Electrode Material For Supercapacitor Applications Research Articles

Fabrication of novel chitosan decorated reduced graphene oxide/cobalt oxide hybrid nanocomposite electrode material for supercapacitor applications

Supercapacitors are considered efficient electrochemical energy storage devices due to their high-power density, long cycling stability, and quick charge–discharge rates. Despite exhibiting high power density and cycling stability, the electrode materials are toxic and non-degradable, continuously affecting the environment. Biopolymers are a suitable alternative to conventional electrode materials since they possess interesting properties such as unique structure, biodegradability, abundant availability, and efficient interaction with other materials. This study aims to synthesize chitosan (CS) based nanocomposites, namely CS-rGO, CS-Co3O4, and CS-rGO-Co3O4 hybrid nanocomposites by an effective simple strategy method. XRD results show well-intensified peaks confirming the formation of nanocomposites. SEM and HR-TEM analysis indicates the cobalt oxide nanoparticles diffused in the sheet-like structure of CS-rGO which is evident for the porous nature of the CS-rGO-Co3O4 hybrid nanocomposite. A novel CS-rGO-Co3O4 hybrid nanocomposite showed surpassing electrochemical performance compared to other synthesized binary composites. The hybrid composite exhibited a high specific capacitance of 361.31 Fg−1 with an electroactive surface area of 136.880 m2g−1. In GCD, the hybrid composite demonstrates a 70 % capacitance retention and 99 % Coulombic efficiency after 10,000 cycles. An asymmetric hybrid supercapacitor is assembled using CS-rGO-Co3O4 nanocomposite as an anode and activated carbon as a cathode. The assembled AHS device delivers a high specific capacitance of 75.7 Fg−1 at 0.5 Ag−1. The energy density of the CS-rGO-Co3O4 hybrid nanocomposite is 23.6 WhKg−1 and the power density is 734.15 WKg−1. Hence, our research provides valuable insights for developing high-performance supercapacitor electrodes.

Hydrothermally synthesized nitrogen-doped hydrochar from sawdust biomass for supercapacitor electrodes

Porous carbon generated from biomass is among the most promising electrode materials for supercapacitor applications. In this research work, sawdust was used as a carbon source to synthesize N-doped hydrochars via the hydrothermal method in the presence of nitrogen-containing compounds including ammonium chloride, urea agar, ammonium molybdate tetrahydrate, and mammalian urine, followed by chemical activation by potassium hydroxide. Using the hydrothermal technique, it was possible to dope 7.06 wt% of nitrogen into the hydrochar. The as synthesized materials were characterized by TGA/DTA, FTIR, BET, XRD, SEM/EDS, XPS, and proximate analysis. Furthermore, EIS, CV, and GCD were used to assess electrochemical performance. All the N-doped hydrochars synthesized samples possess crystalline and mesoporous structures with hydroxyl and amide functional groups. The KOH activation improved the specific surface area and pore volume by 8.5 % and 21 %, respectively. The maximum specific surface area and pore volume were found to be 560.72 m2/g and 0.2246 cc/g, respectively. The CV findings demonstrate the battery-like characteristics of the electrocatalysts made with molybdenum (VI) oxide (MoO3) embedded in these N-doped hydrochars, yielding 35.16 F/g specific capacitance at 10 mV/s. In contrast, the GCD's specific capacitance displays 80 F/g at 0.5 Ag−1.

Optimisation of a ternary composite of CuFe2O4/CuO@rGO and its electrochemical evaluation as an electrode material for supercapacitor applications

Optimisation of a ternary composite of CuFe2O4/CuO@rGO and its electrochemical evaluation as an electrode material for supercapacitor applications

Temperature-dependent electrochemical performance of CuS as electrode material for supercapacitor application

In this work, we synthesize copper sulfide as electrode materials using hydrothermal technique at different temperatures. The electrochemical performance of copper sulfide electrode in 3-electrode systems using 2 M KOH electrolyte is thoroughly studied using electrochemical techniques such as CV, GCD and EIS. The sample synthesized at 160 °C demonstrates that it has a specific capacitance of 232.5F/g at a charge–discharge current density of 1 A/g, maintains cyclic stability of 72.57 % during 500 GCD cycles at 5 A/g, highlighting its potential for supercapacitors applications. The results demonstrate that temperature significantly alters the electrochemical properties of the CuS.

Facile Synthesis of Colocasia esculenta Peels‐Derived Activated Carbon for High‐Performance Supercapacitor

ABSTRACTBiomass and biowaste resources can be used to create self‐doped carbon with a distinctive microstructure. Using an economical and environmentally friendly method to create heteroatom‐doped carbon electrode materials with excellent electrochemical performance has attracted much attention in the energy storage industry. A novel facile two‐step, low‐cost, and eco‐friendly synthesis method for Colocasia esculenta peels has been developed to manufacture activated carbon (CEPAC) and used as an electrode material for supercapacitor application. The CEPAC 1:1 displayed a high specific surface area of 910 m2/g with oxygen‐heteroatom polar sites in the carbon network. A specific capacitance of 525.3 F/g was recorded in the three‐electrode system using a 3 M KOH solution. The assembled symmetric cell delivered an impressive specific capacitance of 98.7 F/g at 1 A/g while maintaining 98.4% of the initially recorded capacitance after 10 000 charge–discharge cycles. These results present a promising low‐cost and simple processing route for synthesizing electrode materials with superior surface properties for high‐performance supercapacitors.

Electrochemical performance of composite phase copper vanadate for promising electrode material for supercapacitor applications

Electrochemical performance of composite phase copper vanadate for promising electrode material for supercapacitor applications

Supercapacitor devices based on multiphase MgTiO3 perovskites doped with Mn2+ ions

Recently, perovskites have become a hotspot for researchers attempting to exploit metal and oxygen vacancies in structures of the form MTiO3, facilitating the convenient electron/hole migration, thus displaying interesting properties. Magnesium Titanate (MgTiO3) is a prominent part of the perovskite class, exhibiting remarkable electrical, thermal, and chemical properties. Undoped and Mn-doped MgTiO3 samples were obtained using a solid-state reaction starting from previously synthesized MgO and TiO2 powders, which were separately doped with different Mn ion concentrations. The resulting multiphase materials with a major MgTiO3 phase were thoroughly morpho-structurally analyzed employing XRD, STEM, Raman, PL, XPS, and EPR spectroscopy. The electrochemical results indicate that they show superior performance when used as electrode materials for supercapacitor application due to the high defect concentration as shown in EPR and PL spectroscopy and the ferroelectric behavior observed in XPS and XRD. When used in symmetric and asymmetric supercapacitor devices, they show promising results, with specific capacity values reaching up to 109 F/g for the symmetric and 609 F/g for the asymmetric devices, while energy and power density values reached 84.7 Wh/kg and 90.8 kW/kg respectively, proving a great potential in the energy storage field.

Synthesis of boron-doped reduced graphene oxide as electrode material for supercapacitor applications

Synthesis of boron-doped reduced graphene oxide as electrode material for supercapacitor applications

Compositing LaSrMnO3 perovskite and graphene oxide nanoribbons for highly stable asymmetric electrochemical supercapacitors

The anticipated large contribution of renewable energy resources to the sector of energy production strongly motivated the development of energy storage technologies, of which supercapacitors have drawn a lot of attention. In this work, Lanthanum-Strontium-Manganese-oxide (LSMO) perovskite nanoparticles, graphene oxide nanoribbons (GONRs), and LSMO-GONRs composite were synthesized and tested as electrode materials for supercapacitor applications. The LSMO was synthesized using the co-precipitation/calcination method, while the GONRs were synthesized using the oxidative unzipping of multi-walled carbon nanotubes. The physical/chemical structures were studied using XRD, FT-IR, SEM, TEM, SAED, and XPS. In 1 M KOH, the LSMO-GONRs electrode exhibited a specific capacitance of 490F/g compared to 342F/g and 294F/g for GONRs and LSMO electrodes, respectively, at 1 A/g, showcasing a performance that is not just superior but truly impressive, to the different types of perovskite/carbon-based material composites. The fabricated asymmetric SC device of LSMO-GONRs//GONRs exhibited a potential window of 1.7 V, a specific capacitance of 92.3F/g, an energy density of 38 Wh/kg, and a power density of 860 W/kg at 1 A/g. Moreover, the LSMO-GONRs//GONRs device showed excellent capacity retention and Coulombic efficiency after 10,000 cycles at 10 A/g, revealing the promising employment of LSMO-GONRs composite as a highly stable material for supercapacitor applications.

Green synthesis of NiO and NiO@graphene oxide nanomaterials using Elettaria cardamomum leaves: Structural and electrochemical studies

An eco-friendly synthetic route was developed for the formation of nickel oxide (NiOaq and NiOet) nanoparticles (NPs) by treating Ni(NO3)2.6H2O with aqueous/ethanolic extracts of Elettaria cardamomum leaves; the same reaction was performed in the presence of graphene oxide (GO) to produce NiOaq@GO and NiOet@GO nanocomposites (NCs), respectively. The NMs were characterized by XRD, FT-IR, SEM, EDX, UV–visible spectroscopy, and TGA-DSC analysis. They were also subjected to electrochemical investigations and photocatalytic degradation of crystal violet (CV) dye. XRD analysis revealed the average crystallite sizes of 8.84–14.07 nm with a face-centered cubic form of NiO NPs and a hexagonal structure of their nanocomposites with GO. FT-IR spectroscopy confirmed the presence of Ni-O vibrations at 443-436 cm−1. SEM images confirmed the spherical morphology of NiO NPs while NiOaq@GO NCs contained randomly aggregated, thin, and wrinkled graphene sheets. NiOaq and NiOet have shown particle sizes of 27.7–30.63 nm which were decreased to 19.33–26.39 nm in their respective NiOaq@GO and NiOet@GO NCs. EDX spectra verified the homogeneous distribution of elements (Ni, O, C) on the surface of the particles. The synthesized NCs have shown smaller band gaps (NiOaq@GO = 3.74 eV; NiOet@GO = 3.34 eV) as compared to their respective NPs (NiOaq = 5.0 eV; NiOet = 3.89 eV). TGA/DSC data was used to find the thermal stabilities, glass transition temperatures, and enthalpies. Cyclic voltammetry measurements exhibited distinct oxidation and reduction peaks. NCs exhibited better potential as electrode materials for supercapacitor applications as compared to their respective NPs. NiOet@GO exhibited the best electrochemical performance and photocatalytic degradation efficiency of CV dye. After 120 min exposure to sunlight, the degradation coefficient of CV was observed to be 82.93, 86.34, 89.99, 90.27 and 81.65 % in the presence of NiOaq, NiOet, NiOaq@GO, NiOet@GO and GO, respectively.

Facile combustion synthesis of Granular-like La1-xSrxMnO3 Perovskites as electrode material for supercapacitor application

This study focuses on synthesizing a series of perovskite-type La1-xSrxMnO3 materials using a solution combustion method to investigate the impact of varying concentrations of La and Sr. The samples were prepared with different La and Sr concentrations (La1-xSrxMnO3, X = 0, 0.2, 0.4, 0.6, and 0.8) and labeled as LSMO-2 (La0.8Sr0.2MnO3), LSMO-3 (La0.6Sr0.4MnO3), LSMO-4 (La0.4Sr0.6MnO3), LSMO-5 (La0.2Sr0.8MnO3. The structural, morphological, and compositional characteristics of the synthesized electrodes were thoroughly analyzed. X-ray diffraction (XRD) confirmed the formation of a rhombohedral structure with an R-3c space group, while Fourier-transform infrared spectroscopy (FT-IR) verified the presence of all functional groups in the samples. Field emission scanning electron microscopy (FE-SEM) revealed a cluster of nanopowder morphology, and compositional analysis further validated the formation of the prepared samples. The electrodes were then screen-printed onto Ni-foam and evaluated for their electrochemical performance. Notably, the La1-xSrxMnO3 electrode demonstrated a high specific capacitance of 1271.5 F/g at a current density of 10 mA/cm2 and maintained 83.45 % cyclic stability after 10,000 cycles. Moreover, the power law was employed to investigate the charge storage mechanism of the LMSO-4 electrode. To assess the practical application potential of the La1-xSrxMnO3 electrode, a solid-state supercapacitor device was fabricated, and its performance was investigated. The device achieved a maximum specific capacitance of 206 F/g at 5 mA, with an energy density of 16 Wh/kg and a power density of 2400 W/kg, retaining 94 % of its performance after 5000 cycles. Overall, La1-xSrxMnO3 electrodes show great promise as materials for supercapacitor applications due to their impressive electrochemical properties.

Cu-Zn layered double hydroxides as high-performance electrode for supercapacitor applications

Supercapacitors have evoked considerable attention nowadays under the realm of energy storage devices due to some of their intriguing properties such as long cycling stability, high power density, and low cost. Layered double hydroxides, known for their unusual structural and electrochemical properties, have gained prominence among electrode materials due to their high specific capacitance and exceptional cycle stability. This study investigates the viability of Cu-Zn layered double hydroxides (LDH) as electrode material for supercapacitor applications. Copper (Cu) and Zinc (Zn) present in the LDH framework create synergistic effects that increase the material's electrochemical properties. The current study investigates the morphology and electrochemical behaviour of Cu-Zn LDH, emphasizing their suitability as supercapacitor electrodes. Furthermore, various characterization techniques such as XRD, FTIR, SEM, TEM, and XPS were employed to uncover the material's inherent properties. A specific capacitance of 265 F/g was obtained at a current density of 1 mA/cm2 in the three-electrode configuration. Further, an asymmetric device furnished a specific capacitance of 51 F/g with an energy density of 7.14 Wh/kg and a power density of 121.94 W/kg. Additionally, the material maintains 75 % of its original capacitance after 1000 cycles, demonstrating its exceptional stability. The obtained electrochemical parameters for the as-synthesized material demonstrate its feasibility as an energy storage device.

Shape tailored nano-ceria as high performance supercapacitor electrode material

Electrochemical energy storage devices herald a brighter future, offering efficient and sustainable solutions to meet the escalating global energy demands. The current work investigates the development and characterization of different ceria nanostructures (nanorod, nanocube, and nanopolyhedra) as effective electrode materials for supercapacitor applications. The electrode materials are systematically characterized using various spectroscopic and non-spectroscopic techniques. Galvanostatic charge-discharge, electrochemical impedance spectroscopy, and cyclic voltammetry techniques are used to evaluate the electrochemical performance of the electrode materials. The optimum material for the said application is cerium nanorod which has the maximum specific capacitance of 437.27 F/g in acid electrolytes. The current-voltage (I-V) characteristics of the ceria nanostructures exhibit hysteresis behavior; ceria nanorod showing coexistence of memristive and memcapacitive nature. The loop area of the hysteresis curve, derived from the ratio of OFF resistance to ON resistance (ROFF/RON) at 4 V, yields approximate values of 1.08, 1.33, and 1.57 for ceria nanocubes, ceria nanopolyhedra, and ceria nanorods, respectively. Impedance vs. frequency analysis of the samples was also carried out to study their electrical and transport properties. The results obtained from electrochemical analyses are complimented by electrical studies.

Facile synthesis of MOF-derived carbon-supported LaZn@C nanocomposite as an efficient electrode material for supercapacitor

MOF-derived transition metal alloys have attracted researcher's interest in energy storage devices due to their vast surface area, high porosity, adjustable pore sizes, ease of modification, abundant active sites, and 3D tunable structure. Metal alloys covered with carbon can stabilize conductivity and ease charge accumulation, and they are suitable candidates for electrode materials for supercapacitor application. In this research article, core-shell LaZn@C nanocomposites were fabricated at different pyrolysis times via a hydrothermal approach. The materials that pyrolysis for two hours have a remarkable specific capacitance of 1024 F g−1 at 1 A g−1 and an impressive energy density of 36.9 Whkg−1. In addition, it has lower Rp∼0.8 Ω and Rs∼0.2 Ω resistance due to the large surface area's high carbon content with cylindrical particles. Moreover, it shows an outstanding retention rate of (94.5 % over 4500 cycles at 1 A g−1). Finally, this research showed the novelty of advanced MOF-derived materials that suggest an efficient electrode material for the electrochemical performance of energy storage devices and supercapacitor applications.

α-Bi2O3 tubular rods coated on Bi2O2CO3 nanosheets for high-performance asymmetric supercapacitor applications

Mixed phases of bismuth oxide nanostructures as an active electrode material in supercapacitor applications have recently gained huge research interest. In this study, the layered Bi2O2CO3 nanosheets and the secondary phase of α-Bi2O3 tubular rods named Bi2O2CO3/α-Bi2O3 heterostructure have been synthesized and utilized for supercapacitor applications. The crystal nature and microstructure of the Bi2O2CO3/α-Bi2O3 heterostructure were initially confirmed by powder X-ray diffraction (p-XRD), Raman, UV-Vis diffuse reflectance spectroscopy (UV-DRS, absorbance), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) studies. X-ray photoelectron spectroscopy (XPS) measurements have investigated the oxidation states and chemical binding energies. Regarding the electrochemical performances, the Bi2O2CO3/α-Bi2O3 heterostructure as electro-active material delivered a maximum specific capacitance (Cs) value of 635 F g−1 at the given current density value of 1 A g−1 in a conventional three-electrode mode. A coin cell type electrode has been fabricated using Bi2O2CO3/α-Bi2O3 heterostructure, resulting in an asymmetric supercapacitor device cell (ASC), which has a Cs of 112 F g− 1 (at 1 A g− 1) and a power density and energy density values of 515 W kg−1 and 22.5 Wh kg−1 respectively. The two supercapacitor electrodes in sequence effectively ignite the red-light-emitting diode (LED). Moreover, in the ASC type Bi2O2CO3 /α-Bi2O3 heterostructure, the specific capacitance value was slightly reduced to 12.3 % by 2000 cycles, showing favourable cyclic performance and stability during the electrochemical process. Based on the above-mentioned characterization, the appropriate electrochemical performances of Bi2O2CO3/α-Bi2O3 tubular rod heterostructures make them a promising candidate for future energy storage devices.

Conducting Polymer-Based Gel Materials: Synthesis, Morphology, Thermal Properties, and Applications in Supercapacitors.

Despite the numerous ongoing research studies in the area of conducting polymer-based electrode materials for supercapacitors, the implementation has been inadequate for commercialization. Further understanding is required for the design and synthesis of suitable materials like conducting polymer-based gels as electrode materials for supercapacitor applications. Among the polymers, conductive polymer gels (CPGs) have generated great curiosity for their use as supercapacitors, owing to their attractive qualities like integrated 3D porous nanostructures, softness features, very good conductivity, greater pseudo capacitance, and environmental friendliness. In this review, we describe the current progress on the synthesis of CPGs for supercapacitor applications along with their morphological behaviors and thermal properties. We clearly explain the synthesis approaches and related phenomena, including electrochemical approaches for supercapacitors, especially their potential applications as supercapacitors based on these materials. Focus is also given to the recent advances of CPG-based electrodes for supercapacitors, and the electrochemical performances of CP-based promising composites with CNT, graphene oxides, and metal oxides is discussed. This review may provide an extensive reference for forthcoming insights into CPG-based supercapacitors for large-scale applications.

The phosphorous-doped 2D nanosheet assembled 3D Mn2V2O7 microflowers on Ni foam as a binder-free electrode for high energy density asymmetric supercapacitor application

In recent times, transition-metal oxides have been recognized as highly promising candidates for supercapacitor applications. Nevertheless, their progress in diverse fields has been hindered by challenges such as poor electrical conductivity and a shortage of active reaction centers. Doping heteroatoms would overcome these drawbacks and enhance the supercapacitor properties in transition metal oxides. Herein, the phosphorous-doped 2D nanosheet assembled 3D Mn2V2O7 micro flowers were grown on the Nickel foam using the hydrothermal method and successively phosphatized in a tube furnace, which was utilized as a binder-free supercapacitor electrode. The synthesis process involved varying the concentration of phosphorus (P), resulting in the successful formation of uniform P-decorated Mn2V2O7 microflowers. The unique microflower structure and doping P into the Mn2V2O7 material enhance the electrochemical properties with a specific capacity of 850C g−1 (1545 F g−1) at 1 A g−1 in a three-electrode cell. Moreover, the assembled Mn2V2O7–600/NF//AC device delivers a specific capacity of 258C g−1 (211 F g−1) at 1 A g−1 with a remarkable rate of 47 % at a high current density of 20 Ag −1. The device achieved a maximum energy density of 43.2 Wh kg−1 at a power density of 604.7 W kg−1, and it maintained 91 % of initial capacity after 10,000 charge/discharge cycles at 20 A g−1. These results suggest that the P-doping 2D nanosheet assembled 3D Mn2V2O7 could be promising electrode materials for supercapacitor applications.

Mg‐ZnO/CNT Nanocomposite as Electrode Materials with Enhanced Electrochemical Performance for Supercapacitor Applications

AbstractThe present research work reported the study of nanocomposites of undoped and Mg‐doped ZnO with CNT as electrode materials for supercapacitor application. The undoped ZnO/CNT and Mg‐doped ZnO/CNT nanocomposites (i.e., 10 % Mg‐doped and 20 % Mg‐doped) were synthesized using a cost‐effective blending‐assisted hydrothermal method. The morphological (FESEM & TEM) studies revealed that the diameter of CNT was ~7 nm and the ZnO nanoparticles were spherical in shape with an average particle size of ~5 nm. In addition, it was also found that 10 % Mg‐ZnO and 20 % Mg‐ZnO had a sheet‐like structure. XRD and FTIR studies further confirmed the successful doping of Mg in ZnO and CNT nanocomposites. BET analysis showed that the value of specific capacitance increased with the increase in surface area. Further, the electrochemical performance of these nanocomposites revealed that the higher doping percentage, 20 % Mg‐ZnO/CNT nanocomposite achieved the highest specific capacitance value i.e., 458.5 F/g at 0.1 A/g current density in 3M H2SO4 electrolytic solution, having a retention of 99.8 % after 12,00 long cycles. In addition, the charge storage mechanism revealed that the as‐synthesized nanocomposites showed both the diffusion‐controlled and capacitive‐controlled behaviors. Thus, a higher value of specific capacitance with excellent cyclic stability indicated the higher efficiency of Mg‐doped ZnO/CNT nanocomposite for future supercapacitor applications.

Simple pyrolysis synthesis of multi-walled carbon nanotubes as a highly stable electrode material for supercapacitor applications

We report the preparation of multi-walled carbon nanotubes (MWCNTs) by using a simple and cost-effective method for supercapacitor applications. The fabricated MWCNTs electrode shows a maximum specific capacitance of 278 F g−1 at 1 A g−1 and 257 F g−1 at 5 mV/s. Also, excellent retention has been achieved in the fabricated MWCNT electrode and 97 % capacitance is retained even after 10,000 cycles. The findings highlight the potential of pyrolysis-synthesized MWCNTs as a viable electrode material for supercapacitors, offering a pathway towards the development of efficient and durable energy storage devices for various applications.

Facile fabrication of Mn doped WSe2 as an electrode material for supercapacitor application

The world is currently confronted with major challenges of energy scarcity and environmental deterioration. Prioritising the development and storage of eco-friendly energy sources is imperative given the finite availability of non-renewable resources. Under these circumstances, the production and utilization of environmentally friendly energy have become widely recognized as of utmost significance. Lately, researchers have shown a strong fascination with supercapacitors owing to exceptional energy/power density and prolonged cycle life. In this work, we have fabricated Mn doped WSe2 through the hydrothermal route for supercapacitor applications. Utilization of Mn2+ as a dopant increases the conductivity of the WSe2 lattice by adding charge carriers, hence enhancing electron mobility. The incorporation of Mn2+ enhanced the electrochemical characteristics of Mn-doped WSe2, resulting in an overall improvement in electrochemical efficacy. The Mn doped WSe2 exhibited Cs of 1908 F/g at 1 A g-1, surpassing the Cs of pure WSe2 (593 F/g). This enhancement was attributed to the rise in the quantity of active sites, lower resistance and improved morphology resulting from to successful doping of Mn2+. It enhances the material's conductivity and charge storage capacity, compelling to increase in capacitance. After 5000th cycle at 10 mV/s, the material showed great cyclic stability due to doping. The superior performance of Mn doped WSe2 electrode suggests its potential for supercapacitor electrodes. The widespread implementation of Mn doped WSe2 can considerably enhance the performance, durability, and cost-effectiveness for it to be utilized further in next-generation energy storage processes.