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1.
《Ceramics International》2022,48(7):9781-9787
A cohesive architecture of 1T-MoS2 covered by PPy composite (1T-MoS2@PPy) is successfully fabricated by a simple hydrothermal reaction followed by an in-situ polymerization route. The composite material consists of 1T-MoS2 hollow microsphere and conductive PPy coating layer. The cohesive architecture enables the composite to show rapid shuttle of electrons/lithium ions and good ductility to buffer the volume changes during charging and discharging process when it is used as anode material. As expected, 1T-MoS2@PPy composite exhibits a favorable discharge capacity up to 970.3 and 407.1 mAh g?1 at 0.2 and 3 A g?1, respectively. In addition, the composite also achieves impressive cycling performance of 717.1 mAh g?1 at 1 A g-1 after 500 cycles. This study provides a meaningful guidance in rational design of anode materials with cohesive architecture as well as high electrochemical performance.  相似文献   

2.
《Ceramics International》2022,48(14):20324-20331
As one of the typical MXenes materials, 2D Ti3C2Tx has attracted extensive attention in the field of energy storage. However, due to the restacking problem of Ti3C2Tx nanosheets, the electrochemical performance of Ti3C2Tx is unsatisfactory. In this paper, a scheme is proposed to obtain 3D aerogel with 1D channels by directional freeze drying of Ti3C2Tx. With the help of the unidirectional channels, the 3D Ti3C2Tx/Sodium alginate (SA) aerogel can effectively solve the stacking problem of Ti3C2Tx nanosheets, and it also accelerates the diffusion of ions. The Ti3C2Tx/SA-5 electrode can still reach the mass capacitance of 284.5 F g?1 and the areal capacitance of 4030.4 mF cm?2 at 2 mV s?1 when the loading is 14.2 mg cm?2 in 1 M H2SO4 electrolyte. In addition, the electrode showed good cycling performance without capacitor degradation after 20,000 cycles at 50 mV s?1. These results suggest that by using the strategy of building special 3D structure of 2D MXene with 1D unidirectional channels, high performance supercapacitor electrodes with high mass loading can be realized.  相似文献   

3.
Thickness and specific surface area of the film electrode are critical parameters for supercapacitors. The relationship between the thickness and the specific surface area of the film directly affects the capacitance and electrochemical stability performance of super supercapacitors, which virtually affects the contact chance of ion in the electrolyte on the surface of electrode and the ion transport path of electrode. In this paper, the CrN thin films with a thickness of 200–3500 nm are prepared using direct current magnetron sputtering. Atomic force microscopy (AFM) technique is introduced to investigate the relationship between thickness and the specific surface area of the CrN films. The electrochemical performances of CrN electrode with the nanoporousper structure is analyzed in different electrolytes H2SO4, Na2SO4 and NaCl aquous solutions. The specific surface area of the film increases linearly with the film thickness increases. The areal capacitance is also linearly related to the specific surface area. The spurtted CrN film with a thickness of 3370 nm has a specific surface of up to 43.59 cm2 per cm2 footprint area. Its areal and volume capacitances reache to 53.92 mF cm?2 and 650 F cm?3 at 5 mV s?1, respectively. In addition, the areal capacitance of CrN film electrode with 655 nm possesses reaches to 40.53 mF cm?2 for 0.5 M H2SO4 solution, 32.69 mF cm?2 for 0.5 M Na2SO4 solution and 9.17 mF cm?2 for NaCl solution at a scan rate of 5 mV s?1. Furthermore, the CrN film electrode exhibits excellent capacitance retention of 95.3%, 93.8% and 89.9% in H2SO4, Na2SO4 and NaCl electrolytes, respectively, after 2000 cycles. Therefore, the sputtered CrN thin film is an potential electrode material for electrochemical supercapacitors.  相似文献   

4.
In this work, we employed a simple and cost-effective chemical route to obtain a highly stable and efficient quaternary mesoporous 3D nanoflower-like NiCuCo2S4 nanocomposite for supercapacitor applications. The NiCuCo2S4 composite exhibited a mixture of NiCo2S4 and CuCo2S4 phases, confirming the formation a quaternary NiCuCo2S4 thin film. A surface morphological analysis revealed the unique nanoflower-like nanostructure of the annealed composite. The electrochemical analysis of the NiCuCo2S4 electrode demonstrated a high specific capacity (Cs) of 414 mAh g?1 at a lower scan rate of 10 mV s?1 and a superior cycling stability up to 3000 cycles. A solid-state hybrid supercapacitor (SHS) was also constructed by the NiCuCo2S4 and AC powder as positive and negative electrodes, respectively. The NiCuCo2S4//AC hybrid cell produced a high Cs, energy density, and power density of 159 F g?1, 35.19 Wh kg?1, and 0.66 kW kg?1, respectively at a current density of 10 mA with good cycling stability. The results demonstrated that the fabrication process is effective for the development of a novel quaternary transition metal sulfide (TMS) electrode.  相似文献   

5.
《Ceramics International》2022,48(17):25020-25033
Herein, we have developed a novel hybrid material based on NiCo2S4 (NCS), halloysite nanotubes (HNTs), and carbon as promising electrodes for supercapacitors (SCs). Firstly, mesoporous NCS nanoflakes were prepared by co-precipitation method followed by physically mixing with HNTs and carbon, and screen printed on nickel foam. After ultrasonication, a uniform distribution of the Carbon/HNTs complex was observed, which was confirmed by surface morphological analysis. When used as electrode material, the NCS/HNTs/C hybrid displayed a maximum specific capacity of 544 mAh g?1 at a scan rate of 5 mV s?1. Later, a solid-state hybrid SCs was fabricated using activated carbon (AC) as the negative and NCS/HNTs/C as the positive electrode (NCS/HNTs/C//AC). The device delivers a high energy density of 42.66 Wh kg?1 at a power density of 8.36 kW kg?1. In addition, the device demonstrates long-term cycling stability. Furthermore, the optimized NCS, NCS/HNTs, and NCS/HNTs/C nanocomposites also presented superior hydrogen evolution reaction (HER) performance of 201, 169, and 116 mV in the acidic bath at a current density of 10 mA cm?2, respectively. Thus, the synthesis of NCS/HNTs/C nanocomposite as positive electrodes for hybrid SCs opens new opportunities for the development of next-generation high energy density SCs.  相似文献   

6.

CoZn layered double hydroxide (LDH) or Co(OH)2 pseudocapacitive material has been prepared on the current collector of carbon fiber paper (CFP) using an eco-friendly one-step electrodeposition. Benefiting from its unique structural feature, the binder-free CoZn LDH/CFP electrode material realizes high specific capacitance of 1156 Fg?1 at a current density of 1 Ag?1 and excellent rate capability of 80% retention with 16 fold current density increment, which is much better than that of Co(OH)2 (617 Fg?1, 65%). Notably, the CoZn LDH/CFP can retain an outstanding electrochemical stability with a capacitance degradation of only 6% after 6000 charge–discharge cycles at 32 Ag?1. Moreover, an asymmetric supercapacitor (ASC) using CoZn LDH/CFP as a positive electrode and AC/CFP as a negative electrode has been assembled. The ASC exhibits a superior energy density of 30.0 Whkg?1 at a power density of 800 Wkg?1 with a specific capacitance up to 84.4 Fg?1 and a potential window wide to 1.6 V. These encouraging results indicate that CoZn LDH/CFP composite material has a great potential for next-generation energy conversion/storage devices.

  相似文献   

7.
《Ceramics International》2021,47(19):26758-26767
Titanium nitride (TiN) is widely used in electrode materials in fast charging/discharging supercapacitors (SCs) due to its outstanding conductivity. However, the low capacitance of the TiN electrode limits its further application in the SCs. Therefore, the reasonable design of the TiN electrode with high electrochemical and mechanical properties is still a challenge. In this paper, the silicon nanowires/titanium nitride electrode (Si NWs/TiN) is prepared by depositing TiN onto the etched Si nanowires by direct current magnetron sputtering. The Si NWs are prepared by etching silicon in 4.8 M HF/0.02 M AgNO3 aqueous solution for different times (5 min, 15 min, 30 min, 60 min). The mechanism of the effect of etched silicon substrate morphology on the electrochemical performance of Si NWs/TiN electrode was studied. As the etching time increases, the differences of the TiN surface structure, lattice defects and surface chemical composition will change the capacitance performance and charge storage mechanism of the Si NWs/TiN electrode. The prepared Si30 NWs/TiN electrode exhibits an outstanding specific capacitance as high as 113.55 F g−1 at a scan rate of 5 mV s−1 with 0.5 M H2SO4 solution as electrolyte. The specific capacitance of the Si30 NWs/TiN electrode is as high as 7.5 times that of the electrode without etching at 100 mV s−1. The Si30 NWs/TiN electrode has an excellent cyclic stability performance, which the electrode has a decay rate of 12.4% after 2000 cycles. This indicates that the electrode has reliable stability. The electrode of the supercapacitor prepared by this method can open up a new way to expand the specific surface area of other transition metal nitride.  相似文献   

8.
《Ceramics International》2022,48(12):16516-16521
Manganese oxides have been regarded as one of the most promising electrode materials for energy storage systems. Especially, they can be used as battery-type electrodes in hybrid supercapacitors to achieve high energy density and power density at the same time. In such an application, the redox reaction on the battery-type electrodes needs to speed up to match the fast charging-discharging process of the counter capacitive electrodes. Herein, we intercalated K+ ions into MnO2 to enlarge the interlayer space as channels for ion diffusion, and coated the particles with carbon layer to achieve fast charging/discharging ability. The obtained KxMnO@C particles delivered a high specific capacitance of 1039 F g?1 in 5 M LiTFSI aqueous electrolyte. Coupled with activated carbon anode, the hybrid supercapacitor showed outstanding energy and power density.  相似文献   

9.
The present study emulates a one-pot facile synthesis of selenium-enriched CoSe nanotube using a chemical bath deposition (CBD) procedure. Schematic incorporation of 3D Ni foam current collectors as substrates for the growth of CoSe–Se nanotubes helped us achieve a binder-less thin film coating. The controlled synthesis of CoSe–Se nanotube was carried out by optimizing the temperature and time of the deposition. CoSe–Se nanotubes were grown on a porous Ni foam substrate using lithium chloride as a shape directing agent. The study found that the one dimensional structure of the nanotubes with porous nature results in an uninterrupted network of electroactive sites. Due to the superior conductivity, the as-fabricated material exhibited excellent rate capability and a higher degree of electrolyte ion diffusion across the CoSe–Se crystal structure. The CoSe–Se@Ni foam electrodes exhibited a specific capacitance of 1750.81 F g?1 at 1 A g?1. The electrode exhibited excellent cycling stability and showed a capacitance retention of 95% after 4000 charge-discharge cycles. Finally, an asymmetric supercapacitor (ASC) device was fabricated with the as-synthesized CoSe–Se@Ni foam electrode as the cathode, activated carbon@Ni foam electrode as the anode, and a thin filter paper separator soaked in 1 M aqueous KOH electrolyte solution. The ASC device showed a specific capacitance value of 106.73 F g?1 at 0.5 A g?1, and achieved an energy density of 37.94 Wh kg?1 at a power density of 475.30 W kg?1. The ASC device was utilized in an extended potential window of 1.6 V. The fabricated device displayed exceptional cycling stability with a capacitance retention of 93% after 5000 charge-discharge cycles.  相似文献   

10.
The incorporation of nanosized pseudocapacitive materials and structure design are general strategies to enhance the electrochemical performance of MXene-based materials. Herein, the decoration of manganese dioxide (MnO2) nanosheets on MXene (Ti3C2Tx) surfaces was prepared by a facile liquid phase coprecipitation method. Ti3C2Tx is initially modified by polydopamine (PDA) coating to ensure the homogeneous distribution of MnO2 nanosheets and tight and close connections between MnO2 and the Ti3C2Tx backbone. Due to the obtained three-dimensional (3D) nanostructure, facilitating electron transport within the electrode and promoting electrolyte ion accessibility, the δ-MnO2@Ti3C2Tx-0.06 electrode yields superior electrochemical performances, such as a rather large areal capacity of 1233.1 mF cm?2 and high specific capacitance of 337.6 F g?1 at 2 mV s?1, as well as high cyclic stability for 10000 cycles. Furthermore, δ-MnO2@Ti3C2Tx-0.06 composites are employed as positive electrodes, and activated carbon (AC) materials act as negative electrodes with an aqueous electrolyte of 1 M Na2SO4 to assemble asymmetric supercapacitors. The prototype device is reversible at cell voltages from 0 to 1.8 V, and manifests a maximum energy density of 31.4 Wh kg?1 and a maximum power density of 2700 W kg?1. These encouraging results show enormous possibilities for energy storage applications.  相似文献   

11.
A novel eutectoid structure, WxC-embedded WS2 nanosheets hybrids composite, was developed by hydrothermal reaction followed by a carbonization process. The fabricated WS2–WxC hybrid nanosheets electrode was used for lithium-ion batteries as an anode material, and demonstrated the specific capacity of 272 mA h·g?1 at 0.01 A g?1 with enhanced rate competence and cycling behavior when compared with individual WS2 and W2C electrode. While the large interlayer spacing in WS2 facilitates rapid Li+ transport, the extremely high electronic conductivity of WxC provides a highly conductive electron transfer pathway, which facilitates fast and reversible (de)lithiation reactions during charging and discharging. Further, these outcomes point the way for developing future eutectoid hybrid systems for advanced energy-storage applications.  相似文献   

12.
《Ceramics International》2022,48(21):31598-31605
A strategy to enhance the electrochemical performance of a single-crystal LiNixMnyCozO2 (NCM) electrode is proposed herein based on a preferred orientation of a Li diffusion pathway along the working direction under an ordinary 0.4-T magnetic field. Hexagonal NCM622 single crystals can be aligned along their crystallographic c-axis parallel to the applied magnetic field because the crystal has an easy magnetization axis along the c-axis. The horizontal magnetic field–oriented NCM622 cathode (HMFC) shows inhibited polarization and increased lithium-ion conductivity. The suppressed polarization promotes cyclability, increasing the specific capacity from 157.93 to 168.75 mAhg?1 after the 100th cycle at 0.5 C. Furthermore, the increased diffusion coefficient (from 3.06 × 10?10 cm2s?1 to 7.12 × 10?10 cm2s?1) causes substantial improvement in the rate performance, achieving a high specific capacity of 130.77 mAhg?1 at 10 C, while the electrode without magnetic treatment achieves a specific capacity of only 115.88 mAhg?1. Owing to such a superior electrochemical performance, the HMFC electrodes show high potential for lithium-ion batteries in the EV industry. Decreasing the magnetic field from 6 to 0.4 T for cathode alignment facilitates the applicability of the proposed strategy to production lines of battery plants using commercially available permanent magnets because a magnetic field of 0.4 T is easily achievable.  相似文献   

13.
《Ceramics International》2017,43(2):2155-2164
The development of wearable electronics has created a surge of interest in designing flexible energy storage device with high energy density and long lifespan. In this work, we have successfully fabricated a flexible asymmetric supercapacitor (ASC) based on the NiCo2S4@NiCo2O4 nanocolumn arrays (NCAs). The nickel cobalt sulfide/oxide core-shell nanostructures were rationally synthesized through a facile stepwise approach. The NiCo2S4@NiCo2O4 NCAs based electrode delivered a high specific capacitance of 2258.9 F g−1 at a current density of 0.5 A g−1. The as-assembled flexible ASC device exhibited a high energy density of 44.06 Wh kg−1, a high power density of 6.4 kW kg−1, and excellent cycling stability by retaining 92.5% after 6000 cycles. Excitingly, the electrochemical property of the ASC device could be maintained under severe bending, indicating superior flexibility and mechanical stability. The NiCo2S4@NiCo2O4 core-shell NCAs possess enormous potential for future wearable electronic applications.  相似文献   

14.
Novel nanostructured Fe2O3 with a network of 3D mesoporous nanosheets was synthesized by depositing on carbon fabric (Fe2O3@CF) for use as an anode using a potentially low-cost electrodeposition technique. The electrode with freestanding binder-free Fe2O3@CF of high surface area displayed an exceptional specific capacitance of 394.2?F?g?1. Moreover, a flexible solid-state asymmetric supercapacitor (ASC) was fabricated with a negative electrode based on Fe2O3@CF and a positive electrode based on MnO2@CF in the presence of PVA-LiCl as gel electrolyte. The above ASC exhibited a high operating potential up to 1.8?V, a favorable specific capacitance of 93.5?F?g?1 (2.92?F?cm?3), long-term stability (91.3% retention of initial value over 5000 cycles), and remarkable mechanical stability and flexibility, suggesting its potential application for wearable electronics.  相似文献   

15.
A composite electrode based on polyaniline (PANI) and hydrous RuO2 is prepared by electrochemical deposition of PANI onto hydrous RuO2 (PANI/RuO2) and its supercapacitive properties are investigated using cyclic voltammetry. The specific capacitances of PANI/RuO2 and hydrous RuO2 electrodes are determined to be 708 and 517 F g−1 at 5 mV s−1, respectively. Simple electrodeposition of PANI on the hydrous RuO2 can achieve comparatively greater capacitance values.  相似文献   

16.
《Ceramics International》2023,49(2):2380-2387
Copper-based oxides are attractive anode materials for lithium-ion batteries (LIBs) due to their abundant resources, low cost, non-toxic and high capacity. However, copper-based oxides will produce a huge volume change during lithiation/delithiation, and the structural strain caused by periodic volume changes may cause the exfoliation of active materials. Herein, a flower-like binder-free three-dimensional (3D) CuO/Cu2O-CTAB was prepared by introducing CTAB, which homogeneously grew in situ on a copper mesh framework. The binder-free 3D sample guarantees direct contact between the active material and the copper mesh, maintaining the structure stability. The flower-like CuO/Cu2O-CTAB with a small size reveals larger active interfaces and provides more active sites. The introduction of CTAB enlarges the interlayer spacing of CuO/Cu2O, increases the active sites for lithium storage, and adapts to the volume change of the material during lithiation/delithiation. In addition, the expanded interlayer structure helps decrease the ion diffusion energy barrier for accelerating electrochemical reaction kinetics. Therefore, CuO/Cu2O-CTAB exhibits better lithium storage performance (2.9 mAh cm?2 at 0.5 mA cm?2) than bare CuO/Cu2O (1.8 mAh cm?2 at 0.5 mA cm?2).  相似文献   

17.
A novel gadolinium selective coated graphite electrode based on 2,6-bis-[1-{N-cyanopropyl,N-(2-methylpridyl)}aminoethyl]pyridine [P] is described. The best performance was exhibited by the electrode having membrane composition P:NaTPB:PVC:NPOE as 8:4:30:58 (%, w/w). The electrode demonstrates excellent potentiometric characteristics towards gadolinium ion over several interfering ions. The electrode exhibited a Nernstian response to Gd3+ ion over a wide concentration range 2.8 × 10−7 to 5.0 × 10−2 M with a detection limit (6.3 ± 0.1) × 10−8 M and slope 19.6 ± 0.1 mV decade−1 of aGd3+. Furthermore, it showed a fast response time (12 s) and can be used for 2.5 months without significant divergence in its characteristics. Noticeably, the electrode can tolerate the concentration of different surfactants up to 1.0 × 10−4 M and can be used successfully in 30% (v/v) ethanol media and 10% (v/v) methanol and acetonitrile water mixture. The useful pH range of this sensor is 2.0 to 8.0. It is sufficiently selective and can be used for the determination of Gd3+ ions in waste water and rock samples. It also serves as a good indicator in the potentiometric titration of GdCl3 with EDTA.  相似文献   

18.
A silicon based composite (Si@SiO2/CNTs) with outstanding electrochemistry performance has been easily synthesized using a spray drying method; The composite microsphere is mainly made up of carbon nanotubes and the prepared nano silicon particles. With the help of a silane coupling agent, carbon nanotubes tightly intertwined with nano silicon particles and formed microspheres together. On the surface of the prepared nano silicon particles, a layer of oxide film plays a role as a barrier to reduce the rupture of the particles during the lithium intercalation/extraction process. In addition, the added twisted carbon nanotubes can help to maintain the conductive network, thus stabilizing the electrode working environment during the lithium intercalation/extraction process. As a superior anode material, an initial specific discharge capacity of approximately 2846.9 mAh g?1 with a coulombic efficiency of 86 % and a reversible specific capacity of 2035.9 mAh g?1 after 100 cycles at a constant density of 500 mA g?1 are obtained.  相似文献   

19.
In the present work, submicrometer CoMoO4 is successfully prepared by a facile polymer-pyrolysis method. The phase, structure, composition and morphology of the obtained sample are characterized by several techniques. The proper reaction temperature is 600 °C. As an anode material of lithium half-battery, the sample prepared at 600 °C exhibits a stable reversible capacity of 667.6 mAh g?1 at a current density of 0.2 A g?1. A 96.7% capacity retention is observed between 10 and 100 cycles, where lithium storage reaction is dominated by ionic diffusion, and the diffusion coefficient of lithium ion is about 0.12 × 10?15 cm2 s?1. As electrode of supercapacitors, a high specific capacitance of around 304.6 F g?1 is achieved at a current density of 0.5 A g?1 after 1000 cycles. Therefore, the polymer-pyrolysis method shows great promise in preparing the CoMoO4.  相似文献   

20.
《Ceramics International》2020,46(13):21482-21488
Two-dimensional transition metal carbide (MXene) is a promising electrode material for supercapacitors because of its excellent electrochemical properties. Here, we report a controllable and facile strategy to prepare a freestanding and flexible N-doped Ti3C2Tx (N–Ti3C2Tx) film electrode with a hydrothermal method using hydrazine hydrate (N2H4∙H2O) as a nitrogen source. At a scan rate of 2 mV s−1, the N–Ti3C2Tx film electrode exhibits a high specific capacitance of 340 F g−1 and no capacitance degradation after 10,000 cycles in 1 M H2SO4 electrolyte. These results show that the N–Ti3C2Tx film could be used as an outstanding electrode material for high-performance supercapacitors. The operation of hydrazine treatment provides a more practical and convenient experimental method for N-doping.  相似文献   

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