Fabrication Of Supercapacitor Electrodes Research Articles

Synthesis, fabrication, and performance evaluation of lanthanum doped nickel cobalt ferrite electrode for supercapacitors in energy storage applications

The escalating demand for high-quality energy storage devices has become a paramount concern in the contemporary scenario. Despite the potential of supercapacitors for high-quality energy storage, developing sustainable and improved electrode materials remains a challenge. This work investigates the synthesis and characterization of a novel optimally lanthanum-doped nickel cobalt ferrite, for its potential application in supercapacitors. The synthesized nano ferrite is utilized in a two-electrode system as a symmetrical supercapacitor device. The obtained morphological and electrochemical results of both two and three-electrode systems confirm their suitability for effective deployment in supercapacitor electrodes. A high specific capacitance of 706 F/g and energy density of 152.9 Wh/g is obtained for the fabricated device with a retention capacity of 86 % even after 10,000 cycles. The electrochemical results are also validated using an electrical method. The exploration of this lanthanum-doped nano ferrite is expected to be a suitable candidate for the fabrication of supercapacitor electrodes for augmented energy storage performance.

Utilizing rubber plant leaf petioles derived activated carbon for high-performance supercapacitor electrodes

This research introduces a novel and sustainable method that exploits the untapped potential of waste biomass, specifically converting dead leaf petioles from Ficus elastica, an industrial crop commonly known as rubber plants, into high-performance activated carbon (AC) for supercapacitor electrodes through a straightforward pyrolysis process. The prepared AC is used as an electrode substance to construct symmetrical supercapacitors. It underwent detailed morphological and structural analyses through various analytical instruments to assess the AC's performance and quality. Electrochemical assessments using a two-electrode configuration with 1 M KOH as the electrolyte revealed that the AC electrodes display exemplary characteristics of electric double-layer capacitance. This conclusion was drawn from observing cyclic voltammetry curves that were rectangular and symmetrical across scan rates ranging from 10 to 100 mV/s. Remarkably, at a scan rate of 10 mV/s, these AC electrodes achieved a specific capacitance of 128 F/g. The superior performance of the AC, when compared to other biomass-derived electrode materials, can be attributed to its extensive surface area and significant porosity. Moreover, electrodes crafted from AC derived from rubber plants showed remarkable durability over 10000 charge-discharge cycles, maintaining 89 % of their original capacitance and achieving a Coulombic efficiency of up to 87 %. During prolonged discharge periods, these electrodes exhibited a high specific capacitance, which contributed to achieving a power density of 200 W/kg and an energy density of 11.4 Wh/kg. This study highlights the viability of rubber plant waste in advanced energy storage systems and significantly contributes to sustainable material science. By offering an eco-friendly approach for supercapacitor electrode fabrication, this research aligns with global efforts towards sustainable energy storage technologies, demonstrating the practicality of environmentally benign materials in high-performance applications.

Study and characterization of BaFe12O19/PVDF composites as electrode materials for supercapacitors

Supercapacitors are an interesting energy storage technology to be studied. This research uses mesoporous BaFe12O19 particles and synthesized Polyvinylidene fluoride (PVDF) polymers as materials to obtain high performance supercapacitors. Composites were synthesized by facile one-step method using BaFe12O19 which was prepared through co-precipitation chemical method with a calcination process at 200 °C along with PVDF with variations in sample composition of BaFe12O19, BaFe12O19 20%, BaFe12O19 30%, BaFe12O19 40%, and BaFe12O19 60%. And finally the fabrication of supercapacitor electrodes is carried out. The result of the synthesized material is distributed grains with the average particle size of each sample ranging from 180 to 185 nm. Then it has the highest peak in crystals with a miller index (114). Furthermore, it has the main functional group, Ba–O with a wave number of 1632 cm−1. Furthermore, the best supercapacitor electrode is BaFe12O19/PVDF 60% which produces an area of 0.51 mVA where the greater the surface area, the higher the capacitance obtained. Then at BaFe12O19/PVDF 60% has the highest power density value at 12.36 Wh/kg and the highest power density value at 299.14 Wh/kg. It is expected that the results obtained can be a reference for further electrode material research.

Synthesis of S-doped porous carbon/MnO2 composite from discarded medical masks for hybrid supercapacitor electrodes

Abstract The fabrication of supercapacitor electrodes can be obtained from materials with abundant carbon availability such as discarded polypropylene medical masks, studied by XRD, SEM, and FTIR. In this work, discarded surgical masks and then carbon was obtained via a solvothermal method. The fabrication of high performance supercapacitor to enhance the electrochemical performance of carbon-based electrode is by combining carbon material with MnO2 to form hybrid supercapacitor electrodes. The electrochemical performance can be greatly improved because of the high electrical conductivity of carbon and excellent redox reaction from MnO2. Fibrous structure of S-doped porous carbon morphology via SEM with nanowire MnO2 covered a rod carbon structure. Furthermore, XRD analysis and FTIR show the amorphous structure with high peak at 2θ 25.5⁰ and 42.2° with the absorption peak at 509.05 cm−1, 510.68 cm−1 and 578. 87 cm−1 shows the Mn-O stretching. The as-prepared 0.3-SDPC/MnO2 exhibited the highest specific capacitance of 84.71 F g−1. Moreover, as-prepared 0.3-SDPC/MnO2 showed high energy and power density (7.53 Wh kg−1, 169.96 W kg−1) and the lowest resistance of 0.72 Ω. These results indicate that 0.3-SDPC/MnO2 composite electrode will have potential application in hybrid supercapacitors.

A novel 2D bismuthene-molybdenum disulfide nanocomposite for high energy density supercapacitors and fabrication scaled to pouch cell

Emerging novel 2D materials with unique electrochemical properties generate massive interest among researchers to fabricate the supercapacitors with high energy density without fading actual power density. In present work, a novel 2D Bismuthene-Molybdenum disulfide composite (Biene-MoS2 NC) was synthesized which serves as an effective active material for the fabrication of electrodes for supercapacitors with superior electrochemical characteristics. The synthesized Biene-MoS2 NC electrode provides the improved specific capacity of 195.9 mAh/g at the sweep rate of 10 mV/s together with the total stored capacity, outer surface adsorption capacity, and intercalation capacity of 285, 10.8, and 274.2 mAh/g respectively and their percentage of capacitance and diffusion of 36.3 % and 63.7 % respectively. The pouch type supercapacitor cell was fabricated using Biene-MoS2 NC as positive electrode (cathode) and activated carbon (AC) as negative electrode (anode) which demonstrated high areal capacitance of 38.2 mF/cm2 at the current density of 0.5 mA/cm2 and also it delivered the enhanced areal energy and power densities of 11.94 μWh/cm2 and 1 mW/cm2 respectively.

Multifunctional electrodes based on brochantite/malachite/polyaniline on Ni foam for the fabrication of binder-free supercapacitors and pyrimethanil/carbendazim fungicide electrochemical sensors

In this work, multifunctional electrode materials based on copper-based compounds and polyaniline were applied for binder-free supercapacitors and pyrimethanil/carbendazim fungicide sensors for the first time. Brochantite and malachite were synthesized on Ni foam via a one-step solvothermal method. Polyaniline (PANI) was electrochemically polymerized as inner and outer layers. PANI as the inner layer for the brochantite/malachite@Ni foam was found to enhance conductivity and cycling stability. The composite electrodes synergistically provided a specific capacitance as high as 737 F g−1 and a capacitance retention of 83.15 % after 10,000 cycles, which are much better than each of its parent compounds. During the in-situ fabrication of supercapacitor electrode on Ni foam, the powder form of brochantite/malachite mixture was also recovered from the reaction mixture, which was then used to prepare the composite electrodes with PANI. These fabricated electrodes demonstrated superb electrochemical sensing activity for the detection of pyrimethanil and carbendazim fungicides, giving the limits of detection of 29 and 10 nM, respectively. These fungicides were successfully determined in fruits, vegetables, and water sources, yielding satisfactory recovery between 99.8 and 107.5 %. The high-performance electrochemical electrodes based on copper-based compounds developed in this study hold significant potential for a variety of electrochemical applications.

Synthetic waste derived graphitic carbon nitride (g-CN) and g-CN/carbon hybrid for supercapacitors

Synthesis of carbon-based quantum dots (QDs) from nitrogen containing organic molecules yields a large fraction of a carbonaceous byproduct composed of larger particles and flakes. While QDs are utilized in various applications, this residue is considered a waste and is thus discarded. In this work we have (i) extensively characterized the residual byproduct of autoclave-assisted solvent-free synthesis of QDs from citric acid and urea to deduce that its primary constituent is graphitic carbon nitride (g-CN), (ii) prepared a novel g-CN/ carbon (g-CN/C) hybrid material by carbonizing the crude product mixture obtained during autoclave-assisted synthesis of QDs, and (iii) performed electrochemical analysis of both g-CN and g-CN/C hybrid for supercapacitor applications. The specific capacitance of g-CN and g-CN/C at a current density of 2 A/g are 138.33 F/g and 146.67 F/g respectively, with 100 % retention of capacitance up to 5000 charge-discharge cycles. This waste-derived, N-deficit carbon nitride and its hybrid are of immediate interest for supercapacitor electrode fabrication. Their evident thermal and electrochemical properties place them among the next-generation smart materials, which are expected to compete with the incumbent technology not just in terms of electrochemical performance but also in the measures of stability, cost, and scalability.

Microwave energized preparation and electrochemical performance of Ag added NiO/CeO2ternary nanocomposites for energy storage applications

Noble metal incorporated nanocomposites are extensively useful in supercapacitor applications owing to the nature of higher specific capacity and good rate capability. We have prepared Ag added NiO/CeO2 ternary mixed oxides through green synthesis route. The influence of Ag concentration on the structural, morphological and electrochemical characteristics of NiO/CeO2 has been examined and reported. The microstructure analysis reveals that the ternary mixed oxides to consist of Ag nanoclusters, CeO2 rods and NiO flakes. The formation of ternary mixed oxides has promoted the diffusion rate of electrolyte ions resulting in superior electrochemical performance. A maximum capacity of 639 C g–1 was obtained at a current density of 2 mA cm–2 for the ternary nanocomposites containing 9 mol% of silver. Moreover, the incorporation of substantial amount of Ag has effectively improved the lifespan and reduced charge transfer resistance. The findings of the present study strongly indicate that the Ag incorporated NiO/CeO2 is a suitable candidate for supercapacitor electrode fabrication.

High-performance and low-cost coin-cell supercapacitors based on waste graphite from spent dry-cell batteries

Graphite rods extracted from spent dry-cell batteries were ground into powder and subjected to chemical activation using potassium hydroxide. The activated carbon (AC) powder showed no visible pore formation but instead appeared to have been exfoliated into thin flakes. The elemental and chemical compositions of the AC are observed to be similar to those of graphene oxide, in agreement with its surface morphology. The AC was then modified with nickel oxide (NiO) and reduced graphene oxide (rGO) and was utilized for the fabrication of supercapacitor electrodes and coin-cell supercapacitors. Increased potential window and higher overall current readings were observed in the sample with a 2:1 NiO-rGO ratio due to the redox reaction capability of NiO and fast ion transport of rGO. The electrochemical performance of the supercapacitor electrode and the coin-cell supercapacitor displayed excellent electric-double layer capacitance behavior and fast ion transfer kinetics between the electrode and electrolyte surface. The specific capacitances of the supercapacitor electrode and the coin-cell supercapacitor were determined to be 27.84 F g−1 and 20.10 F g−1, respectively, at a current density of 0.1 A g−1. The highest energy density was found to be 40.20 Wh kg−1 at a power density of 1440 W kg−1.

Fabrication of NiCo2O4@polyaniline heterostructure as positive electrode for asymmetrical supercapacitor

AbstractNiCo2O4, as a low‐cost and high‐performance binary transition metal oxide material, has been widely used in the fabrication of supercapacitor electrodes. However, the low energy density of binary metal oxides limits their large‐scale practical applications in supercapacitors, so it is highly desirable to design the structure of the NiCo2O4‐based supercapacitor. Therefore, in this paper, NiCo2O4 is compounded with polyaniline (PANI) to improve its electrochemical performance by exploiting the synergistic effect. The NiCo2O4@PANI composite electrode exhibits a specific capacitance of 561.2 F/g at 10 mV/s. In this study, asymmetric supercapacitors are assembled with NiCo2O4@PANI as the positive electrode and MXene as the negative electrode. The NiCo2O4@PANI‐CC//MXene‐CC supercapacitor has a specific capacitance of 31.95 F/g at a scan rate of 10 mV/s and a good cycle retention capacity of 86.2% after 3000 cycles. The excellent electrochemical performances are attributed to the dynamic equilibrium and fast redox kinetics of the two electrodes.

Porous Co3O4/VS4/rGO-SDBS@NF nanoflower as a high performance supercapacitor electrode

Maximizing the performance of supercapacitors requires the design of high-conductivity, stable, and cost-effective electrode materials. The current study presents a novel solution in the form of self-supporting binder-free hierarchical Co3O4/VS4/rGO-SDBS@NF composite electrodes. These electrodes are fabricated using a facile and efficient two-step hydrothermal process. The growth of Co3O4 particles on VS4/rGO-SDBS flower-shaped nanosheet arrays on nickel foam substrates results in a sufficient contraction and expansion space distribution during charge and discharge. The Co3O4/VS4/rGO-SDBS@NF composite shows a specific capacitance of 2620 F g−1 at 1 A g−1, which is significantly compared to the VS4/rGO-SDBS@NF composite at 284 F g−1 in a 6 M KOH solution. Furthermore, the as-grown electrode Co3O4/VS4/rGO-SDBS@NF composite displays excellent cycling stability, with 97.4 % of its initial capacitance retained after 5000 cycles. In summary, the utilization of a simple and accessible manufacturing and synthesis method, absence of binders, in-situ growth technique, achievement of a special morphology with effective electrochemistry, excellent supercapacitor capacity, and high cyclic stability demonstrate significant improvements compared to recent works. These results provide a new perspective for the selection and synthesis of materials and the design and fabrication of electrodes for supercapacitors as energy storage devices.

Effects of Surface Morphology with Pulse Duration Variation for Supercapacitor Electrode Fabrication Using ULPING Technique

Effects of Surface Morphology with Pulse Duration Variation for Supercapacitor Electrode Fabrication Using ULPING Technique

Aerosol derived carbon dots decorated boron nitride supported Zn-doped MoS2 for high performing flexible asymmetric supercapacitor

Alternative finding of toxic pollutant materials in proper utilization is a great challenge. Toxic and pollutant cigarette smoke having different π-conjugated organic components may work well as a precursor for carbon dots (CDs). In this work, cigarette smoke aerosol has been used for the synthesis of CDs and CDs have been further used for the fabrication of supercapacitor electrode. This methodology could be able to mitigate the two major problems-energy crisis and environment pollution. The smart combination of EDLC-type CDs deposited boron nitride (BN) and pseudocapacitive type Zn-doped MoS2 was able to enhance the supercapacitive performances. Heteroatom doping into MoS2 enhances the capacitive performances through the effective Faradic reactions. CDs and CDs deposited BN (CDs@BN) have been characterized using different characterization techniques. Zn-doped MoS2 has been uniformly grown on the CDs decorated BN (Zn–MoS2/CDs@BN) resulting in the stabilization of the electrode system. Zn–MoS2/CDs@BN nanohybrid delivered a specific capacitance (Sp.C) of 397 F/g in three-electrode system. Further, the asymmetric supercapacitor (ASC) device using Zn–MoS2/CDs@BN as cathode demonstrated wide potential range (up to 1.8 V) with a volumetric energy density of 3.42 mW h/cm3 and retaining a capacitance of ∼89% after 10,000 charging-discharging processes. Moreover, a flexible ASC device was made-up using viscous ionic electrolyte and it was able to glow a red LED, while it was bended in different angles. The methods described here will give a straightforward approach for using toxic-pollutant cigarette smoke to fabricate supercapacitor electrodes in order to compensate the upcoming energy crisis in a sustainable way.

Ice-Templated Method to Promote Electrochemical Energy Storage and Conversion: A Review

The ice-templated method (ITM) has drawn significant attention to the improvement of the electrochemical properties of various materials. The ITM approach is relatively straightforward and can produce hierarchically porous structures that exhibit superior performance in mass transfer, and the unique morphology has been shown to significantly enhance electrochemical performance, making it a promising method for energy storage and conversion applications. In this review, we aim to present an overview of the ITM and its applications in the electrochemical energy storage and conversion field. The fundamental principles underlying the ITM will be discussed, as well as the factors that influence the morphology and properties of the resulting structures. We will then proceed to comprehensively explore the applications of ITM in the fabrication of high-performance electrodes for supercapacitors, batteries, and fuel cells. We intend to find the key advances in the use of ITM and evaluate its potential to overcome the existing challenges in the development of efficient energy storage and conversion systems.

Utilization of CO2 activated litchi seed biochar for the fabrication of supercapacitor electrodes

Biochar prepared from litchi seeds was investigated for the fabrication of supercapacitor electrodes. The specific capacitance of 190 F g−1 at 1 A g−1 current density was achieved in symmetric supercapacitor fabricated using biochar obtained at 700 °C. Upon activation using CO2, the capacitance was significantly enhanced, reaching up to 493 F g−1. Moreover, the charge-discharge cyclic stability of the activated biochar supercapacitor was well maintained with capacitance retention above 90% after 10,000 charge-discharge cycles in 1 M H2SO4 electrolyte. The energy and power density of the aqueous symmetric supercapacitor prepared using activated biochar were 24.6 Wh kg−1 and 0.6 kW kg−1, respectively. Physicochemical analysis of activated biochar using BET, XRD, Raman, TEM, and XPS revealed a high surface area, hierarchical porous structure, and heteroatom rich functionalities responsible for its excellent charge storage behaviour.

X-ray photoelectron spectroscopy and temperature-dependent electrical transport properties of MnFe2O4-reduced graphene oxide nanocomposites

The reduced graphene oxide (rGO) sheets are assembled with MnFe2O4 (MFO) nanoparticles via an in-situ sol–gel autocombustion route to obtain MFO@rGO nanocomposites. The investigation of their structural and electrical properties is carried out through X-ray photoelectron spectroscopy (XPS) and impedance analyzer, respectively. XPS study discloses the presence of C, O, Fe, and Mn in the MFO@rGO composite, indicating the decoration of MnFe2O4 nanoparticles by rGO sheets. XPS study also reflects the mixed Fe3+/Fe2+ oxidation states of Fe and mixed Mn2+/Mn3+oxidation states of Mn in the composite. The highest value of ac conductivity (σac = 7.51 × 10−6 Ω−1 cm−1 at 1 MHz) at room temperature is obtained within the vicinity of the percolation threshold when rGO content is 20 wt%. The ac conductivity of composites increases with frequency up to 100 °C and then becomes independent of the frequency with a further increase in temperature. The impedance gradually decreases with temperature, revealing the occurrence of negative temperature coefficient of resistance effect in composites. The findings suggest that the MFO@rGO composites can be a potential nominee for the fabrication of electrodes for supercapacitors and flexible electronic devices of low resistance and high electrical conductivity for high-frequency applications.

High supercapacitive performance of food waste extracted activated carbon

Development of electrode materials from renewable sources is very important for reducing our dependence on non-renewable energy resources. Herein, we prepared porous structured activated carbon (AC) from food waste residue to develop a cost-effective method for fabricating carbon-based high-performance energy storage devices. Food waste-derived carbon was chemically activated using potassium hydroxide as activating agent. The as-synthesized AC was used for the fabrication of supercapacitor electrode. In the three-electrode system, it showed a maximum specific capacitance of 280 F/g at 1 A/g current density along with a good rate capability. Also, the capacitance retention was 96.1 % after 10,000 cycles, thus demonstrating an excellent cyclic stability. The energy density of the designed symmetric device was 6.7 Wh/kg with respect to a power density of 250 W/kg. The present work provided an eco-friendly, cost-effective and feasible method of designing high capacitance supercapacitor electrodes using sustainable biomass materials.

Fabrication of High‐performance Supercapacitors Using Hierarchical MnO2 Nanostructures on a Frosted Glass Surface

Supercapacitors have emerged to fill the gap between batteries and capacitors. The electrodes comprising a high surface area are utilized to fabricate the supercapacitors. However, the processes involved to fabricate electrodes are often strenuous and time‐consuming. Herein, the fabrication of high‐performance supercapacitors using frosted glass as a template to grow electrodes is reported. The frosted substrates can host much higher ions owing to the numerous surface features arising from micro‐ and nano‐level roughnesses, resulting in one order higher capacitance than the plain surface. Electrodepositing MnO2 nanostructures on the frosted surface further increases the capacitance and attains the highest value of 11 mF cm−2 at 300 min of electrodeposition, which is 6.5 times higher than the electrodes without MnO2. The stacked supercapacitors are made using polyvinyl alcohol/H2SO4 gel electrolyte, and the devices exhibit superior electrochemical properties such as high scan rate stability (100 V s−1), high cut‐off frequency (333 Hz), low iR drop, high cyclic stability (93% capacitance retention after 10 000 cycles), and low self‐discharge. The roughened nature of the frosted glass can be imprinted onto the surface of polydimethylsiloxane substrate to fabricate flexible and stretchable supercapacitors. The present work can pave the way for facile and low‐cost fabrication of supercapacitor electrodes.

Agarose Gel-Templating Synthesis of a 3D Wrinkled Graphene Architecture for Enhanced Supercapacitor Performance.

The increasing use of rapidly fluctuating renewable energy sources, such as sunlight, has necessitated the use of supercapacitors, which are a type of energy storage system with high power. Chemically exfoliated graphene oxide (GO) is a representative starting material in the fabrication of supercapacitor electrodes based on reduced GO (rGO). However, the restacking of rGO sheets driven by π–π stacking interactions leads to a significant decrease in the electrochemically active surface area, leading to a loss of energy density. Here, to effectively inhibit restacking and construct a three-dimensional wrinkled structure of rGO (3DWG), we propose an agarose gel-templating method that uses agarose gel as a soft and removable template. The 3DWG, prepared via the sequential steps of gelation, freeze-drying, and calcination, exhibits a macroporous 3D structure and 5.5-fold higher specific capacitance than that of rGO restacked without the agarose template. Further, we demonstrate a “gel-stamping” method to fabricate thin-line patterned 3DWG, which involves the gelation of the GO–agarose gel within micrometer-sized channels of a customized polydimethylsiloxane (PDMS) mold. As an easy and low-cost manufacturing process, the proposed agarose gel templating method could provide a promising strategy for the 3D structuring of rGO.

Evaporation-induced hydrated graphene/polyaniline/carbon cloth integration towards high mass loading supercapacitor electrodes

The convenient fabrication of supercapacitor electrodes with high active material mass loading is of great significance to the practical application. In this paper, a novel and efficient strategy is proposed to prepare graphene/polyaniline (PANI) composite with controllable mass loading towards high-performance supercapacitor electrodes. The graphene oxide (GO)/PANI colloid layer is drop-coated onto carbon cloth (CC) before evaporating most of the water. The as-obtained hydrated GO/PANI/CC film undergoes a facile hydrazine reduction treatment and yields the porous reduced GO (rGO)/PANI active layer fixed on the CC current collector, which could directly act as the binder-free supercapacitor electrode. As a result, the excellent adhesion of active layer with CC and the uniform PANI distribution on porous rGO matrix contribute greatly to the fast electron and ion transport in the electrochemical activities. The integrated rGO/PANI/CC electrode achieves a high specific capacitance of 871.5 F g−1 at the current density of 1.5 A g−1 with superior rate performance. More importantly, repeating the drop-coating/water-evaporating process could conveniently realize the high rGO/PANI mass loading (up to 10 mg cm−2) on the current collector. The corresponding symmetric all-solid-state supercapacitors with different mass loadings can deliver the maximum energy densities of 39.1 Wh kg−1, 425.3 μWh cm−2, and 4.0 mWh cm−3, manifesting their promising practical prospect. This work would provide a new path for the fabrication of graphene-based supercapacitor electrodes and other functional film materials.