Journal of Energy Storage
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2024
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IF 8.9
Bin Hu,Wenxuan Hu,Xinyuan Qian,Min Zuo,Ziliang Wu,Yihu Song,Qiang Zheng,Guorong Shan,Miao Du
Layered double hydroxides (LDHs) have garnered significant attention as electrode materials for their ultra-high theoretical capacitance. However, LDHs are prone to phase transition and volume changes during charge/discharge process, which adversely affect their cyclic stability and applications. In this paper, a small amount of non-electrochemically active element, scandium (Sc), was firstly introduced into NiCo-LDHs by a facile and fast one-step potentiostatic electrodeposition with NH 4 Br as a modulator, effectively mitigating the influence of the Jahn-Teller effect. By doping slight Sc into NiCo-LDHs, the resulting electrode exhibited excellent electrochemical performance , with a specific capacitance of 1994 F g −1 (at 1 A g −1 ), and ultralong lifespan, retaining 82.7 % of its initial capacitance after 30,000 charge-discharge cycles. This work presents a promising strategy for the rapid preparation of LDHs-based supercapacitor electrodes that deliver both high specific capacitance and outstanding cycling performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Li Liu,Jing Mo,Jie Xu,Yangxi Liu,Ruoxi Yang,Xiaohui Yang,Xinguo Ma,Wensheng Fu
Heterojunction has the characteristics of adjusting catalyst structure, improving oxygen evolution kinetics and breaking the elevated reaction barrier of oxygen evolution process. In this paper, a heterostructure catalyst of NiCo-LDHs nanosheets encapsulated CuS hollow nano-octahedrals has been reported, which has better stability and higher mass transfer efficiency compared with two-dimensional nanosheets. Density functional theory (DFT) calculations indicate that the heterostructure strengthens the orbital hybridization of metal 3 d and O 2 p , at the same time, the heterointerface coupling induces the directional movement of electrons from NiCo-LDHs to CuS, which together provide abundant high-valence Ni and Co active sites, promote the conversion of *OH to *O species, thus reducing the energy required for the reaction. Hence, CuS@NiCo-LDHs exhibits excellent OER performance and good stability in 1 M KOH. When the current density is 10 mA/cm 2 , the overpotential and Tafel slope of this catalyst is only 253 mV and 56 mV/dec, respectively. This study furnishes the construction of heterogeneous structures and the catalyst exploitation with serviceable insights.
研究领域:
催化
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材料科学
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电化学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2020
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IF 4.65
Biying Liu,Man Zhang,Yuchen Wang,Zuo Chen,Kai Yan
Layered double hydroxides (LDHs) containing transition metals with unsaturated d-bands are ideal candidates for oxygen evolution reaction (OER). However, the bulk layers and congested interlayers block the active sites and avoid the electrolyte access to the internal space. In this work, we report a simple coprecipitation coupled with the hydrothermal method for the direct growth of bimetallic NiCo-LDHs (5.01 nm), NiMn-LDHs (3.45 nm) and trimetallic NiCoMn-LDHs nanosheets (1.26 nm) on Ni foam and these fabricated electrodes exhibit the superior performance for OER. Notably, the NiCoMn-LDHs nanosheets exhibit the lowest overpotential of 290 mV at 20 mA cm −2 and the smallest Tafel slope of 87 mV dec −1 , reducing by 20–40 mV and 31–39 mV dec −1 in comparison with those of bimetallic NiCo-LDHs (310 mV, 118 mV dec −1 ) and NiMn-LDHs (330 mV, 126 mV dec −1 ). This excellent performance is attributed to the 2D structure of the nanosheets and an abundance of exposed active sites, especially oxygen vacancies . Additionally, NiCoMn-LDHs nanosheets exhibit the smallest charge transfer resistance (R ct ) of 6.3 Ω and the largest electrochemical double layer capacitance (C dl ) of 5.52 mF cm −2 than those of the bimetallic NiCo-LDHs (11.0 Ω, 4.85 mF cm −2 ) and NiMn-LDHs (30.6 Ω, 3.00 mF cm −2 ). Furthermore, NiCoMn-LDHs nanosheets maintain good durability over 10 h and cyclic stability without distinct change. This work offers a facile strategy to design various types of bimetallic and trimetallic LDHs boosting for OER process.
研究领域:
电化学
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材料科学
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能源材料
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
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2023
·
IF 9.4
Guiquan Liu,Guorong Wang,Zhiliang Jin
Nickel-based hydrotalcite has been widely used in supercapacitor electrodes due to its multivalence. Unfortunately, the poor stability and low conductivity for charge transfer impede further development in the field of energy storage. Herein, the graphdiyne (GDY) nanosheets were added to the growth process of nickel cobalt hydrotalcite (NiCo-LDHs), which to make up for these two deficiencies of NiCo-LDHs. Due to the strong combination of NiCo-LDHs and GDY, the specific capacitance of the obtained NiCo-LDHs@GDY reaches 1284 F g −1 (1.5 times than NiCo-LDHs) under a current density of 1 A g −1 with a rate performance of 72.08 % under the current density of 20 A g −1 . In addition, the NiCo-LDHs@GDY//AC Asymmetric Supercapacitor (ASC) assembled with activated carbon demonstrates an energy density of 23.06 Wh kg −1 at a high power density of 3108.96 W kg −1 . Rejoicingly, the charge storage capacity remains at 89.53 % after 5200 charge-discharge cycles under the current density of 10 A g −1 . These outcomes show that the NiCo-LDHs@GDY electrode material has remarkable application potential and can achieve better characteristics for high-performance supercapacitors in energy storage applications .
研究领域:
材料科学
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能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2019
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IF 4.175
Yanping Zhou,Jing Li,Yang Yang,Bin Luo,Xiong Zhang,Eileen Fong,Wei Chu,Kama Huang
Two-dimensional (2D) nanostructures , though promising in energy storage, suffer from aggregation and subsequent deterioration of performance in practical applications. Hence, assembly of 2D nanostructures into three-dimensional (3D) architectures is highly desirable. Here, we report a microwave-assisted approach to the controllable synthesis of 2D materials with tunable 3D structures simply by adjusting the ratio of water/ethylene glycol (H 2 O/EG). Novel flower-on-sheet 3D hierarchical structures of nickel cobalt double hydroxide (NiCo LDHs) are obtained at EG content of 40%, while microspheres and 2D nanosheets are obtained when the EG content is 0% and 75%, respectively. We propose that under microwave irradiation, EG molecules disperse the nuclei and facilitate the initial formation of 2D sheets. Subsequently, the dominating hydrophobicity of the assembling results in the formation of nanoflowers on the sheets. When tested as electrode materials in supercapacitors , the flower-on-sheet NiCo LDH exhibits superior capacitance (1187.2 F g −1 at 1 A g −1 ), good rate capability (71% retention at 30 A g −1 ), and high stability (only 0.3% cyclic decay per cycle with respect to the first charge capacitance), which is ascribed to that ‘sheet’ could act as buffer substrate while ‘flower’ expose more active site. Our results demonstrate an energy-saving and one-pot approach for controllable construction of 2D derived 3D nanostructure that can be applied in next-generation energy storage materials .
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2019
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IF 8.355
Xinming Wu,Bin Huang,Qiguan Wang,Yan Wang
The application of two-dimensional layered hybrid materials in supercapacitor electrodes has high energy density. However, the hybrid assembly and electrochemical energy storage mechanism of multifarious layered electrode materials are still unclear. In this work, a two-dimensional interstratification assembly hybrid electrode by using electrostatic assembly between MXene modified with cetyl trimethylammonium bromide cation (CTAB) and NiCo-LDHs modified with dodecyl benzene sulfonic acid anion (DBS) is presented. As a result, the self-restacking of MXene and NiCo-LDHs nanosheets are effectively prevented, leading to a regular interstratification structure and large interlayer spacing, which accelerate diffusion of electrolyte ions and possess more electrochemical activity sites. The freestanding MXene/NiCo-LDHs electrode displays a much higher specific capacitance of 1207 F g −1 at a scan rate of 0.5 A g −1 , an impressive rate capability with 93% capacitance retention after 5000 cycles. Moreover, it shows maximum energy density of 107.3 Wh kg −1 (98.5 mWh cm −3 ) at a power density of 571 W kg −1 (524 mW cm −3 ), which is among the highest values reported for MXene and NiCo-LDHs based materials in aqueous electrolytes. This significant electrochemical performance is mainly attributed to hydration of two-dimensional electrodes and exchange or adsorption of interlayer anion-cation.
研究领域:
材料科学
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电化学
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储能
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纳米材料
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超级电容器
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
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IF 16.744
Zhaopeng Xia,Jiajun Pan,Hao Chen,Nanping Deng,Chao Yang,Xiaochen Liu,Yong Liu,Liwei Wu
Many researches are devoted to design the wearable fibrous energy storage devices with miniaturization in order to satisfy the large demand of power for portable wearable electronics. As a kind of flexible battery, one-dimensional yarn-like nickel-zinc (Ni-Zn) battery has a lot of disadvantages such as low energy density and poor power density. Significantly, metal–organic framework (MOF) material provides an opportunity to solve the preceding shortcomings due to its porous structure, excellent specific surface area and multi-functionalization. In this study, the nickel cobalt layered double hydroxides (NiCo LDHs) with triangular micro sheet array and nano sheet structure is designed and prepared on silver coated nylon fibers (SCNF) as the flexibly fibrous Ni-Zn battery cathodes (SCNF@Ni@MOF@NiCo LDHs yarn electrode), which have high specific surface area and super structure stability even during bending of the yarn. Therefore, the cathodes have abundant active sites, excellent electron conduction and fast ion diffusion. The assembled aqueous Ni-Zn battery is featured with suitable capacitance (342 mAh/g at 7.6 A/g), appropriate energy density (572.5 Wh/g at 2.59 W g −1 ) and superior stability (55 % after 5000 cycles). In addition, the obtained one-dimensional yarn-like Ni-Zn battery has excellent flexibility and high capacity retention (90 % after 1000 bends and over 80 % after different deformation ways such as bend, squeeze and twist). These fascinating results demonstrate that the SCNF@Ni@MOF@NiCo LDHs yarn electrode have great application potential in wearable energy storage devices.
研究领域:
材料科学
·
能源存储
·
纳米技术
·
可穿戴技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）