Capacitive Properties Research Articles

Electrochemical investigation of β-MnO2 octahedral microparticles decorated micro-sized silicon

Charge storage study using β-MnO2 octahedrons has not been studied due to its relatively lower capacitive property. This work presents the charge storage capacity of truncated β-MnO2 octahedral microparticles decorated onto micro-sized silicon (mSi) prepared by simple cost-effective and environment-friendly hydrothermal method. The designed truncated MnO2 octahedrons- mSi observed through SEM, when structurally characterized using XRD and Raman spectroscopy revealed the β phase of MnO2. The 3-electrode cell-based charge storage study demonstrated a specific capacitance of 353 F g−1 at 5 mV s−1 with an equivalent series resistance (ESR) of 10.29 ohms. The CV curves revealed a pseudocapacitive charge storage behavior with reversible Faradaic reactions and confirmed through charge storage kinetics evaluation using power law. An attractive energy density of 97.75 Wh kg−1 and 1700 W kg−1 power density was displayed by the electrode at 1.7 A g−1 current density which is comparable to existing literature in the field. This study not only opens the possibility of exploring the practical applicability of the enhanced charge storage capability using the proposed design but also stimulates further research on doped β-MnO2 with suitable conductive material to reduce ESR. In addition, the role of mSi can be further explored to provide enhanced energy storage applications.

Optimizing performance: Achieving high capacitance and cycling durability in alkaline electrolyte with SnO2/SnSe||AC/KOH-based aqueous hybrid supercapacitor

A facile wet-chemical assisted synthesis route is adapted to prepare a novel SnO2/SnSe nanocomposite for the time to construct an aqueous asymmetric hybrid supercapacitor (AAHSC). The detailed characterization reveals the appropriate formation of micro flower-like SnO2-SnSe nanocomposite-covered with SnSe network to provide a conductive support and facilitate charge transport during the electrochemical processs. Compared with pure SnO2 micro flowers and SnSe electrodes, the SnO2-SnSe nanocomposite electrode delivers a brilliant charge storage performance. A rapid charge transport pathways was accomplished due to the lowest charge transfer resistance, resulting in a high capacitance and improved charge storage properties in an aqueous alkaline electrolyte solution with incredible reversibility and rate capability. Inspired by the excellent charge storage and capacitive properties, a two-cell mode-based AAHSC was built with SnO2-SnSe nanocomposite (cathode) and activated carbon (AC) as an anode (symbolized as SnO2-SnSe||AC/KOH) displayed the highest energy of 33.4 Wh/kg at a maximum power of 4003.7 W/kg, operating in a voltage of 1.6 V with excellent cycling stability of 89.5 %.

A mixed dual-ion electrolyte for high-rate performance and remarkable cycling stability of NaMnO2 in hybrid supercapacitors

Recently, pre-sodiated manganese oxides are gaining more attention due to their higher specific capacitance and better cycling stability compared to pristine manganese oxides. However, previous reports on their electrochemical performances are limited to the aqueous electrolytes of Na+ and K+ ions. In this study, the electrochemical capacitance properties of hydrothermally synthesized NaMnO2 are investigated in aqueous electrolytes of 0.5 M NaNO3, 0.5 M Mg(NO3)2, and the mixed dual-ion electrolyte of 0.5 M NaNO3 and 0.25 M Mg(NO3)2. Although 0.5 M Mg(NO3)2 enables a higher specific capacitance of 427 F g−1 compared to that of 267 F g−1 in NaNO3 electrolyte, both electrolytes provide limited rate capability. On the other hand, the mixed dual-ion electrolyte of 0.5 M NaNO3+0.25 M Mg(NO3)2 enables highly improved rate capability along with a high specific capacitance of 325 F g−1, signifying the importance of the mixed dual-ion electrolyte for optimizing the specific capacitance and the high-rate capability of NaMnO2. An aqueous hybrid supercapacitor of activated carbon||NaMnO2 demonstrates excellent cycling stability of 98.9 % capacitance retention in the mixed electrolyte as compared to 96.9 % in NaNO3 electrolyte after 6000 cycles.

Tungsten doping role in structural modification and boosting electrochemical efficiency of Co(OH)2 dandelion assemblies

Globally increasing energy demands and the drastic climate changes are pursuing cost-effective and environmental friendly energy storage option i.e. supercapacitors. Tungsten (W) doping in Co(OH)2 has played an effective role in morphology changes along with improving its super capacitive properties. The 5 % W-doped Co(OH)2 revealed perfectly dandelion assemblies having size range 3–4 µm and emerging wires with ∼10 nm diameter. These dandelion assemblies exhibited pseudocapacitive behavior and excellent specific capacitance 1000 Fg−1 at 1Ag−1 and 1051 Fg−1 at 5mVs−1 which is more than twice as compared to pristine Co(OH)2. Power law (b = 0.71) exhibited capacitive nature of 5 % W-doped Co(OH)2. High cyclic stability with 92 % charge retention have been achieved for 5000 cycles. This improved electrochemical performance is attributed to the high surface area with numerous active sites, amazing Faradaic redox reactions and excellent charge transfer rate. Hence, 5 % W-Co(OH)2 dandelion assemblies are promising electrode materials for efficient supercapacitors.

High-performance CF/MXene/β-PbO2 materials as anodes for asymmetric supercapacitors

MXene has excellent capacitive properties as a two-dimensional material, but its cycling stability is poor. β-PbO2 is one of the common crystalline forms of lead dioxide, and it has excellent electrochemical properties and cyclic stability and has potential as a capacitor electrode material. However, the capacitive performance of β-PbO2 as a capacitor electrode material is not ideal. Therefore, CF/MXene/β-PbO2 (CMP) composites were prepared in this study by combining β-PbO2 with CF/MXene (CM) using a constant current electrodeposition method, and their electrochemical energy storage properties were investigated. The ordered structure of interwoven CF is used to fix MXene, which has metallic properties and large layer spacing, as the matrix material. This utilization enables faster ion transport and electron storage. The electrochemical advantages of β-PbO2 and CM can be unified by the synergistic effect of the composites, which results in a high specific capacity (399.42 F g−1) of the CMP electrode at 0.2 A g−1. In addition, the CM//CMP asymmetric supercapacitor constructed in 1 M Na2SO4 solution has a wide potential window of 2.0 V and a high specific capacitance of 193.8C g−1, and the capacity remains 54.3% of the initial value after 5000 cycles at a charge/discharge rate of 40 mA g−1. This work provides important research ideas and clues for the application of β-PbO2 composite electrode materials in supercapacitors.

ANALYSIS OF BUILDING A FACIES MODEL OF A RESERVOIR USING THE RESULTS OF INTERPRETATION OF SEISMIC DATA

Forecasting changes in the characteristics of sediment properties is an urgent task at all stages of exploration and development of deposits. Remote sensing techniques for sediment research, such as seismic surveys, are now becoming a prerequisite for a full study of the study area. The problems that need to be solved are not limited to the construction of a structural-tectonic model. It is necessary to look for opportunities to predict filtration and capacitance properties (PP) in the interwell space. This will improve the quality of forecasting reservoir development zones for complex reservoirs, which will result in optimization of production drilling and reduction in the risks of drilling unproductive wells. The deposits considered in this work are represented by terrigenous sediments. When developing oil-saturated intervals, water and gas breakthroughs are expected, which are especially typical for high-permeability intervals. The commercial characteristics of sediments depend on many factors, including formation conditions. Knowledge of the sedimentation environment greatly facilitates the task of predicting reservoir rocks at all stages of field development.The paper presents the results of constructing a facies model using the results of inversion transformations of seismic surveys and interpretation of GIS (geophysical surveys in wells). When creating a facies distribution model, a probabilistic assessment of the presence of a particular facies in the study area was used.In previous works, the facies model was accepted conceptually. Its influence on the final geological model and assessment of hydrocarbon reserves was indirect. The facies model presented in the article does not conceptually contradict the previously accepted one. That is, the concept of sediment formation has been preserved, but its influence on the geological model has changed. This allows you to more accurately display the geological structure of layers and optimize technological solutions when developing an operational facility.After the work was completed, more than thirty-five wells were drilled. Based on the results of the assessment of new wells, the percentage of confirmation of the forecast of facies distribution along the wellbore with the actual data of new drilling (facies identification according to GIS data) is more than 60–65 % for the entire study area.

Reactive force field potential with shielded long-range Coulomb interaction: Application to graphene–water capacitors

Electrode–electrolyte interfacial properties characterize the functioning of electrochemical devices, and reactive molecular dynamics simulations, using reactive force fields (ReaxFF) and charge equilibration (QEq) techniques, are classical atomistic methods for investigating the processes that govern the device properties. However, the numerical implementation of ReaxFF and QEq treats Coulomb interaction with a short-distance cutoff for computational speed, thereby limiting interactions among atoms to a domain containing only their neighbor lists. Excluding long-distance Coulomb interactions makes the description of electrostatics in large-scale systems intractable. We apply Ewald sum in the extension of ReaxFF to include long-range Coulomb (LRC) interactions and investigate the effect of the inclusion on the electrostatic and capacitive properties of graphene–water interfaces at different applied potentials in comparison with the original ReaxFF. The study shows that with the inclusion of long-range Coulomb, the capacitance amounts to 4.9 ± 0.2 μF cm−2 compared with 4.4 ± 0.2 μF cm−2 predicted by the original ReaxFF [with short-range Coulomb (SRC)]; thus, indicating that SRC underestimates the capacitance of water between graphene walls by 12% when compared with the 5.0 μF cm−2 predicted with the extended simple point charge (SPC/E) water model. Thus, the results indicate that LRC ReaxFF/QEq have the ability and advantage to model electrochemical processes at a more realistic Coulomb interaction description and foster the processing of the details about the operation of electrochemical devices than the SRC.

Superconductivity, quantum capacitance, and electronic structure investigation of transition metals (X = Y, Zr, Nb, Mo) encapsulated silicon nanoclusters (Si59X): Intuition from quantum and molecular mechanics

Silicon nanoclusters (SiNCs) have unique structural and electronic properties that make them promising candidates for energy storage devices such as batteries, supercapacitors, and solar cells. This study theoretically investigated the superconducting and capacitance properties of transition metal (TM) doped silicon nanoclusters using density functional theory (DFT) calculations. The electronic and ionic conductivity, as well as the non-linear optic property, of TM-doped silicon nanoclusters herein, were analyzed to determine their potential as capacitor electrodes. The effects of temperature on electronic and ionic conductivity were also studied. The results suggest that TM doping enhances the superconducting and capacitance properties of silicon nanoclusters. The electronic conductivity was found to increase with increasing temperature, while the ionic conductivity showed a nonlinear relationship with temperature. Furthermore, it was observed that the doping of studied certain TM elements, such as Nb and Mo, leads to the formation of metallic states within the HOMO-LUMO energy range, indicating their potential for superconducting behaviour. The HOMO-LUMO analysis also reveals the electronic band structure and the bandgap of TM-doped silicon nanoclusters, showing that the dopants can tune the bandgap, resulting in improved superconductivity capacitance. The NBO analysis reveals the nature of bonding between the dopant atoms and the silicon atoms, indicating that charge transfer between the dopants and the silicon atoms plays a crucial role in enhancing the electronic properties Additionally, the stability of TM-doped silicon nanoclusters was analyzed, and it’s found that the doping with TM elements resulted in stable structures. The result strongly suggested that doping with Y, Zr, Nb, and Mo enhances the capacitance at different voltages and conductivity at elevated temperatures especially as the electronic configuration of the d-orbital of the dopant evolves. Overall, this study provides valuable insights into the potential of TM-doped silicon nanoclusters as efficient materials for superconducting and capacitive applications.

A neuron model with nonlinear membranes.

One-layer membrane separates the gradient field in and out of the cell, while some two-layer membranes filled with excitable media/material are important to regulate the energy flow when ions are propagated and diffused. The intracellular and extracellular media can be effectively separated by the membrane. It is important to clarify and describe the biophysical function and then the capacitive property can be reproduced in equivalent neural circuit. Here, we suggest the cell membrane has certain thickness and becomes flexible under external stimuli, therefore, it is considered as a kind of nonlinear media. To mimic the physical property of the two-layer cell membrane, a nonlinear resistor is used to connect two linear circuits, which is used to describe the electrical characteristic of two sides of the cell membrane, respectively. The combination of two linear circuits via a nonlinear resistor can describe the energy characteristic and firing mode in the flexible membrane of biophysical neurons. Circuit equations are defined and converted into equivalent nonlinear oscillator like a neuron. The voltage difference for the two capacitors can be consistent with the membrane potential for the neuron. The Hamilton energy function for this neuron can be mapped from the field energy in the electronic components, and it is also derived by using Helmholtz's theorem. The neuron can show similar spiking and bursting firing patterns, and uncertain diversity in membrane potentials is effective to support continuous firing patterns and mode transition under external stimulus. Furthermore, noisy disturbance is applied to induce coherence resonance. The results indicate that the lower coefficient variability and higher average energy level supports periodic firing in the neuron under coherence resonance. Therefore, this neuron model with nonlinear membranes (or two-layer form) is more suitable for identifying the biophysical property of biological neuron.

Physical approach of a neuron model with memristive membranes.

The membrane potential of a neuron is mainly controlled by the gradient distribution of electromagnetic field and concentration diversity between intracellular and extracellular ions. Without considering the thickness and material property, the electric characteristic of cell membrane is described by a capacitive variable and output voltage in an equivalent neural circuit. The flexible property of cell membrane enables controllability of endomembrane and outer membrane, and the capacitive properties and gradient field can be approached by double membranes connected by a memristor in an equivalent neural circuit. In this work, two capacitors connected by a memristor are used to mimic the physical property of two-layer membranes, and an inductive channel is added to the neural circuit. A biophysical neuron is obtained and the energy characteristic, dynamics, self-adaption is discussed, respectively. Coherence resonance and mode selection in adaptive way are detected under noisy excitation. The distribution of average energy function is effective to predict the appearance of coherence resonance. An adaptive law is proposed to control the capacitive parameters, and the controllability of cell membrane under external stimulus can be explained in theoretical way. The neuron with memristive membranes explains the self-adaptive mechanism of parameter changes and mode transition from energy viewpoint.

Design strategies of perovskite energy-storage dielectrics for next-generation capacitors

The next-generation capacitors have placed higher demands on energy-storage dielectrics, such as high temperature, high frequency and high voltage. Perovskite dielectrics possess various kinds of polar structures, such as ferroelectric domains, polar nano-regions (PNRs), and anti-polar structure as well, which exhibit various responses to external stimulations (temperature, electric field, mechanical loadings). Its design inspires development strategies to improve their energy-storage properties for capacitors involving chemical composition, fabrication process, computer simulation, and even measurement strategies for validation. In this article, we reviewed the recent design strategies and the perovskite dielectrics (covering linear, ferroelectric, relaxor ferroelectric, anti-ferroelectric, even some composite materials, such as glass-ceramics and polymer). This review spans from the atomic to millimeter-scale strategies of property optimization to provide accurate and comprehensive information for researchers in this field. Some novel proposals for overcoming the barriers between materials and properties are presented to accelerate the applications of the next-generation capacitors. Therefore, this review should help to identify the best approach for transferring the new perovskite dielectrics into next-generation capacitor applications.

Improving capacitance measurements of aqueous solutions with alpha and beta corrections in a parallel-plate capacitor system: Insights into dielectric properties

Radio-frequency (RF) heating relies on a parallel-plate capacitor heating applicator system, necessitates accurate capacitance measurements despite challenges posed by fringing fields. In this paper, we present protocols for improving capacitance measurements of aqueous solutions in a parallel-plate capacitor heating applicator system operating at a frequency of 27.12 MHz. Our method incorporates alpha and beta corrections to optimize the system, ensuring accurate capacitance measurements and enabling RF heating analysis of various samples. A parallel-plate capacitor was designed to be used for dielectric characterization in terms of capacitance and impedance of water and saline under various conditions at different working temperatures. The capacitance and dielectric properties of pure water and saline solutions with varying concentrations were measured at room temperature (25 °C) using a parallel-plate capacitor and RF probe, respectively. The effects of different concentrations of air, pure water, and saline solution on the capacitance of the parallel-plate capacitor heating applicator system were also studied. Alpha and beta values were estimated from simulations to improve the accuracy and precision of the measurements. Furthermore, our RF heating analysis revealed localized overheating at the edges and corners of dry soybeans, while the remaining areas of the sample exhibited improved heating uniformity. Simulations conducted with different heat transfer coefficients highlighted the significance of RF heating in different food products using a 6 kW, 27.12 MHz RF system. Our findings offer implications for designing optimum parallel-plate capacitor heating applicator systems, applicable to fields such as food processing, medical devices, water treatment, and environmental monitoring.

Heterostructured Ni2P/NiMo-layered double hydroxide nanoarrays with enriched redox active sites for supercapacitors

The electroactivity and cyclic stability of transition metal phosphides (TMPs) for supercapacitors are restricted by inadequate redox active sites and huge volume changes during the charging/discharging process. Herein, a three-dimensional (3D) porous Ni2P/NiMo-layered double hydroxide (NiMo-LDH) heterostructure with large specific surface and abundant pore channels is explored as a self-supporting supercapacitor electrode. The well-defined hierarchical pore structure can offer numerous electroactive sites and short ion/electron pathways. The generation of heterointerfaces between multi-dimensional Ni2P and two-dimensional (2D) NiMo-LDH nanosheets endows the hybrid composite with improved electrical conductivity and structural robustness. Consequently, the special nanoarchitecture design achieves a specific capacity of 198.6 mAh g−1 (2.28 mAh cm−2) at 1 A g−1 and an impressive rate performance of 78.3% at 20 A g−1. More importantly, the assembled Ni2P/NiMo-LDH//orange peel-derived porous carbon (OPC) asymmetric supercapacitor (ASC) device delivers a remarkable specific energy of 63.7 Wh kg−1 at a specific power of 1138.3 W kg−1 and long-term cycling stability (91.7% over 10,000 cycles). The research highlights that the hybridization of TMPs and other nanostructured battery-type materials may produce a synergistic effect and boost the capacitive properties.

Sinterability of sodium bismuth titanate-based electroceramics at low temperatures

The demand for robust multilayer ceramic capacitors with high-temperature and high-power capabilities is surging. Cost-effective production is a key challenge, often linked to precious metal electrodes like Pt, Pd, and Ag in multilayer ceramic capacitors (MLCCs). To address this, cost-efficient base metal electrodes such as Cu and Ni are sought. Promising lead-free options are Na0.5Bi0.5TiO3 (NBT)-based materials. However, their sintering temperatures exceed Cu's melting point (1085 °C), necessitating sintering aids for compatibility. We investigated several low-temperature sintering aids (Li2O, Na2O, Bi2O3, B2O3, ZnO, and V2O5) to lower the sintering temperature of Na0.5Bi0.5TiO3-BaTiO3-CaZrO3-BiAlO3 solid solutions. Results reveal NBT-based materials' sensitivity to acceptor dopant incorporation from sintering aids, impacting electrical properties. Yet, we successfully reduced the sintering temperature to 975 °C, suitable for Cu co-sintering, with minimal adverse effects on capacitor properties using well-tuned sintering aids.

Electrodeposition of Polyaniline on Tantalum: Redox Behavior, Morphology and Capacitive Properties

Polyaniline (PANI) is among the most widely studied conducting polymers due to its potential technological applications in various fields. Recently, PANI-based hybrid materials have played an important role in the development of energy storage and conversion systems. The aim of the present work is the investigation of the simultaneous electrochemical growth of PANI and Ta2O5 on the Ta substrate and the characterization of the morphology, redox behavior and pseudocapacitive properties of the resulting micro- or nanostructured composite thin films. A well-adherent conductive Ta2O5-PANI composite film was first formed using cyclic voltammetry on Ta that facilitates the on-top electrodeposition of single PANI via an autocatalytic mechanism. The electrochemical characterization of the Ta|Ta2O5-PANI|PANI electrodes reveals unique redox properties of PANI not shown previously upon using PANI electrodeposition on Ta. Scanning electron microscopy shows that the morphology of the electrodeposited films comprises nano- or microspheres that may develop into nano- or microrods when the polymerization proceeds. Preliminary evaluation of the capacitive properties of the Ta|Ta2O5-PANI|PANI electrode shows adequately high specific capacitance values as high as 1130 F g−1 (at 9.2 mA cm−2), depending on the electrochemical parameters, as well as adequate stability (~80% retention after 100 cycles), indicating their potential application as energy storage devices.

Electro-oxidation of persistent organic contaminants at graphene sponge electrodes using intermittent current

Borophene (Bph) and hexagonal boron nitride (hBN)-modified graphene sponge anode coupled to N-doped graphene sponge cathode were applied for electrochemical degradation of persistent organic contaminants using intermittent current. Three different ON-OFF pulse cycles were tested using low-conductivity supporting electrolyte in flow-through mode. Functionalization of the reduced graphene oxide (RGO) with Bph and hBN improved the ability of the double layer to store electrical charge, thus maintaining the generation of H2O2, O3, and ·OH even during the OFF cycles. Both anodes tested showed enhanced contaminant removal during shorter OFF periods (e.g. 52.5 s/52.s and 75 s/30 s ON/OFF), due to the improved retention of anode charge during the shorter OFF stages. Electrochemical removal of the target contaminants required 24 kWh m−3 in continuous current mode for both hBN-RGO and Bph-RGO anodes at 231 A/m−2, which was lowered to 11.7 and 13.5 kWh m−3 respectively, using ON-OFF pulse cycles. Electrochemical degradation pathways were elucidated in both systems using carbamazepine as a representative persistent contaminant. Flow-through reactors with both Bph- and hBN-RGO anodes removed ≥60 % of the target contaminants in a single pass using continuous current, whereas intermittent current led to somewhat decreased removal efficiencies (43–58 %) due to the scavenging effect of the wastewater matrix. Thus, halving the current ON time led to less than 20 % decrease in the removal efficiencies due to the capacitive properties of RGO. Given that switching to intermittent current decreased the energy consumption from 9.3 kWh m−3 to 4.4 kWh m−3 (Bph-RGO anode) and from 6.9 kWh m−3 to 3.6 kWh m−3 (hBN-RGO anode), higher removal of the target contaminants can be achieved by coupling sequential reactors in the intermittent current mode.

Experimental study of holographic metasurface for beam steering applications

In this article, a compact and high-gain, wide steering range and very low cross-polarization level holographic metasurface for beam steering is presented. The triangular modulated impedance surface is used for radiating the desired wave. The direction of the radiated beam is controlled through the varactor diode by changing the surface impedance of the device. The two prototypes of the designed device have been fabricated with two different varactor diodes. A higher gain of 11.7 dBi with a lower beam steering range of 25° and a radiation efficiency above 70% has been obtained from the device with a varactor diode SMV1405-079LF having lower parasitic resistance and larger capacitance properties. However, another fabricated device with higher parasitic resistance and lower capacitance property varactor diode SMV2201-40LF gives a lower gain of 9.1 dBi, a radiation efficiency below 55%, and a larger beam steering range of 61°. The experimental results are in good agreement with the simulation ones. The proposed device can be used for various applications like autonomous vehicles, toll plazas, and satellite communication.

Synthesis and Capacitive Properties of Mesoporous Tungsten Oxide Films Prepared by Ultrasonic Spray Deposition

Synthesis and Capacitive Properties of Mesoporous Tungsten Oxide Films Prepared by Ultrasonic Spray Deposition

Scalable fabrication of textile-based planar-structured supercapacitors with excellent capacitive performance

The researchers have been engaged in the development of textile-based high-performance flexible energy storage devices. The conventional fabrics are transformed into electrode composites by uniformly depositing polypyrrole (PPy) coating onto them using a simple interfacial solution polymerization method. The traditional textiles encompass cellulose fabrics such as cotton and ramie, protein fabrics like silk and wool, as well as chemical fiber fabric including polyester, polyamide, and acrylon. The PPy can be effectively coated onto the surface of cellulose fibers and penetrate into their interior, resulting in significantly higher loading capacity on cotton and ramie fabrics compared to other types of fibers. The two fabric electrodes (cotton@PPy and ramie@PPy) have better capacitive properties, especially the areal capacitance of ramie@PPy reaches 2836 mF cm−2. The PPy-coated fabric is precisely divided into standardized interdigital electrodes of consistent dimensions through the utilization of laser cutting techniques. The fabrication of a planar supercapacitor can be achieved through the straightforward assembly of two interdigital electrodes. The planar supercapacitor based on ramie@PPy shows a maximum energy density of 8.21 μWh cm−2 at power density of 0.20 mW cm−2. After undergoing 5000 cycles, the device demonstrates a remarkable ability to retain 90 % of its initial capacitance. The assembled supercapacitors exhibit exceptional flexibility and practicality, enabling power supply to electronic devices when connected in series. The fabric-based flexible supercapacitor can be easily mass-produced, making it a promising candidate for flexible energy storage devices.

Acupressure mat-like hierarchical structure of Ni3S2@Ti3C2Tx nanosheets as high rate capability and high power density electrodes for advanced supercapacitor

Layered material Ti3C2Tx has good pseudo capacitance properties, but its structure is unstable, and it was easily affected by water molecules in the air, which seriously limits its application in practical applications. The electrostatic self-assembly of nanoparticle Ni3S2 solid polyhedron provides more active sites for pseudo capacitive reaction, and the ion transport resistance is low, which provides a buffer space when the structure changes, and overcomes the structural instability of the carbon-based material (Ti3C2Tx) and the low theoretical specific capacity. Ti3C2Tx layered material was used as a stable conductive network substrate for charge transfer interconnection, which further improves the charge transfer rate between multi-layer structures, and successfully prepares Acupressure Mat-like Hierarchical Structure Ni3S2 @Ti3C2Tx composite material. It was capacity retention rate can reach 98% after 5000 cycles at a current density of 2 A/g. The assembled SSC unit has a huge potential window of 0–1.6 V, excellent magnification performance (93%), high power density (792.1 W/kg), and energy density (71.7 Wh/kg). The solid polyhedral Ni3S2 @layeredTi3C2Tx composite material has a good synergistic effect. It can synergistically reduce the expansion and collapse of materials, realize the steady improvement of electrochemical properties such as rate characteristics and energy density, and provide a potential application prospect for SSCs with high energy density.