Electrode Material For Supercapacitor Applications Research Articles

Pseudocapacitive behaviors of strontium-doped cobalt ferrite nanoparticles for supercapacitor applications

Metal oxides are widely used as electrode materials due to their high potential for various applications. Specifically, spinel-structured cobalt ferrite is employed in various energy applications. Among the available conventional techniques to synthesize nano-ferrites, the sol-gel combustion approach is one of the simplest and most effective. In this work, strontium-doped cobalt ferrite nanoparticles are synthesized using the sol-gel combustion technique and annealed at various temperatures. Further, the prepared samples are characterized using XRD to identify the phase and crystallinity of the materials. It shows the average crystallite sizes of 33, 36, and 35 nm for various temperatures of 200 °C, 300 °C, and 500 °C, respectively. FESEM illustrated the clustered and homogeneous structure of the sample. From UV-Vis-NIR absorption spectroscopy, direct bandgap energy values are calculated using Tauc’s plot as 1.24, 1.21, and 1.20 eV. To examine electrochemical properties, galvanostatic measurements are used. The observed sample (Co0.8Sr0.2Fe2O4 at 300 °C) shows a supercapacitance value of 637 Fg−1 at 0.5 Ag−1 and retained 85.5 % after 1000 cycles at 5 Ag−1, showing 98.79 % coulombic efficiency after 5000 cycles at 15 Ag−1. The result indicates that doped nanoferrites are a promising electrode material for supercapacitor applications.

Insight into use of biopolymer in hybrid electrode materials for supercapacitor applications—A critical review

The shortage of natural resources due to the progression of the human population and environmental pollution has become crucial concern topics to resolve. One of the best ways to resolve this is to develop renewable energy-based storage systems. Supercapacitors are emerging as promising storage systems via providing rapid charging/discharging and high power delivery, but there is a need to explore low-cost, environment-friendly, non-toxic, abundant, and biodegradable electrode materials for supercapacitors. In this regard, biopolymers are observed to be popular for storage applications as they are of high porosity, cost-effective, easily available, low-weight, and environment friendly and have biodegradability properties. The biopolymer-based electrode has a desirable morphology and high surface area and exhibits admirable electrochemical properties. The focus of this report is to highlight (i) the inclusive details of supercapacitors and their types along with strategies to improve their electrochemical performance, (ii) biopolymers and their types used for supercapacitor applications, (iii) various synthesis routes that could be adopted for designing electrode materials based on biopolymers for supercapacitors, and (iv) challenges and future scope of biopolymers as the electrode material in supercapacitor applications. The detailed study here in this report is found to be a topic of interest for the scientific community to fabricate and prepare low-cost, eco-friendly, high electrochemical performance exhibiting electrode materials for supercapacitor applications.

Orange peel-derived activated carbon as an electrode material for supercapacitor application using nickel mesh

Orange peel-derived activated carbon as an electrode material for supercapacitor application using nickel mesh

2D g-C3N4 decorated with 1D Bi2S3 nanocomposite as a high performance electrode material for asymmetric supercapacitors

Energy accumulation and storage is one of the most vital areas and necessities in today's world. The supercapacitor is seen as one of the most promising energy storage devices for upcoming generations. In this work, two dimensional (2D) g-C3N4 nanosheets decorated with one dimensional (1D) Bi2S3 nanorods by using rapid and simple hydrothermal method. The structure, functional groups, morphology and elemental analyses of synthesized materials were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDAX). In electrochemical study, pure Bi2S3 nanorods, g-C3N4 nanosheets, and Bi2S3/g-C3N4 composite electrode material were tested. In compared to pure samples, the Bi2S3/g-C3N4 composite demonstrated high specific capacitance of 631 Fg-1 at a current density of 1 Ag-1, as well as outstanding cyclic stability of 94% retained over 5000 cycles at a maximum current density in aqueous Na2SO4 electrolyte. The Bi2S3/g-C3N4 composite electrode exhibits superior electrochemical performance owing to the synergetic effect of Bi2S3 nanorods and g-C3N4 nanosheets. Also, the Bi2S3/g-C3N4 composite has been suggested as an excellent electrode material for supercapacitor applications. The fabricated Asymmetric supercapacitor device (ASC) has high specific capacitance of 80 F g−1 with 89% capacitance retention after 5000 cycle at current density of 10 A g−1. The ASC device achieved maximum energy density of 44.4 Wh kg−1 at 999 W kg−1 in operating potential range 0–2 V. Also ASC device fabricated for practical application and tested by charging 30 S and attained a self-discharging time of 3 min.

Electrospun 1D cobalt pyrophosphate porous nanofibers: Redox-active electrode material for asymmetric supercapacitor

The ability of a supercapacitor to store energy is closely tied to the amount of surface area available for electroactive reactions. Using 1D nanostructure material not only allows for larger specific surface area compared to that of other nanostructures, but also provides a direct path for the movement of electrons, acting like a “freeway” in the axial direction. Considering the benefits herein, we report the synthesis of Co2P2O7 nanofibers as an electrode material for supercapacitor application using a facile and industrially applicable electrospinning method followed by calcination. The resulting nanofibers have a continuous, uniform, and web-like structure with many small pores, which gives high specific surface area of 234.499 m2 g−1. This high surface area improves the interaction between the Co2P2O7 nanofibers electrode and 3 M KOH electrolyte, thereby enhancing the electrochemical properties of the material. The prepared Co2P2O7 nanofibers electrode has a high specific capacity of 270.7 C g−1 at a high current density 80 A g−1 and good stability of 84.7 % after 3000 continuous cycles. Furthermore, an asymmetric supercapacitor (ASC) device was fabricated using carbon nanofibers (CNF) as another electrode material. The energy density 27.8 Wh kg−1 and power density 1.89 kW kg−1 of ASC at a current density of 2 A g−1 suggests that Co2P2O7 nanofibers could be a viable option as an electrode material for supercapacitors.

Electrochemistry of Titanium Carbide MXenes in Supercapacitor.

Novel electrode materials are always explored to achieve better performance of supercapacitors. Titanium carbide MXenes, Ti3 C2 Tx , are one of the very promising candidates for electrode materials in supercapacitors due to their unique structural and ion storage properties as 2D materials. Their large specific surface area, adjustable functionalized surface terminals, high electrical conductivities, hydrophilicity, and high Faradaic capacitance, also known widely but confusingly as pseudocapacitance, are highly desirable for making high-performance electrodes with increased dis-/charging rates and capacities. Herein, some selective electrochemical considerations of Ti3 C2 Tx MXenes for uses in supercapacitors are critically reviewed and assessed, aiming at a better fundamental understanding of the electrochemical basics and processes in Ti3 C2 Tx MXene-based electrode materials for supercapacitor applications.

Biomimetic [AV-Er2O3-doped δ-Bi2O3]-stacked nanoplates: an efficient electrocatalyst for OER/HER and electrode material for supercapacitor application

Biomimetic [AV-Er2O3-doped δ-Bi2O3]-stacked nanoplates: an efficient electrocatalyst for OER/HER and electrode material for supercapacitor application

SYNTHESIS, CHARACTERIZATION AND ELECTROCHEMICAL PROPERTIES OF rGO/NiCo2S4 NANOCOMPOSITE FOR SUPERCAPACITOR APPLICATION

In this study, rGO/NiCo2S4 composite materials were successfully synthesized by hydrothermal method. The properties of obtained materials were systematically characterized using XRD, SEM, EDX, and Raman techniques. The electrochemical performance of the materials was evaluated through cyclic voltammetry (CV) and Galvanostatic charge-discharge (GCD) measurements. The results show that the supercapacitor fabricated using rGO/NiCo2O4 could store energy using both double-layer and pseudocapacitor mechanisms with outstanding electrochemical properties. The specific capacity was up to over 2000 F/g at scanning speed of 10 mV/s or 1200 F/g at a current density of 1 A/g, which is 200-250% higher than the specific capacity of NiCo2S4 materials. This result demonstrates that rGO/NiCo2S4 material is a potential electrode material for supercapacitor applications.

Fabrication of Phyllanthus emblica leaves derived high-performance activated carbon-based symmetric supercapacitor with excellent cyclic stability

Porous carbon as an electrode material for supercapacitors has received attention due to its large surface area, excellent electrochemical stability, environmental sustainability, and low-cost scalable production. In this work, we have synthesized activated carbon from waste biomass of Phyllanthus emblica leaves (PELAC) and used it as an electrode material for supercapacitor application. PELAC discloses hierarchical porosity with a high surface area of 1244 m2 g−1 and displays the maximum specific capacitance of 336 F g−1 @ 1 A g−1 using 6 M KOH electrolyte as compared to 1 M Na2SO4 (250 F g−1) and 6 M NaOH (290 F g−1). In KOH electrolyte, good cycling retention (during the course of 24,000 GCD cycles) is achieved as; 98.7 % up to initial 8000 cycles @ 10 A g−1, 96 % up to middle 8000 cycles @ 20 A g−1, and 89 % up to final 8000 cycles @ 30 A g−1 for the same PELAC electrode. Further, to evaluate the supercapacitor performance for a practical device, the symmetric supercapacitor (SSC) device was constructed using PELAC as electrodes with PVA/KOH gel as an electrolyte. The device offers a maximum energy density of 29 W h kg−1 and a higher specific power of 6750 W kg−1. Remarkably, the device unveils an outstanding cycling stability of 95 %, which retained up to 25,000 recurring GCD cycles at high current density of 16 A g−1. Moreover, when two SSC devices were connected in series, the assembly enlightened red and yellow LEDs with good brightness. The long-term durability with a practical demonstration of the present device marks PELAC can be a sustainable and cost-effective candidate for electrochemical energy storage applications.

Easy Synthesis of NiO-Mn2O3@Reduced Graphene Oxide Ternary Composite as Electrode Material for Supercapacitor Application

Easy Synthesis of NiO-Mn2O3@Reduced Graphene Oxide Ternary Composite as Electrode Material for Supercapacitor Application

Characterization and electrochemical properties of Carbon/CeO2 composites prepared using a hydrothermal method

The electrochemical performance of carbon was improved by forming composites with CeO2 nanoparticles as an electrode material for supercapacitor applications. The carbon/CeO2 composites were prepared using a hydrothermal treatment with polyvinylpyrrolidone (PVP) referred to as carbon/CeO2-PVP or sodium hydroxide (NaOH) referred to as carbon/CeO2–NaOH. CeO2-PVP and CeO2–NaOH nanoparticles with no carbon composite were also prepared for comparison. All samples were characterized using X-ray diffraction (XRD), Raman spectroscopy (Raman), field emission scanning electron microscope, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), the Brunauer-Emmett-Teller and a potentiostat/galvanostat electrochemical cell system. XRD, Raman and TEM results confirmed the formation of a composite between carbon and CeO2 nanoparticles. XPS measurements of Ce ions in the samples indicated Ce3+ and Ce4+. Specific capacitances at a current density of 0.25 A/g were 64.1, 123.8 and 139.2 F/g for electrodes made from carbon, carbon/CeO2-PVP and carbon/CeO2–NaOH, respectively. Capacitance values of these composites were higher than that of carbon due to the contribution of the redox reaction of Ce3+/Ce4+ within the CeO2 nanoparticles.

Experimental and theoretical insights into colossal supercapacitive performance of graphene quantum dots incorporated Ni3S2/CoS2/MoS2 electrode

Transition metal sulfides (TMS) are promising electrode materials for supercapacitor applications due to their unmatchable advantages. To overcome the deficiency of individual metal sulfides, the combination of one or more pseudocapacitive transition metals with conductive carbon material can be a plausible solution. In this work, a simple and one-step hydrothermal synthesis method is used to fabricate the flower-like Ni3S2/CoS2/MoS2 (NCMS) and Ni3S2/CoS2/MoS2-GQDs (NCMS-G) directly on Ni foam and used it as a binder-free electrode for high-performance supercapacitor applications. The NCMS-G-2.5 electrode possessed colossal specific capacitance (2364 Fg−1 at the current density of 2 Ag−1), excellent rate capability (55 % at the current density of 10 Ag−1), as well as good cycling stability (93 % retention after 10,000 cycles at the current density of 20 Ag−1). Furthermore, assembled NCMS-G-2.5//rGO asymmetric supercapacitor (ASC) device delivered an excellent energy density of 84.8 Wh kg−1 and superior cycling performance (98 % capacitance retention after 10,000 cycles). We have investigated the interactions between Ni3S2/CoS2/MoS2 and carbon based nanostructure GQDs employing state-of-the-art Density Functional Theory (DFT) simulations. The interactions between Ni3S2/CoS2/MoS2 and GQDs is not only long range van der Waals interactions, but also chemical interactions involving charge transfer from metal 3d orbital to C 2p orbital of GQDs are also present. Due to this synergic effect, there is enhancement in electronic states near Fermi level which may improve the conductivity of the hybrid structure. Enhanced quantum capacitance, improved conductivity and increased surface area for the hybrid structure may attribute towards superior charge storage performance for the hybrid structures which support experimental data. It is expected that the fabricated, unique, 3D flower NCMS-G-2.5 has potential prospects for developing advanced and high-performance energy storage devices.

Oxygen and nitrogen-doped carbon particles derived from pyrolysis of Chlorella vulgaris and Spirulina platensis microalgae as an efficient electrode material for supercapacitor application

This study consists of the thermal activation of Chlorella vulgaris and Spirulina platensis microalgae with a potassium hydroxide (KOH) chemical agent in a carbon dioxide (CO2) atmosphere and the formation of nitrogen and oxygen-doped material from the hydrothermal interaction of the obtained activated carbons with nitric acid. The obtained nitrogen and oxygen-doped activated carbons were used in the production of electrochemical super capacitors. The morphological properties of the obtained pores were evaluated by transmission electron microscopy (TEM). Electrochemical properties were evaluated according to the cyclic voltammetry (CV) method in sulphuric acid (H2SO4), potassium chloride (KCl), and sodium hydroxide (NaOH) electrolytes with a scanning rate in the range of 2.5–50 mVs−1. Nitrogen and oxygen doped electrode electrochemical capacitor based on Spirulina platensis microalgae showed the highest specific capacitance of 99.53 Fg−1 at a scanning rate of 2.5 mV s−1 in 1 M H2SO4 electrolyte. In contrast, the supercapacitor based on an activated carbon electrode from Chlorella vulgaris microalgae showed the highest specific capacitance of 156.04 Fg−1 at a scan rate of 2.5 mV s−1 in 1 M KCl electrolyte.

Fabrication of novel M-Type cobalt doped barium hexaferrite nanoplatelets /graphitic carbon nitride composite for efficient supercapacitor applications

Supercapacitors have a wide range of possible uses as energy storage systems. In this study, we examined a new type of composite electrode material for supercapacitor applications made of M-Type cobalt doped barium hexaferrite nanoplatelets (BaCoFe11O19 NPs) and graphitic carbon nitride (g-C3N4) by a two step process. The successful formation of composite material is confirmed by analyses such as XRD, FTIR, TEM, and XPS. The fabricated BaCoFe11O19/g-C3N4 composite electrode has a maximum specific capacitance of 314.6 F g−1 at a current density of 0.5 A g−1. It also retains its cycling stability with 94.3% capacitance retention after 10,000 charging-discharging cycles. As a result, the resultant BaCoFe11O19/g-C3N4 composite electrode has potential for use as an electrode material in high-performance energy storage systems.

Ni-doped CeO2 decorated delaminated layered titanium carbonitride (d-Ti3CN) MXene for potential applications in symmetric supercapacitors

Nickel-doped cerium oxide nanoparticles were decorated on delaminated Titanium carbonitride MXene described as (d-Ti3CN@NiCeO2) through one step in-situ hydrothermal method. The nanocomposites were characterized through several techniques (XRD, XPS, SEM, and STEM). d-Ti3CN MXene as well as d-Ti3CN@NiCeO2 was fabricated and as an electrode material for supercapacitor applications and their performance was evaluated using cyclic volatmmetery, galvanostatic charge-discharge, and electrochemical impedance spectroscopy. Results showed that the synergistic effect of d-Ti3CN MXene and NiCeO2 nanoparticles in d-Ti3CN@NiCeO2 electrode material were responsible for better capacitance and stability. This novel material exhibited outstanding specific capacitance (444 F g−1 at a current density of 1 A g−1), low internal resistance, and outstanding cyclic stability (79% after 8000 cycles). d-Ti3CN@NiCeO2 displayed exceptional specific capacitance (41 F g−1 at 10 A g−1) as compared to that of d-Ti3CN MXene (28 F g−1), as well as high energy density (5.7 Wh kg−1). The results demonstrate that d-Ti3CN@NiCeO2 is an efficient electrode material with superior electrochemical performance and can be potentially applied for fabrication of symmetric supercapacitors.

Intrinsic Properties of GO/RGO Bilayer Electrodes Dictate Their Inter-/Intralayer Intractability to Modulate Their Capacitance Performance.

The demand for high-capacity energy storage along with high power output and faster charging has made supercapacitors a key area of energy research. The charge storage capacity of capacitors is largely dependent on the electrode materials utilized. To that end, graphene oxide (GO) and reduced GO (RGO) have been extensively employed for preparing supercapacitors. However, to date, no study has reported utilizing a GO/RGO bilayer electrode material for supercapacitor application. Herein, we report the synthesis of GO/RGO bilayer electrodes on fluorine-doped tin oxide (FTO) conducting substrates with four different combinations, namely, RGO-RGO, RGO-GO, GO-RGO, and GO-GO. Electrochemical capacitance analysis based on a symmetrical electrode configuration revealed that FTO-GO-RGO electrodes had the best areal capacitance performance. However, the highest specific areal capacitance (27.85 mF/cm2) for both symmetric/asymmetric configurations was achieved with FTO-GO-RGO as the anode and FTO-GO-GO as the cathode. The heterogeneous capacitance performance of the GO/RGO bilayer systems was analyzed based on structural characterization and computational simulation methods. Based on our analysis, we identified that inter-/intralayer molecular interaction of the GO/RGO bilayer sheets through the confinement pressure effect might have prompted their unique physicochemical properties. This work highlights the importance of probing multilayer GO/RGO electrode fabrication methods for preparation of high-capacity supercapacitors through fine-tuning their structural and molecular properties.

The exploration and synthesis of perovskites La0.2Sr0.8MnO3 electrode material for supercapacitor application.

The exploration and synthesis of perovskites La0.2Sr0.8MnO3 electrode material for supercapacitor application.

Coalescing of lanthanum oxide and PPy @graphitic carbon nitride to achieve ultrahigh energy density electrode material for supercapacitors applications

Faster charging and discharging rate and long cycle life make supercapacitors compatible for energy storage devices. However, supercapacitors' poor energy density prevents them from replacing batteries. This study reports a facile method of synthesizing PPy/g-C3N4/La2O3 (LGP) nanocomposite electrodes via in-situ polymerization by varying the lanthanum oxide concentration. The electrochemical application of synthesized nanocomposites was performed in 1 M H2SO4 by cyclic voltammetry (CV), Galvanostatic Charge Discharge (GCD) and electrochemical impedance spectroscopy (EIS). It was observed that the addition of lanthanum oxide has a synergistic effect on already reported PPy/g-C3N4 composite resulting in a specific capacitance of 1763.56 F g−1 at 10 mV s−1 with ultrahigh energy density of 198.18 W h kg−1 and power density of 450.01 W kg−1 at a current density of 1 A g−1 for 0.4 LGP. From EIS studies, the solution resistance was 1.53 ohm and the charge transfer resistance was 0.50 ohm for PPy, while for 0.4 LGP it was 1.00 ohm and 0.23 ohm respectively. Additionally, the capacitance of 0.4 LGP composite increased to 131% after 10,000 cycles showing the enhanced cyclic stability of electrode material in 1 M H2SO4 electrolyte demonstrating its capability as an electrode material for future supercapacitors.

Hydrothermal synthesis of GO/ZnO composites and their micromorphology and electrochemical performance

In this study, a graphene oxide/zinc oxide (GO/ZnO) composite was synthesized by the one-pot hydrothermal technique using various GO/ZnO ratio compositions. These were characterised by scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) and Raman spectroscopy. The findings reveal that the GO/ZnO composite has three different micromorphologies: ZnO-nanorods (ZnO-NRs) were embedded and agglomerated over the GO surface; ZnO-microrods (ZnO-uRs) adhered to and separated on the GO surface; and GO was coated by ZnO at 1:1, 1:2 and 1:8 ratios. In addition, the electrochemical performance of the synthesized GO/ZnO composites was investigated using cyclic voltammetry (CV). The results show that the embedded and agglomerate of ZnO-NRs over the GO surface have the best performance, indicated by a larger CV curve area and higher specific capacitance than the GO and other GO/ZnO composites. The results indicate that the incorporation and insertion of GO and ZnO NRs have an effective reversible nature and are promising electrode materials for supercapacitor applications.

Microwave‐Induced Rapid Synthesis of MoS2@Cellulose Composites as an Efficient Electrode Material for Quasi‐Solid‐State Supercapacitor Application

Transition‐metal dichalcogenides (TMDs) are highly desired for energy‐storage devices due to their intrinsic layered structure, huge surface area, and the large number of active sites. However, the TMDs fail to reach their potential due to restacking of 2D layered structures that remains a major technological hurdle. Herein, MoS2 nanosheets and cellulose fiber binary composite (MoS2@Cellulose) prepared by the microwave‐assisted technique are demonstrated as an electrode material for supercapacitor application. The prepared material are tested in symmetric and asymmetric all solid‐state device assemblies. It is found that the quasi‐solid‐state symmetric and quasi‐solid‐state asymmetric supercapacitors exhibited remarkably higher specific capacitance of ≈294 and ≈177 F g−1 at a current density of 1 A g−1, respectively, than their counterpart. Furthermore, the symmetric and asymmetric devices deliver excellent energy densities of ≈40.84 and ≈42.67 Wh kg−1 while maintaining the power density of 400 and 791.81 W kg−1, respectively, and outstanding cyclic stability. The cellulose entanglement causes a reduction in the aggregation and restacking of MoS2, which may improve the electrochemical performance of the supercapacitor. Herein this research, a pathway is provided to create an efficient energy‐storage system using 2D materials with sustainable cellulose.