Journal of Energy Chemistry
·
2019
·
IF 5.162
Wenzhi Tian,Wenzhe Ma,Zhenyu Feng,Fang Tian,Haibo Li,Jing Liu,Shenglin Xiong
Ordered hierarchical architectures are attractive candidates for electrochemical energy storage applications. Herein, a facile self-template strategy is applied to prepare Fe 7 Se 8 architectures with a monolithic structure via a self-synthesized single precursor and subsequent calcination at high temperature. With the support of oleylamine, the precursor is structurally targeted to engineer the Fe 7 Se 8 microstructure, featuring nanorod bundles arranged along the longitudinal direction . Because of their ordered hierarchical structure, the Fe 7 Se 8 nanorod bundles deliver a high reversible capacity of 300 mAh g −1 at 0.5 A g −1 , along with exceptional rate capability up to 20 A g −1 and long-term cycle life over 8000 cycles, which represents the highest stability of Fe 7 Se 8 anodes for sodium-ion batteries reported to date. The feasibility of the present strategy to prepare metal selenide structures highlights its promising potential for the rational and effective engineering of electrode materials responsible for the electrochemical performance of energy storage systems .
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
无机化学
✓ 已验证
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Lina Wang,Yun Zhao,Yunzhen Chang,Sheng Zhu,Xingguo Qi
The construction of nano-micro scale hybrid structures by carbon materials is an effective strategy to address the issues of metal chalcogenides when used as anodes of sodium-ion batteries. Herein, we develop a carbon nanotube (CNT)-interweaved Fe 7 Se 8 /expanded graphite (EG) composite by means of a facile one-step gas-phase pyrolysis route with ferrocene , selenium and EG as the starting materials. The ex-situ monitoring of the pyrolysis process indicates that the selenium as a promoter facilitates the formation of CNTs and the carbon coated Fe 7 Se 8 nanosheet/nanorod mixture. A competing reaction between CNT growth and the evolution of Fe 7 Se 8 nanostructures occurs, which could be dominated by the concentration of selenium vapor. By optimizing the feeding ratio and the pyrolysis condition, the nanocomponents are homogeneously deposited on the surface of the EG matrix to realize a well-developed nano-micro hybrid configuration. The constructed three-dimensional conductive network, rich mesopores and high specific surface area (107.1 m 2 g −1 ) contribute to substantially enhanced sodium-storage performance in ester electrolyte. Remarkably, the optimized composite electrode exhibits high reversible capacity retention of 97.5 % after 1000 cycles at 1.0 A g −1 and improved rate performance of 325 mAh g −1 at 2.0 A g −1 . This study provides new avenues to develop high-performance metal chalcogenide electrodes for electrochemical energy storage .
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Xiangdong Guo,Jiarui Li,Yizhi Yuan,Chunyu Cui,Jian Zhu
Extensive research has been conducted on high-capacity anodes as potential replacements for graphite in lithium-ion batteries driven by the desire to achieve higher energy density. Among them, transition metal selenides have attracted much attention but suffer from poor structural stability due to the large volume expansion after Li+ insertion. In this work, we first encapsulate Fe7Se8 nanoparticles in a carbon skeleton (Fe7Se8/C) and then coat Fe7Se8/C with N-doped carbon (NC) to form a core–shell structure with a void gap created between the Fe7Se8/C core and NC shell (Fe7Se8/C-NC). The carbon skeleton alleviates the volume expansion of Fe7Se8 nanoparticles and increases the electronic conductivity, while the NC coating layer maintains the structural integrity of Fe7Se8/C and improves the electrolyte penetration. Because of this special nanostructure, the Fe7Se8/C-NC electrode shows ultrahigh capacities of 1176, 749.3, and 692.4 mAh g–1 at current densities of 0.1, 1, and 2 A g–1 and maintains high capacities of 457.8 and 324.5 mAh g–1 after 300 and 800 cycles at 2 A g–1, respectively. This multilevel protection strategy makes Fe7Se8 a promising candidate for next generation anodes and provides inspiration for the design of other anodes.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Shuang Yang,Jiangmin Jiang,Wenjie He,Langyuan Wu,Yinghong Xu,Bing Ding,Hui Dou,Xiaogang Zhang
With the associated advantages of low costs and abundant resources, sodium-ion capacitors (SICs) present a suitable means for large-scale energy storage. However, their practical application is still significantly limited by the sluggish electrochemical reaction kinetics of battery-type anodes. Herein, the nitrogen-doped carbon-encapsulated Fe 7 Se 8 nanorods (Fe 7 Se 8 @NC) with a core–shell structure were prepared via an in-situ self-polymerization and carbonization–selenization approach, which improves ion transport and maintains the structural stability of the nanorods. The designed Fe 7 Se 8 @NC nanorods exhibit desirable rate capability with a capacity of 290.7 mAh/g at 10 A/g and long-term cyclability with 84.6 % retention over 6000 cycles at 5 A/g. Moreover, research has shown that the diffusion dynamics of Na + is improved in ether-based electrolytes and that the irreversible reactions at low voltages can be inhibited by a high discharge cut-off voltage. Furthermore, we demonstrated the specific sodium storage mechanism and excellent electrochemical reversibility of the Fe 7 Se 8 @NC electrode through in-situ and ex-situ characterization techniques. As expected, the assembled SICs with the Fe 7 Se 8 @NC anode and active carbon cathode deliver prominent energy/power densities and an ultra-long cycle life over 5000 cycles, shedding new light on the design of transition metal dichalcogenides as anode materials for advanced energy storage systems.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Xiangzhong Kong,Linqing Wang,Ziyang Xi,Yong Liu,Yuheng Zhou,Zhongmin Wan,Xi Chen,Shi Li,Liya Rong
Sodium ion batteries (SIBs) has been regarded as one of the most promising large scale energy storage devices. Besides, hydrogen production by water splitting is the green, safe and low cost long-term energy conversion and storage technology. Rare studies have reported advanced electrode materials for both SIBs and HER. Herein, Fe 7 Se 8 nanoparticles have been successfully encapsulated into CNT reinforced fibrous network (Fe 7 Se 8 /CNT/C) by electrospinning combined with in situ selenide process. When utilized as flexible anodes for SIB, the Fe 7 Se 8 /CNT/C delivers superior rate capabilities (524 mAh g −1 even at 5000 mA g −1 ) and cycling stability (610 mAh g −1 at 500 mA g −1 after 1000 cycles). Moreover, the Fe 7 Se 8 /CNT/C also delivers considerable hydrogen evolution reaction (HER) activity (an overpotential of 138 mV at a current density of 10 mA cm −2 and a Tafel slope of 114 mv dec −1 ). Ex-situ electrochemical mechanism studies including EIS, GITT, CV and ECSA reveal that the graphitized CNT reinforced fibers can accelerate the ions/electrons transportations and the robust fibrous network structure guarantees excellent structural stability, thereby, preventing the aggregations of Fe 7 Se 8 nanoparticles, facilitating electrolyte penetration and creating numerous catalytic active sites. Therefore, the Fe 7 Se 8 /CNT/C is one of the most promising energy storage and conversion materials. The fabrication strategy in this work could give an insight in exploring advanced functional materials.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Jujun Yuan,Yunfei Gan,Xijun Xu,Meiqi Mu,Haishan He,Xiaokang Li,Xianke Zhang,Jun Liu
The Fe 7 Se 8 @Carbon (C) nanotubes are successfully synthesized using Fe 3 O 4 @C nanotubes as sacrificial templates. Fe 7 Se 8 @C nanotubes exhibit excellent rate behaviour and maintainable capacity (319 mAh g −1 at 2 A g −1 upon 720 cycles), when utilized as SIBs anode. Moreover, for PIBs anode, Fe 7 Se 8 @C nanotubes also exhibit outstanding rate behaviour and maintainable capacity 222 mAh g −1 at 2 A g −1 upon 500 cycles). The superior electrochemical performance of Fe 7 Se 8 @C nanotubes is ascribed to the unique structure, where the hierarchical hollow tubular characteristic of Fe 7 Se 8 @C composites can mitigate the volume expansion of Fe 7 Se 8 and supply effective transmission paths for both Na + (K + ) and electrons within repeated cycle processes, and additionally, N -doped carbon layer can further protect the integrality of Fe 7 Se 8 @C nanotubes from destruction within the cycle processes, and enhance electronic conductivity.
研究领域:
材料科学
·
储能
·
电化学
·
纳米材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）