Pseudocapacitive Energy Storage Research Articles

Boosting of Redox-Active Polyimide Porous Organic Polymers with Multi-Walled Carbon Nanotubes towards Pseudocapacitive Energy Storage.

Redox-active porous organic polymers (POPs) demonstrate significant potential in supercapacitors. However, their intrinsic low electrical conductivity and stacking tendencies often lead to low utilization rates of redox-active sites within their structural units. Herein, polyimide POPs (donated as PMTA) are synthesized in situ on multi-walled carbon nanotubes (MWCNTs) from tetramino-benzoquinone (TABQ) and 1,4,5,8-naphthalene tetracarboxylic dianhydride (PMDA) monomers. The strong π-π stacking interactions drive the PMTA POPs and the MWCNTs together to form a PMTA/MWCNT composite. With the assistance of MWCNTs, the stacking issue and low conductivity of PMTA POPs are well addressed, leading to the obvious activation and enhanced utilization of the redox-active groups in the PMTA POPs. PMTA/MWCNT then achieves a high capacitance of 375.2 F g-1 at 1 A g-1 as compared to the pristine PMTA POPs (5.7 F g-1) and excellent cycling stability of 89.7% after 8000 cycles at 5 A g-1. Cyclic voltammetry (CV) and in situ Fourier-Transform Infrared (FT-IR) results reveal that the electrode reactions involve the reversible structural evolution of carbonyl groups, which are activated to provide rich pseudocapacitance. Asymmetric supercapacitors (ASCs) assembled with PMTA/MWCNTs and activated carbon (AC) offer a high energy density of 15.4 Wh kg-1 at 980.4 W kg-1 and maintain a capacitance retention of 125% after 10,000 cycles at 5 A g-1, indicating their good potential for practical applications.

Advancements in Asymmetric Supercapacitors: From Historical Milestones to Challenges and Future Directions.

Numerous challenges, like the uninterrupted supply of electricity, stable and reliable power, and energy storage during non-operational hours, arise across various industries due to the absence of advanced energy storage technologies. With the continual technological advancements in portable electronics, green energy, and transportation, there are inherent limitations in their innovative production. Thus, ongoing research is focused on pursuing sustainable energy storage technologies. An emerging solution lies in the development of asymmetric supercapacitors (ASCs), which offer the potential to extend their operational voltage limit beyond the thermodynamic breakdown voltage range of electrolytes. This is achieved by employing two distinct electrode materials, presenting an effective solution to the energy storage limitations faced by ASCs. The current review concentrates on the progression of working materials to develop authentic pseudocapacitive energy storage systems (ESS). Also, evaluates their ability to exceed energy storage constraints. It provides insights into fundamental energy storage mechanisms, performance evaluation methodologies, and recent advancements in electrode material strategies. The review approaches developing high-performance electrode materials and achieving efficient ASC types. It delves into critical aspects for enhancing the energy density of ASCs, presenting debates and prospects, thereby offering a comprehensive understanding and design principles for next-generation ASCs in diverse applications.

Imine-Linked π-Conjugated Covalent Organic Frameworks as an Efficient Electrode Material for Pseudocapacitive Energy Storage

Imine-Linked π-Conjugated Covalent Organic Frameworks as an Efficient Electrode Material for Pseudocapacitive Energy Storage

A Cross-linked n-Type Conjugated Polymer with Polar Side Chains Enables Ultrafast Pseudocapacitive Energy Storage.

Pseudocapacitors bridge the performance gap between batteries and electric double-layer capacitors by storing energy via a combination of fast surface/near-surface Faradaic redox processes and electrical double-layer capacitance. Organic semiconductors are an emerging class of pseudocapacitive materials that benefit from facile synthetic tunability and mixed ionic-electronic conduction. Reported examples are mostly limited to p-type (electron-donating) conjugated polymers, while n-type (electron-accepting) examples remain comparatively underexplored. This work introduces a new cross-linked n-type conjugated polymer, spiro-NDI-N, strategically designed with polar tertiary amine side chains. This molecular design aims to synergistically increase the electroactive surface area and boost ion transport for efficient ionic-electronic coupling. Spiro-NDI-N demonstrates excellent pseudocapacitive energy storage performance in pH-neutral aqueous electrolytes, with specific capacitance values of up to 532 F g-1 at 5 A g-1 and stable cycling over 5000 cycles. Moreover, it maintains a rate capability of 307 F g-1 at 350 A g-1. The superior pseudocapacitive performance of spiro-NDI-N, compared to strategically designed structural analogues lacking either the cross-linked backbone or polar side chains, validates the essential role of its molecular design elements. More broadly, the design and performance of spiro-NDI-N provide a novel strategy for developing high-performance organic pseudocapacitors.

Supramolecular Engineering of Ti3C2Tx MXene -Perylene Diimide Hybrid Electrodes for the Pseudocapacitive Electrochemical Storage of Calcium Ions.

The rare combination of metallic conductivity and surface redox activity enables 2D MXenes as versatile charge storage hosts for the design of high-rate electrochemical energy storage devices. However, high charge density metal ions including but not limited to Ca+2 and Mg+2 pose challenges such as sluggish solid-state diffusion and also inhibiting the charge transfer across electrode-electrolyte interfaces. In this work, free-standing hybrid electrode architectures based on 2D titanium carbide-cationic perylene diimide (Ti3C2Tx@cPDI) via supramolecular self-assembly are developed. Secondary bonding interactions such as dipole-dipole and hydrogen bonding between Ti3C2Tx and cPDI are investigated by zeta potential and Fourier-transformed infrared (FTIR) spectroscopy . Ti3C2Tx@cPDI free-standing electrodes show typical volumetric capacitance up to 260 F cm-3 in Mg2+ and Ca2+ aqueous electrolytes at charging times scales from 3minutes to a few seconds. Three-dimensional (3D) Bode maps are constructed to understand the charge storage dynamics of Ti3C2Tx@cPDI hybrid electrode in an aqueous Ca-ion electrolyte. ,Pseudocapacitance is solely contributed by the nanoscale distribution of redox-active cPDI supramolecular polymers across 2D Ti3C2Tx. This study opens avenues for the design of a wide variety of MXene@redox active organic charge hosts for high-rate pseudocapacitive energy storage devices.

(Digital Presentation) Electrospun N-Doped CNFs Embedded Metal Oxides with Improved Graphitization for Superior Pseudocapacitive Energy Storage

One-dimensional carbon nanofibers (CNFs) based pseudocapacitive hybrid electrodes are the next step forward in achieving highly efficient supercapacitor(SCs) electrodes. However, it is still a paramount challenge to develop rationally designed CNFs with sufficient pseudocapacitive surface functionalities, and adequate porosity via a facile synthesis for better practical applicability. Herein, we are reporting a single-step electrospinning methodology followed by carbonization to generate a unique spatial 1D structure with metal oxide (MO) particles embedded in CNFs (M-CNFs). By optimizing the polymer ratio with that of MO, it was possible to obtain an in-situ N-enriched porous CNF network generating a predominant pseudocapacitive charge-storing mechanism. The resulting material is a synergistic combination of MOs, and surface-enriched N-CNFs with good electrical properties and high surface area, suitable to be employed as electrodes for SCs. A deep investigation of the M-CNFs properties has been performed to understand the physical characteristics of the hybrid MO/CNFs material. Further, a flexible symmetric SC device exploiting the polymeric gel-based (PVA+ H2SO4) electrolyte was assembled delivering a maximum energy density of up to 50 Wh Kg-1 and capacitance retention of 90% with a coulombic efficiency of 95%, enabling both electric double-layer and pseudo-capacitance behaviors. The resulting performances of the here-proposed material allow the prediction of the enormous potentialities of these flexible energy-storage devices for industrial-scale application. Keywords: surface N enrichment, electrospinning, hybrid CNFs, flexible symmetric supercapacitors.

Cobalt-Nickel Layered Double Hydroxides on Electrospun MXene for Superior Asymmetric Supercapacitor Electrodes.

Flexible electrodes for energy storage and conversion require a micro-nanomorphology and stable structure. Herein, MXene fibers (MX-CNF) are fabricated by electrospinning, and Co-MOF nanoarrays are prepared on the fibers to form Co-MOF@MX-CNF. Hydrolysis and etching of Co-MOF@MX-CNF in the Ni2+ solution produce cobalt-nickel layered double hydroxide (CoNi-LDH). The CoNi-LDH nanoarrays on the MX-CNF substrate have a large specific surface area and abundant electrochemical active sites, thus ensuring effective exposure of the CoNi-LDH active materials to the electrolyte and efficient pseudocapacitive energy storage and fast reversible redox kinetics for enhanced charging-discharging characteristics. The CoNi-LDH@MX-CNF electrode exhibits a discharge capacity of 996 F g-1 at a current density of 1 A g-1 as well as 78.62% capacitance retention after 3,000 cycles at 10 A g-1. The asymmetric supercapacitor (ASC) comprising the CoNi-LDH@MX-CNF positive electrode and negative activated carbon electrode shows an energy density of 48.4 Wh kg-1 at a power density of 499 W kg-1 and a capacity retention of 78.9% after 3,000 cycles at a current density of 10 A g-1. Density-functional theory calculations reveal the charge density difference and partial density of states of CoNi-LDH@MX-CNF confirming the large potential of the CoNi-LDH@MX-CNF electrode in energy storage applications.

Intercalation of Hydrogen in Perovskite Oxide for Pseudocapacitive Energy Storage

Intercalation of Hydrogen in Perovskite Oxide for Pseudocapacitive Energy Storage

Enhancing pseudocapacitive energy storage system performance with electrodeposited CuSx and CoSx biphasic transitional metal sulfide (TMS) based nanostructured electrode on nickel foam

This study investigated the pseudocapacitive energy storage system of biphasic CuSx and CoSx electrodeposited on nickel foam (NF). XRD, FESEM, and EDX show the formation of nano-flower-shaped biphasic layer on NF. The biphasic electrode shows higher areal specific capacitance (Csp) than the single-layered NF/CuSx and NF/CoSx electrodes. The Csp of the NF/CuSx/CoSx drops by 42 % as the scan rate (ϑ) rises from 5 mV s−1 to 20 mV s−1. Electrode polarization and reduced ion migration occurring with rapid scan rates are responsible for this decrement. Galvanostatic charge-discharge (GCD) analysis showed that Csp declined from 11.42 to 9.63 F cm−2, and the retained Csp was 84 % as the current density shifted from 4 to 8 mA cm−2. The energy density of 0.30 mWh.cm−2 and power density of 1.57 mW cm−2 imply significant energy storage capability of the electrode. The kinetic analysis indicates that 78 % of the capacitance is diffusion-controlled process in the NF/CuSx/CoSx electrode. The b-value of around 0.7 suggests that the pseudocapacitance mostly originates from diffusion-controlled processes. The poor cyclic stability of NF/CuSx/CoSx was demonstrated by only upholding 61 % of its original Csp after 500 cycles. However, the higher coulombic efficiency indicates that a greater proportion of the electrical charge is stored in the supercapacitor. The study explores the biphasic design of copper and cobalt sulphide-based electrodes as potential pseudocapacitive energy storage system applications such as supercapacitors and supercapatteries.

Proton is Essential or Not: A Fresh Look on Pseudocapacitive Energy Storage of PANI Composites.

Protonation has been considered essential for the pseudocapacitive energy storage of polyaniline (PANI) for years, as proton doping in PANI chains not only activates electron transport pathways, but also promotes the proceeding of redox reactions. Rarely has the ability for PANI of storing energy without protonation been investigated, and it remains uncertain whether PANI has pseudocapacitive charge storage properties in an alkaline electrolyte. Here, this work first demonstrates the pseudocapacitive energy storage for PANI without protonation using a PANI/graphene composite as a model material in an alkaline electrolyte. Using in situ Raman spectroscopy coupled with electrochemical quartz crystal microbalance (EQCM) measurements, this work determines the formation of -N= group over potential on a PANI chain and demonstrates the direct contribution of OH- in the nonprotonation type of oxidation reactions. This work finds that the PANI/graphene composite in an alkaline electrolyte has excellent cycling stability with a wider operation voltage of 1V as well as a slightly higher specific capacitance than that in an acidic electrolyte. The findings provide a new perspective on pseudocapacitive energy storage of PANI-based composites, which will influence the selection of electrolytes for PANI materials and expand their application in energy storage fields.

Ti3C2Tx MXene as a growth template for amorphous RuOx in carbon nanofiber-based flexible electrodes for enhanced pseudocapacitive energy storage

A noble surface engineering method was developed to create a binder-free flexible electrode comprising Ti3C2Tx MXene/carbon nanofibers (MCNFs) covered by amorphous RuOx with a combined electrospinning and hydrothermal process. Utilizing the hydrophilicity of the MXene on/in the MCNFs, RuOx was easily coated on the surfaces of the MCNFs through oxygen-mediated chemical bonding between the functional groups of the MXene and Ru ions. A structural analysis revealed that the MXene acted as a growth template for RuOx and that the formed RuOx had an amorphous and disordered state in the composite electrode, which impacted the electrochemical performance. The electrochemical tests showed that these composite electrodes improved the electrochemical performance, with a two-fold increase in the gravimetric capacitance (279.4 F/g at 2 mV/s) relative to that of pristine MCNFs, a wide potential window (from 0.7 to 1 V) providing a superior energy density of 8.5 Wh/kg at a power density of 85.8 W/kg, as well as long-term cycling stability (99% after 10,000 cycles). The synergetic effect of the RuOx and MXene in the composite electrodes was attributed to an enhanced pseudocapacitive reaction. Our novel electrodes and fabrication method confirm the great potential of CNF-based composites for the development of high-performance binder-free electrodes for supercapacitors.

Spintronic State‐Induced Interface Reconfiguration of 2H‐Perovskite Related Oxides for Pseudocapacitance Increase

AbstractPerovskite oxides are able to realize pseudocapacitive energy storage through oxygen anion intercalation. Herein, it is demonstrated that, based on the three 2H‐perovskite related oxides Sr6Co5O15‐x, Sr5Co4O12‐x, and Sr5Co3NiO12‐x as the research objects, metal oxyhydroxides generated through surface reconfiguration during electrochemical processes can contribute extra capacity besides the oxygen‐anion intercalation. This is because the electron spin state controlled by the transition metal valence state in the pseudo trigonal prisms for the 2H‐perovskite structure will affect the Jahn–Teller (JT) distortion. The strong JT distortion of Co2+ and Ni3+ would elongate metal‐O bonds, thereby helping the formation of metal oxyhydroxides on the surface of the pristine material. Among the three 2H‐perovskite related oxides, the specific capacity of Sr5Co3NiO12‐x having the most Co2+ and Ni3+ contents showed the highest capacity increase. This study will provide a promising pathway to develop advanced perovskite‐like oxide pseudocapacitive materials.

Series of Halogen Engineered Ni(OH)2 Nanosheet for Pseudocapacitive Energy Storage with High Energy Density.

Ni(OH)2 nanosheet, acting as a potential active material for supercapacitors, commonly suffers from sluggish reaction kinetics and low intrinsic conductivity, which results in suboptimal energy density and long cycle life. Herein, a convenient electrochemical halogen functionalization strategy is applied for the preparation of mono/bihalogen engineered Ni(OH)2 electrode materials. The theoretical calculations and experimental results found that thanks to the extraordinarily high electronegativity, optimal reversibility, electronic conductivity, and reaction kinetics could be achieved through F functionalization . However, benefiting from the largest ionic radius, INi(OH)2 contributes the best specific capacity and morphology transformation, which is a new finding that distinguishes it from previous reports in the literature. The exploration of the interaction effect of halogens (F, INi(OH)2 , F, BrNi(OH)2 , and Cl, INi(OH)2 ) manifests that F, INi(OH)2 delivers a higher specific capacity of 200.6 mAh g-1 and an excellent rate capability of 58.2% due to the weaker electrostatic repulsion, abundant defect structure, and large layer spacing. Moreover, the F, INi(OH)2 //FeOOH@NrGO device achieves a high energy density of 97.4Wh kg-1 and an extremely high power density of 32426.7W kg-1 , as well as good cycling stability. This work develops a pioneering tactic for designing energy storage materials to meet various demands.

Halogen chlorine triggered oxygen vacancy-rich Ni(OH)2 with enhanced reaction kinetics for pseudocapacitive energy storage

Two-dimensional (2D) Ni(OH)2 nanosheets can theoretically expose their active sites of 100%. Whereas, their intrinsic easy accumulation and low conductivity lead to weak and unsustainable reaction kinetics. Herein, we propose a novel halogen chlorine-triggered electrochemical etching strategy to controllably manage the reaction kinetics of 2D Ni(OH)2 nanosheets (EE/Cl-Ni(OH)2). It is found that halogen chlorine doping can adjust the interlamellar spacing flexibly and promote the lattice oxygen activation to achieve controlled construction of superficial oxygen defects at the adjustable voltage. The optimal EE/Cl-Ni(OH)2 electrode exhibits a high rate capability and excellent specific capacity of 206.9 mA h g−1 at 1 A g−1 in a three-electrode system, which is more than twice as high as the pristine Ni(OH)2. Furthermore, EE/Cl-Ni(OH)2 cathode and FeOOH@rGO anode are employed for developing an aqueous Ni-Fe battery with an excellent energy density of 83 W h kg−1, a high power density of 17051 W kg−1, and robust durability over 20,000 cycles. This strategy exploits a fresh channel for the ingenious fabrication of high-efficiency and stable nickel-based deficiency materials for energy storage.

Exploring the origin of pseudocapacitive energy storage differences for molybdenum nitride-based electrodes

Molybdenum nitride-based materials have been extensively investigated as pseudocapacitive materials due to their superior metallic conductivity and thermal stability. Nevertheless, few studies have focused on the origin of pseudocapacitance (Credox) differences for charged molybdenum nitride electrodes with different crystal structures. Herein, taking cubic Mo2N (NaCl-type), Mo3N2 (CsCl-type) and hexagonal MoN (AlB2-type) as the research targets, we have systematically investigated the differences in rate performance and capacitance of these three materials by experimental methods and density functional theory (DFT) calculations to obtain the origin of Credox differences among them. DFT calculations prove that the proportions of Credox are 86.45%, 85.32% and 84.57% for Mo2N, Mo3N2 and MoN and thus the Mo2N features the most obvious pseudocapacitive behavior. Furthermore, the rigid band approximation (RBA) method reveals that the differences of work function change (ΔWF) are the root cause of Credox differences for these three kinds of charged materials. The highest electrochemical capacitance retention, highest conductivity, and fastest K+ ion mobility indicate that the MoN possesses the best rate performance among these three materials. Additionally, the most intact nanowire morphology and smallest ΔWF of Mo2N enable it to possess the highest electrochemical capacitance and theoretical total capacitance (Ctotal). The above findings will shed light on examining capacitance in a charged environment while screening the next-generation high-performance pseudocapacitive materials under various crystal structures.

Hierarchical MnO2/NiS–MnS with Rich Electro-Microstructural Physiognomies for Highly Efficient All-Solid-State Hybrid Supercapacitors

To revolutionize the charge storage efficiency of electrode materials for their utilizations in high Ragone efficient electrochemical energy storage devices, herein, a slow-precipitation-induced material growth approach has been innovated to design a hetero oxide–sulfide [MnO2/NiS–MnS (MnO2/Ni–Mn–S)] material with smaller crystallite size, ultrathin assembled-sheet-like microstructure, and perceptible phase physiognomies (α-MnO2, MnS, and α-NiS). The electroredox assessment of MnO2/Ni–Mn–S illustrates high pseudocapacitive energy storage efficiency, significant redox reversibility, lowly constrained bulk accessibility of the OH– ions at higher rate electrochemical reaction conditions, dominance of semi-infinite diffusion-controlled electrochemical processes, and extremely low charge-transfer resistance (∼1.45 Ω), total series resistance (∼0.51 Ω) and diffusion (Warburg) resistance. A fabricated 1.8 V MnO2/Ni–Mn–S||nitrogen-doped reduced graphene oxide (N-rGO) all-solid-state hybrid supercapacitor (ASSHSC) device with N-rGO as the negative electrode material delivers high area and mass specific capacitance/capacity, ∼100% Columbic efficiency at high-rate operating conditions, and very low charge-transfer and Warburg resistance. The MnO2/Ni–Mn–S||N-rGO ASSHSC device also delivers excellent Ragone efficiency (ED = 31.5 W h kg–1 at PD = 937.5 W kg–1 and ED = 15.5 W h kg–1 at PD = 2767.5 W kg–1) and ∼97.6% retention of charge storage after 11,000 uninterrupted charge–discharge cycles. The significantly improved supercapacitive charge storage efficacy of MnO2/Ni–Mn–S is ascribed to the cohesive redox activity of Ni2+, Ni3+, Mn2+, and Mn3+ and nonstoichiometric Ni2±δ, Ni3±δ, Mn2±δ, and Mn3±δ ions, rich ion-disseminating bulk, S2– vacancy-induced electronic conductivity, and suitable electro-microstructural physiognomies for the electrochemical processes.

Structure Effect on Pseudocapacitive Properties of A2LaMn2O7 (A = Ca, Sr)

Herein, the effect of structure on pseudocapacitive properties in alkaline conditions is demonstrated through the investigation of isoelectronic oxides Ca2LaMn2O7 and Sr2LaMn2O7, where the difference in ionic radii of Ca2+ and Sr2+ leads to a change in structure and lattice symmetry, resulting in an orthorhombic Cmcm structure for the former and a tetragonal I4/mmm structure for the latter. While calcium and strontium do not make a direct contribution to the near‐surface faradaic processes that are essential to the pseudocapacitive properties, their effect on the structure leads to a change in the oxygen intercalation process and the associated pseudocapacitive energy storage. It is shown that Sr2LaMn2O7 has a significantly greater specific capacitance than Ca2LaMn2O7. In addition, the former shows a considerably higher‐energy density compared to the latter. Furthermore, these materials show highly stable energy‐storage properties, and retain their specific capacitance over 10 000 cycles of charge–discharge in a symmetric pseudocapacitive cell. Importantly, these findings show the structure–property relationships, where a change in the structure and lattice symmetry can result in a significant change in pseudocapacitive charge–discharge properties in isoelectronic systems.

Lattice strain induced d-band centre engineering enabled pseudocapacitive energy storage in 2D hypo-hyper electronic V-NiCo2O4 for asymmetric supercapacitors.

Understanding the role of fundamental structural engineering of materials in unravelling the underlying rudimentary electronic structure-dependent charge storage mechanisms is crucial for developing new strategic approaches toward high-performance electrochemical energy storage devices. Here, we demonstrate the role of strain engineering by V doping-induced lattice contraction in NiCo2O4 for increasing the energy density and power density of aqueous asymmetric hybrid supercapacitors. For application in energy storage, we demonstrate the influence of electron-deficient V4+/5+ doping in electron-rich Ni2+ sites, which has been found to result in the formation of a hypo-hyper electronically coupled cation pair causing a shift in the d-band and O 2p band centres and distortion of CoO6 octahedra. Optimization of V doping to 3 mol%, achieved by a binder-free one-step hydrothermal method, has yielded a 96% increase in specific capacitance of up to 2316 F g-1 from 1193 F g-1 in pristine materials at 1 A g-1 in a three-electrode configuration with a coulombic efficiency (η%) of 94% and a 24% increase in rate capacity. A two-fold increase in specific capacitance in the pouch cell device, fabricated with a functionalized carbon nanosphere positive electrode, has been observed for the V-doped samples at 1 A g-1 with a η% of 97% and a maximum energy density of 96.3 W h g-1 and a maximum power density of 8733.6 W g-1 which are 41% and 24.3% higher than the pristine device, respectively. Excellent cycling stability of 95.4% capacitance retention has been observed after 6000 cycles. DFT calculations have been carried out to understand the previously unexplored effect of lattice strain on charge transport and quantum capacitance, and ultimately its effect on the transition state kinetics of energy storage faradaic reaction mechanisms. The aim of this work is to establish a fresh perspective on developing a deep understanding of the fundamental electronic and structural properties of materials by drawing in concepts from descriptor models in electrocatalysis to reveal the role of lattice strain and d-band centre tailoring in enabling pseudocapacitive energy storage.

Organic materials as charge hosts for pseudocapacitive energy storage

Organic materials employ earth-abundant elements as the basic constituents, which makes organic energy storage devices sustainable and cost-effective.

What about electrochemical behaviors for aurivillius-phase bismuth tungstate? Capacitive or pseudocapacitive.

Researchers mainly explore the mechanism of pseudocapacitance through studying electrode materials with Faraday pseudocapacitive behavior. Here, we found that Bi2WO6, a typical Aurivillius phase material with pseudo-perovskite structure, showed nearly ideal pseudocapacitive behavior. The cyclic voltammetry curve is approximately rectangular in shape, with no redox peaks, which is similar to that of carbon materials. And the shape of the galvanostatic charge-discharge curve is close to an isosceles triangle. In addition, the kinetic analysis demonstrated that the electrochemical process of the A-Bi2WO6 electrode is dominated by surface processes, not diffusion. The A-Bi2WO6 electrode material presents a great volumetric specific capacitance of 466.5 F cm-3 at 0.5 A g-1. These electrochemical properties confirm that the Bi2WO6 material can serve as an ideal support material to explore pseudocapacitive energy storage. This work also provides guidance for the development of new pseudocapacitive materials.