chemical approach was used to prepare Zn-MOF or MOF-5 derived from polyethylene terephthalate bottles for supercapacitor applications. The morphology, and structure of PET-derived MOFs were characterized using various techniques, including scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermogravimetric analysis, fourier transform infrared spectroscopy, and BET surface area and nitrogen adsorption/desorption analysis. The BET surface area of MOF-5 was determined to be 88 m2g−1 and N2 adsorption–desorption analysis, showed the type-IV isotherms and suggest the existence of capillary condensation within the meso- and micropore structures. An excellent specific capacitance ranging from 341 to 191 F g−1 recorded form the scan rate of 2–200 mV s−1 by CV for Zn-MOF. Moreover, the highest specific capacitance 353 F g−1 calculated at 0.5 A/g current density. The highest value of specific capacitance Cs 353 F g−1 was found for lowest current density of 0.5 A/g. An excellent cyclic stability was obtained after running 2000 cyclic runs at a scan rate of 50 mV s−1. The small semicircle of EIS plot exhibits superior electrochemical performance of the Zn-MOF. The waste PET plastic derived Zn-MOF showed an excellent supercapacitor performance which can be utilized in energy storage applications. This approach not only facilitates environmental remediation but also offers a valuable organic linker for energy material synthesis.

One-pot synthesis of phosphorous, iodine atoms co-functionalized graphene for high-performance supercapacitor and flame-retardant applications

There has been extensive research on heteroatom-doped graphene for electrochemical energy storage and flame-retardant (FR) applications. Herein, we used a one-pot method for developing phosphorous, iodine co-doped reduced graphene oxide (PI@rGO) from red phosphorus and iodine via in situ graphene oxide (GO) reduction for supercapacitor and FR applications. In a symmetrical two-electrode cell device, the as-prepared PI@rGO demonstrated good super capacitive performance of 178 F g−1 at a current density of 1.0 A g−1, along with an exceptional energy density of 20 Wh kg−1 and power density of 1791 W kg−1. The as-synthesized PI@rGO demonstrated outstanding cyclic stability at a high current density of 10 A g−1, retaining up to 84 % of its initial capacitance after more than 6000 recurrent charge–discharge cycles. The synthesized PI@rGO showed excellent FR properties toward cotton fabric and sustained cotton fabric up to 337 s with continuous flame exposure. The control cotton fabric was completely burned in 16 s. The synthesized PI@rGO coated cotton fabric showed an excellent value of 39 % limiting oxygen index and residual char length of 2 cm. With the excellent super capacitive performance and FR properties, PI@rGO can be a promising candidate for different applications including supercapacitors and FR products.

Porous α-Fe2O3 Hollow Rods/Reduced Graphene Oxide Composites Templated by MoO3 Nanobelts for High-Performance Supercapacitor Applications.

Porous α-Fe2O3 hollow rods/reduced graphene oxide (α-Fe2O3 HR/RGO) composites with unique morphological characteristics and a high surface area are prepared through a template strategy, which was systematically studied and found to have outstanding supercapacitive properties. When served as active material in a three-electrode setup, the optimized α-Fe2O3 HR/RGO-30, comprised 76.5 wt% α-Fe2O3 and 23.2 wt% RGO, was able to offer the largest specific capacitance of 426.3 F g-1, an excellent rate capability as well as satisfactory cycle life with capacitance retention of 87.7% and Coulombic efficiency of 98.9% after continuously charging/discharging at 10 A g-1 for beyond 10,000 cycles. Such electrochemical behaviors of the α-Fe2O3 HR/RGO-30 electrode can rival or even surpass those of many Fe2O3-based electrodes documented in the previous literature. Later, a symmetric supercapacitor cell of α-Fe2O3 HR/RGO-30//α-Fe2O3 HR/RGO-30 was fabricated. The assembled device offers the maximum energy density of 18.7 Wh kg-1, and also exhibits commendable rate capability, and features stable cycling durability (with capacitance retention of 83.2% together with a Coulombic efficiency of 99.3% after 10,000-cycle charge/discharge at 5 A g-1). These notable electrochemical performances enable the α-Fe2O3 HR/RGO-30 composite to be a high-potential material for advanced energy storage systems.

ReS2/CoS heterostructure catalysts for electrochemical application in hydrogen evolution and supercapacitor

Development of Nano-heterostructures based on transition metal chalcogenides is promising strategy to accelerate the catalytic performance for hydrogen evolution reaction (HER) and supercapacitor application. The design and development of non-noble transition metal based catalysts is required for the low-cost, efficient and earth-abundant electrodes for sustainable energy conversion and storage. ReS2/CoS heterostructures were synthesized by two step methods involving liquid phase exfoliation of ReS2 and hydrothermal decoration of CoS. The prepared ReS2/CoS heterostructures shows high performance supercapacitor applications with specific capacitance of 663.2 F/g at 2 A/g and 643.1 F/g at scan rate 5 mV/s, showing enhanced redox reaction and number of electrochemically active sites due to synergistic effect and modulated electronic structure. Additionally, ReS2/CoS heterostructures shows the superior HER performance in alkaline condition with overpotential of 187 mV at 10 mA/cm2 due to accelerated kinetics, enhanced ECSA and low charge transfer resistance. The ReS2/CoS heterostructures shows the stable electrochemical performance for HER for more than 17 h.