Supercritical CO2 Synthesis of Freestanding Se1-xSx Foamy Cathodes for High-Performance Li-Se1-xSx Battery

Selenium-sulfur solid solutions (Se1-xSx) are considered to be a new class of promising cathodic materials for high-performance rechargeable lithium batteries owing to their superior electric conductivity than S and higher theoretical specific capacity than Se. In this work, high-performance Li-Se1-xSx batteries employed freestanding cathodes by encapsulating Se1-xSx in a N-doped carbon framework with three-dimensional (3D) interconnected porous structure (NC@SWCNTs) are proposed. Se1-xSx is uniformly dispersed in 3D porous carbon matrix with the assistance of supercritical CO2 (SC-CO2) technique. Impressively, NC@SWCNTs host not only provides spatial confinement for Se1-xSx and efficient physical/chemical adsorption of intermediates, but also offers a highly conductive framework to facilitate ion/electron transport. More importantly, the Se/S ratio of Se1-xSx plays an important role on the electrochemical performance of Li- Se1-xSx batteries. Benefiting from the rationally designed structure and chemical composition, NC@[email protected] cathode exhibits excellent cyclic stability (632 mA h g−1 at 200 cycle at 0.2 A g−1) and superior rate capability (415 mA h g−1 at 2.0 A g−1) in carbonate-based electrolyte. This novel NC@[email protected] cathode not only introduces a new strategy to design high-performance cathodes, but also provides a new approach to fabricate freestanding cathodes towards practical applications of high-energy-density rechargeable batteries.

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High-Performance Asymmetric Supercapacitors Based on the Ni1.5Co1.5S4@CNTs Nanocomposites

NANO ◽

10.1142/s1793292020501362 ◽

2020 ◽

Vol 15 (10) ◽

pp. 2050136

Author(s):

Xuan Zheng ◽

Xingxing He ◽

Jinlong Jiang ◽

Zhengfeng Jia ◽

Yu Li ◽

...

Keyword(s):

Energy Density ◽

Power Density ◽

High Performance ◽

Specific Capacity ◽

Negative Electrode ◽

High Energy ◽

Cycling Stability ◽

Power Delivery ◽

High Energy Density ◽

Practical Applications

In this paper, the Ni[Formula: see text]Co[Formula: see text]S4@CNTs nanocomposites containing different carbon nanotubes (CNT) content were prepared by a one-step hydrothermal method. More hydroxyl and carboxyl groups were introduced on the surface of CNTs by acidizing treatment to increase the dispersion of CNTs. The acid-treated CNTs can more fully compound with Ni[Formula: see text]Co[Formula: see text]S4 nanoparticles to form heterostructure. When the CNTs content is 10[Formula: see text]wt.%, the Ni[Formula: see text]Co[Formula: see text]S4@CNTs-10 nanocomposite exhibits the highest specific capacity of 210[Formula: see text]mAh[Formula: see text]g[Formula: see text] in KOH aqueous electrolytes at current density of 1[Formula: see text]A[Formula: see text]g[Formula: see text]. The superior performances of the Ni[Formula: see text]Co[Formula: see text]S4@CNTs-10 nanocomposite are attributed to the effective synergic effects of the high specific capacity of Ni[Formula: see text]Co[Formula: see text]S4 and the excellent conductivity of CNTs. An asymmetric supercapacitor (ASC) was assembled based on Ni[Formula: see text]Co[Formula: see text]S4@CNTs-10 positive electrode and activated carbon (AC) negative electrode, which delivers a high energy density of 61.2[Formula: see text]Wh[Formula: see text]kg[Formula: see text] at a power density of 800[Formula: see text]W[Formula: see text]kg[Formula: see text], and maintains 34.8[Formula: see text]Wh[Formula: see text]kg[Formula: see text] at a power density of 16079[Formula: see text]W[Formula: see text]kg[Formula: see text]. Also, the ASC device shows an excellent cycling stability with 91.49% capacity retention and above 94% Columbic efficiency after 10 000 cycles at 10[Formula: see text]A[Formula: see text]g[Formula: see text]. This aqueous asymmetric Ni[Formula: see text]Co[Formula: see text]S4@CNTs//AC supercapacitor is promising for practical applications due to its advantages such as high energy density, power delivery and cycling stability.

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Self-Supported NiSe/Ni Foam: An Efficient 3D Electrode for High-Performance Supercapacitors

NANO ◽

10.1142/s1793292018501369 ◽

2018 ◽

Vol 13 (11) ◽

pp. 1850136 ◽

Cited By ~ 1

Author(s):

Jingtong Zhang ◽

Fuzhen Zhao ◽

Kun Du ◽

Yan Zhou

Keyword(s):

High Performance ◽

Nickel Foam ◽

Specific Capacity ◽

Three Dimensional ◽

Electrochemical Capacitor ◽

High Energy ◽

Cycling Stability ◽

High Energy Density ◽

Acicular Structure ◽

Synthetic Reaction

Three-dimensional (3D) mixed phases NiSe nanoparticles growing on the nickel foam were synthesized via a simple one-step hydrothermal method. A series of experiments were carried out to control the morphology by adjusting the amount of selenium in the synthetic reaction. Meanwhile, the as-prepared novel column-acicular structure NiSe exist three advantages including ideal electrical conductivity, high specific capacity and high cycling stability. It delivered a high capacitance of 10.8[Formula: see text]F[Formula: see text]cm[Formula: see text] at a current density[Formula: see text] of 5[Formula: see text]mA[Formula: see text]cm[Formula: see text]. An electrochemical capacitor device operating at 1.6[Formula: see text]V was then constructed using NiSe/NF and activated carbon (AC) as positive and negative electrodes. Moreover, the device showed high energy density of 31[Formula: see text]W[Formula: see text]h[Formula: see text]kg[Formula: see text] at a power density of 0.81[Formula: see text]kW[Formula: see text]kg[Formula: see text], as well as good cycling stability (77% retention after 1500 cycles).

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High-Energy and High-Power Pseudocapacitor–Battery Hybrid Sodium-Ion Capacitor with Na+ Intercalation Pseudocapacitance Anode

Nano-Micro Letters ◽

10.1007/s40820-020-00567-2 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Qiulong Wei ◽

Qidong Li ◽

Yalong Jiang ◽

Yunlong Zhao ◽

Shuangshuang Tan ◽

...

Keyword(s):

Energy Density ◽

High Power ◽

Anode Materials ◽

High Performance ◽

Coulombic Efficiency ◽

Specific Capacity ◽

Rate Capability ◽

High Energy ◽

Sodium Ion ◽

High Energy Density

AbstractHigh-performance and low-cost sodium-ion capacitors (SICs) show tremendous potential applications in public transport and grid energy storage. However, conventional SICs are limited by the low specific capacity, poor rate capability, and low initial coulombic efficiency (ICE) of anode materials. Herein, we report layered iron vanadate (Fe5V15O39 (OH)9·9H2O) ultrathin nanosheets with a thickness of ~ 2.2 nm (FeVO UNSs) as a novel anode for rapid and reversible sodium-ion storage. According to in situ synchrotron X-ray diffractions and electrochemical analysis, the storage mechanism of FeVO UNSs anode is Na+ intercalation pseudocapacitance under a safe potential window. The FeVO UNSs anode delivers high ICE (93.86%), high reversible capacity (292 mAh g−1), excellent cycling stability, and remarkable rate capability. Furthermore, a pseudocapacitor–battery hybrid SIC (PBH-SIC) consisting of pseudocapacitor-type FeVO UNSs anode and battery-type Na3(VO)2(PO4)2F cathode is assembled with the elimination of presodiation treatments. The PBH-SIC involves faradaic reaction on both cathode and anode materials, delivering a high energy density of 126 Wh kg−1 at 91 W kg−1, a high power density of 7.6 kW kg−1 with an energy density of 43 Wh kg−1, and 9000 stable cycles. The tunable vanadate materials with high-performance Na+ intercalation pseudocapacitance provide a direction for developing next-generation high-energy capacitors.

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Enhanced Potassium-Ion Storage of the 3D Carbon Superstructure by Manipulating the Nitrogen-Doped Species and Morphology

Nano-Micro Letters ◽

10.1007/s40820-020-00525-y ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Yanhua Li ◽

Kui Xiao ◽

Cong Huang ◽

Jin Wang ◽

Ming Gao ◽

...

Keyword(s):

Energy Storage ◽

High Performance ◽

Density Functional ◽

Large Scale ◽

Specific Capacity ◽

Rate Capability ◽

High Energy ◽

Potassium Ion ◽

High Energy Density ◽

Superior Performance

Abstract Potassium-ion batteries (PIBs) are attractive for grid-scale energy storage due to the abundant potassium resource and high energy density. The key to achieving high-performance and large-scale energy storage technology lies in seeking eco-efficient synthetic processes to the design of suitable anode materials. Herein, a spherical sponge-like carbon superstructure (NCS) assembled by 2D nanosheets is rationally and efficiently designed for K+ storage. The optimized NCS electrode exhibits an outstanding rate capability, high reversible specific capacity (250 mAh g−1 at 200 mA g−1 after 300 cycles), and promising cycling performance (205 mAh g−1 at 1000 mA g−1 after 2000 cycles). The superior performance can be attributed to the unique robust spherical structure and 3D electrical transfer network together with nitrogen-rich nanosheets. Moreover, the regulation of the nitrogen doping types and morphology of NCS-5 is also discussed in detail based on the experiments results and density functional theory calculations. This strategy for manipulating the structure and properties of 3D materials is expected to meet the grand challenges for advanced carbon materials as high-performance PIB anodes in practical applications.

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Free-Standing and Heteroatoms-Doped Carbon Nanofiber Networks as a Binder-Free Flexible Electrode for High-Performance Supercapacitors

Nanomaterials ◽

10.3390/nano9091189 ◽

2019 ◽

Vol 9 (9) ◽

pp. 1189 ◽

Cited By ~ 4

Author(s):

Yan ◽

You ◽

Liu ◽

Wang ◽

Keyword(s):

High Performance ◽

Carbon Nanofiber ◽

Three Dimensional ◽

Rate Capability ◽

Mesoporous Structure ◽

High Energy ◽

High Energy Density ◽

Free Standing ◽

Electrode Cell ◽

Binder Free

Flexible and heteroatoms-doped (N, O and P) activated carbon nanofiber networks (ACFNs) have been successfully prepared with a mixture of polyamic acid (PAA) and poly(diaryloxyphosphazene) (PDPP) as a solution through electrospinning, followed by a heat post-treatment. The resultant heteroatoms-doped ACFNs can be used as binder-free electrodes for high-performance flexible supercapacitors (SCs) due to lightweight, three-dimensional open-pore structure and good mechanical strength. Despite its surface area being lower than 130.6 m2·g−1, the heteroatoms-doped ACFNs exhibited a high heteroatoms (N, O and P) content of 17.9%, resulting in a highly specific capacitance of 182 F·g−1 at a current density of 1 A·g−1 in 6 M KOH electrolyte in a two-electrode cell and an excellent rate capability of 74.7% of its initial capacitance from 1 A·g−1 to 10 A·g−1 under the mass loading of 1.5 mg·cm−2. The electrical double-layer (EDL) capacitance and pseudocapacitance can be easily decoupled in the heteroatoms-doped mesoporous ACFNs. SCs device based on heteroatoms-doped ACFNs exhibited a high energy density of 6.3 W·h·kg−1 with a power density of 250 W·kg−1, as well as excellent cycling stability with 88% capacitance retention after 10,000 charge–discharge cycles. The excellent electrochemical performance was attributed to the mesoporous structure of ACFNs and pseudocapacitive heteroatoms.

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Ultrathin nickel hydroxide on carbon coated 3D-porous copper structures for high performance supercapacitors

Physical Chemistry Chemical Physics ◽

10.1039/c7cp07473e ◽

2018 ◽

Vol 20 (2) ◽

pp. 719-727 ◽

Cited By ~ 18

Author(s):

Kyeong-Nam Kang ◽

Ik-Hee Kim ◽

Ananthakumar Ramadoss ◽

Sun-I Kim ◽

Jong-Chul Yoon ◽

...

Keyword(s):

Energy Density ◽

High Performance ◽

Three Dimensional ◽

Rate Capability ◽

High Energy ◽

High Energy Density ◽

Cycle Stability ◽

Porous Copper ◽

Carbon Coated ◽

Copper Structure

Ultrahigh rate capability, cycle stability, and high energy density supercapacitors supported by the three-dimensional (3D) carbon coated copper structure.

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Hierarchical coral-like MnCo2O4.5@Co-Ni LDH composites on Ni foam as promising electrodes for high-performance supercapacitor

Nanotechnology ◽

10.1088/1361-6528/ac3a3c ◽

2021 ◽

Author(s):

yajun JI ◽

Fei Chen ◽

Shufen Tan ◽

Fuyong Ren

Keyword(s):

Electrochemical Performance ◽

Metal Oxides ◽

High Performance ◽

High Capacity ◽

Rate Capability ◽

Negative Electrode ◽

High Energy ◽

Hybrid Nanostructures ◽

High Energy Density ◽

Ni Foam

Abstract Transition metal oxides are generally designed as hybrid nanostructures with high performance for supercapacitors by enjoying the advantages of various electroactive materials. In this paper, a convenient and efficient route had been proposed to prepare hierarchical coral-like MnCo2O4.5@Co-Ni LDH composites on Ni foam, in which MnCo2O4.5 nanowires were enlaced with ultrathin Co-Ni layered double hydroxides nanosheets to achieve high capacity electrodes for supercapacitors. Due to the synergistic effect of shell Co-Ni LDH and core MnCo2O4.5, the outstanding electrochemical performance in three-electrode configuration was triggered (high area capacitance of 5.08 F/cm2 at 3 mA/cm2 and excellent rate capability of maintaining 61.69 % at 20 mA/cm2), which is superior to those of MnCo2O4.5, Co-Ni LDH and other metal oxides based composites reported. Meanwhile, the as-prepared hierarchical MnCo2O4.5@Co-Ni LDH electrode delivered improved electrical conductivity than that of pristine MnCo2O4.5. Furthermore, the as-constructed asymmetric supercapacitor using MnCo2O4.5@Co-Ni LDH as positive and activated carbon as negative electrode presented a rather high energy density of 220 μWh/cm2 at 2400 μW/cm2 and extraordinary cycling durability with the 100.0 % capacitance retention over 8000 cycles at 20 mA/cm2, demonstrating the best electrochemical performance compared to other asymmetric supercapacitors using metal oxides based composites as positive electrode material. It can be expected that the obtained MnCo2O4.5@Co-Ni LDH could be used as the high performance and cost-effective electrode in supercapacitors.

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Bio-inspired low-tortuosity carbon host for high-performance lithium-metal anode

National Science Review ◽

10.1093/nsr/nwy148 ◽

2018 ◽

Vol 6 (2) ◽

pp. 247-256 ◽

Cited By ~ 14

Author(s):

Yi-Chen Yin ◽

Zhi-Long Yu ◽

Zhi-Yuan Ma ◽

Tian-Wen Zhang ◽

Yu-Yang Lu ◽

...

Keyword(s):

Volume Change ◽

High Performance ◽

Rate Capability ◽

High Energy ◽

High Energy Density ◽

Lithium Metal ◽

Metal Anode ◽

Lithium Metal Anode ◽

Nucleation Sites ◽

Micro Channels

Abstract Lithium metal is one of the most promising anode materials for high-energy-density Li batteries. However, low stability caused by dendrite growth and volume change during cycling hinders its practical application. Herein, we report an ingenious design of bio-inspired low-tortuosity carbon with tunable vertical micro-channels to be used as a host to incorporate nanosized Sn/Ni alloy nucleation sites, which can guide Li metal's plating/stripping and meanwhile accommodate the volume change. The pore sizes of the vertical channels of the carbon host can be regulated to investigate the structure–performance correlation. After compositing Li, the bio-inspired carbon host with the smallest pore size (∼14 μm) of vertical channels exhibits the lowest overpotential (∼18 mV at 1 mA cm−2), most stable tripping/plating voltage profiles, and best cycling stability (up to 500 cycles) in symmetrical cells. Notably, the carbon/Li composite anode is more rewarding than Li foil when coupled with LiFePO4 in full cells, exhibiting a much lower polarization effect, better rate capability and higher capacity retention (90.6% after 120 cycles). This novel bio-inspired design of a low-tortuosity carbon host with nanoalloy coatings may open a new avenue for fabricating advanced Li-metal batteries with high performance.

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Synthesis of Si/Fe2O3-Anchored rGO Frameworks as High-Performance Anodes for Li-Ion Batteries

International Journal of Molecular Sciences ◽

10.3390/ijms222011041 ◽

2021 ◽

Vol 22 (20) ◽

pp. 11041

Author(s):

Yajing Yan ◽

Yanxu Chen ◽

Yongyan Li ◽

Xiaoyu Wu ◽

Chao Jin ◽

...

Keyword(s):

High Performance ◽

Melt Spinning ◽

Three Dimensional ◽

High Capacity ◽

Reversible Capacity ◽

High Energy ◽

High Specific Surface Area ◽

High Energy Density ◽

Active Components ◽

Li Ion

By virtue of the high theoretical capacity of Si, Si-related materials have been developed as promising anode candidates for high-energy-density batteries. During repeated charge/discharge cycling, however, severe volumetric variation induces the pulverization and peeling of active components, causing rapid capacity decay and even development stagnation in high-capacity batteries. In this study, the Si/Fe2O3-anchored rGO framework was prepared by introducing ball milling into a melt spinning and dealloying process. As the Li-ion battery (LIB) anode, it presents a high reversible capacity of 1744.5 mAh g−1 at 200 mA g−1 after 200 cycles and 889.4 mAh g−1 at 5 A g−1 after 500 cycles. The outstanding electrochemical performance is due to the three-dimensional cross-linked porous framework with a high specific surface area, which is helpful to the transmission of ions and electrons. Moreover, with the cooperation of rGO, the volume expansion of Si is effectively alleviated, thus improving cycling stability. The work provides insights for the design and preparation of Si-based materials for high-performance LIB applications.

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Nitrogen-rich covalent organic frameworks with multiple carbonyls for high-performance sodium batteries

Nature Communications ◽

10.1038/s41467-019-13739-5 ◽

2020 ◽

Vol 11 (1) ◽

Cited By ~ 32

Author(s):

Ruijuan Shi ◽

Luojia Liu ◽

Yong Lu ◽

Chenchen Wang ◽

Yixin Li ◽

...

Keyword(s):

High Performance ◽

Density Functional ◽

Specific Capacity ◽

Density Functional Theory Calculations ◽

Rechargeable Batteries ◽

High Rate ◽

Ex Situ ◽

Covalent Organic Frameworks ◽

Rate Performance ◽

Practical Applications

AbstractCovalent organic frameworks with designable periodic skeletons and ordered nanopores have attracted increasing attention as promising cathode materials for rechargeable batteries. However, the reported cathodes are plagued by limited capacity and unsatisfying rate performance. Here we report a honeycomb-like nitrogen-rich covalent organic framework with multiple carbonyls. The sodium storage ability of pyrazines and carbonyls and the up-to twelve sodium-ion redox chemistry mechanism for each repetitive unit have been demonstrated by in/ex-situ Fourier transform infrared spectra and density functional theory calculations. The insoluble electrode exhibits a remarkably high specific capacity of 452.0 mAh g−1, excellent cycling stability (~96% capacity retention after 1000 cycles) and high rate performance (134.3 mAh g−1 at 10.0 A g−1). Furthermore, a pouch-type battery is assembled, displaying the gravimetric and volumetric energy density of 101.1 Wh kg−1cell and 78.5 Wh L−1cell, respectively, indicating potentially practical applications of conjugated polymers in rechargeable batteries.

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