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1.
One‐Pot Method for Synthesizing Spherical‐Like Metal Sulfide–Reduced Graphene Oxide Composite Powders with Superior Electrochemical Properties for Lithium‐Ion Batteries
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Gi Dae Park Seung Ho Choi Prof. Jung‐Kul Lee Prof. Yun Chan Kang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):12183-12189
A facile, one‐pot method for synthesizing spherical‐like metal sulfide–reduced graphene oxide (RGO) composite powders by spray pyrolysis is reported. The direct sulfidation of ZnO nanocrystals decorated on spherical‐like RGO powders resulted in ZnS–RGO composite powders. ZnS nanocrystals with a size below 20 nm were uniformly dispersed on spherical‐like RGO balls. The discharge capacities of the ZnS–RGO, ZnO–RGO, bare ZnS, and bare ZnO powders at a current density of 1000 mA g?1 after 300 cycles were 628, 476, 230, and 168 mA h g?1, respectively, and the corresponding capacity retentions measured after the first cycles were 93, 70, 40, and 21 %, respectively. The discharge capacity of the ZnS–RGO composite powders at a high current density of 4000 mA g?1 after 700 cycles was 437 mA h g?1. The structural stability of the highly conductive ZnS–RGO composite powders with ultrafine crystals during cycling resulted in excellent electrochemical properties. 相似文献
2.
Reduced Graphene Oxide‐Supported TiO2 Fiber Bundles with Mesostructures as Anode Materials for Lithium‐Ion Batteries
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Mengmeng Zhen Xiaohe Zhu Xiao Zhang Prof. Zhen Zhou Prof. Lu Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14454-14459
Although the synthesis of mesoporous materials is well established, the preparation of TiO2 fiber bundles with mesostructures, highly crystalline walls, and good thermal stability on the RGO nanosheets remains a challenge. Herein, a low‐cost and environmentally friendly hydrothermal route for the synthesis of RGO nanosheet‐supported anatase TiO2 fiber bundles with dense mesostructures is used. These mesostructured TiO2‐RGO materials are used for investigation of Li‐ion insertion properties, which show a reversible capacity of 235 mA h g?1 at 200 mA g?1 and 150 mA h g?1 at 1000 mA g?1 after 1000 cycles. The higher specific surface area of the new mesostructures and high conductive substrate (RGO nanosheets) result in excellent lithium storage performance, high‐rate performance, and strong cycling stability of the TiO2‐RGO composites. 相似文献
3.
Facile Synthesis of Nitrogen‐Containing Mesoporous Carbon for High‐Performance Energy Storage Applications
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Yunling Xu Jie Wang Zhi Chang Bing Ding Ya Wang Laifa Shen Changhuan Mi Hui Dou Prof. Xiaogang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(12):4256-4262
Porous carbon with high specific surface area (SSA), a reasonable pore size distribution, and modified surface chemistry is highly desirable for application in energy storage devices. Herein, we report the synthesis of nitrogen‐containing mesoporous carbon with high SSA (1390 m2 g?1), a suitable pore size distribution (1.5–8.1 nm), and a nitrogen content of 4.7 wt % through a facile one‐step self‐assembly process. Owing to its unique physical characteristics and nitrogen doping, this material demonstrates great promise for application in both supercapacitors and encapsulating sulfur as a superior cathode material for lithium–sulfur batteries. When deployed as a supercapacitor electrode, it exhibited a high specific capacitance of 238.4 F g?1 at 1 A g?1 and an excellent rate capability (180 F g?1, 10 A g?1). Furthermore, when an NMC/S electrode was evaluated as the cathode material for lithium–sulfur batteries, it showed a high initial discharge capacity of 1143.6 mA h g?1 at 837.5 mA g?1 and an extraordinary cycling stability with 70.3 % capacity retention after 100 cycles. 相似文献
4.
Junpeng Xie Xiaodan Li Haojie Lai Zhijuan Zhao Jinliang Li Wanggang Zhang Weiguang Xie Yiming Liu Wenjie Mai 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(41):14882-14889
Metal–organic framework‐derived NiCo2.5S4 microrods wrapped in reduced graphene oxide (NCS@RGO) were synthesized for potassium‐ion storage. Upon coordination with organic potassium salts, NCS@RGO exhibits an ultrahigh initial reversible specific capacity (602 mAh g?1 at 50 mA g?1) and ultralong cycle life (a reversible specific capacity of 495 mAh g?1 at 200 mA g?1 after 1 900 cycles over 314 days). Furthermore, the battery demonstrates a high initial Coulombic efficiency of 78 %, outperforming most sulfides reported previously. Advanced ex situ characterization techniques, including atomic force microscopy, were used for evaluation and the results indicate that the organic potassium salt‐containing electrolyte helps to form thin and robust solid electrolyte interphase layers, which reduce the formation of byproducts during the potassiation–depotassiation process and enhance the mechanical stability of electrodes. The excellent conductivity of the RGO in the composites, and the robust interface between the electrodes and electrolytes, imbue the electrode with useful properties; including, ultrafast potassium‐ion storage with a reversible specific capacity of 402 mAh g?1 even at 2 A g?1. 相似文献
5.
Dr. Fei‐Fei Zhang Dr. Gang Huang Xu‐Xu Wang Dr. Yu‐Ling Qin Dr. Xin‐Chuan Du Dong‐Ming Yin Fei Liang Prof. Li‐Min Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(52):17523-17529
Core–shell hierarchical porous carbon spheres (HPCs) were synthesized by a facile hydrothermal method and used as host to incorporate sulfur. The microstructure, morphology, and specific surface areas of the resultant samples have been systematically characterized. The results indicate that most of sulfur is well dispersed over the core area of HPCs after the impregnation of sulfur. Meanwhile, the shell of HPCs with void pores is serving as a retard against the dissolution of lithium polysulfides. This structure can enhance the transport of electron and lithium ions as well as alleviate the stress caused by volume change during the charge–discharge process. The as‐prepared HPC‐sulfur (HPC‐S) composite with 65.3 wt % sulfur delivers a high specific capacity of 1397.9 mA h g?1 at a current density of 335 mA g?1 (0.2 C) as a cathode material for lithium–sulfur (Li‐S) batteries, and the discharge capacity of the electrode could still reach 753.2 mA h g?1 at 6700 mA g?1 (4 C). Moreover, the composite electrode exhibited an excellent cycling capacity of 830.5 mA h g?1 after 200 cycles. 相似文献
6.
Zinc‐Reduced Mesoporous TiOx Li‐Ion Battery Anodes with Exceptional Rate Capability and Cycling Stability
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Woo‐Jin Song Dr. Seungmin Yoo Dr. Jung‐In Lee Jung‐Gu Han Yeonguk Son Sun‐I Kim Myoungsoo Shin Dr. Sinho Choi Prof. Ji‐Hyun Jang Prof. Jaephil Cho Prof. Nam‐Soon Choi Prof. Soojin Park 《化学:亚洲杂志》2016,11(23):3382-3388
We demonstrate a unique synthetic route for oxygen‐deficient mesoporous TiOx by a redox–transmetalation process by using Zn metal as the reducing agent. The as‐obtained materials have significantly enhanced electronic conductivity; 20 times higher than that of as‐synthesized TiO2 material. Moreover, electrochemical impedance spectroscopy (EIS) and galvanostatic intermittent titration technique (GITT) measurements are performed to validate the low charge carrier resistance of the oxygen‐deficient TiOx. The resulting oxygen‐deficient TiOx battery anode exhibits a high reversible capacity (~180 mA h g?1 at a discharge/charge rate of 1 C/1 C after 400 cycles) and an excellent rate capability (~90 mA h g?1 even at a rate of 10 C). Also, the full cell, which is coupled with a LiCoO2 cathode material, exhibits an outstanding rate capability (>75 mA h g?1 at a rate of 3.0 C) and maintains a reversible capacity of over 100 mA h g?1 at a discharge/charge of 1 C/1 C for 300 cycles. 相似文献
7.
Reduced Graphene‐Wrapped MnO2 Nanowires Self‐Inserted with Co3O4 Nanocages: Remarkable Enhanced Performances for Lithium‐Ion Anode Applications
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Qi Zhu Yunhui Li Prof. Ying Gao Prof. Xiao Wang Prof. Shuyan Song 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(20):6876-6880
A simple synthetic approach for graphene‐templated nanostructured MnO2 nanowires self‐inserted with Co3O4 nanocages is proposed in this work. The Co3O4 nanocages were penetrated in situ by MnO2 nanowires. As an anode, the as‐obtained MnO2–Co3O4–RGO composite exhibits remarkable enhanced performance compared with the MnO2–RGO and Co3O4–RGO samples. The MnO2–Co3O4–RGO electrode delivers a reversible capacity of up to 577.4 mA h g?1 after 400 cycles at 500 mA g?1 and the Coulombic efficiency of MnO2–Co3O4–RGO is about 96 %. 相似文献
8.
Electrochemical Properties of Tin Oxide Flake/Reduced Graphene Oxide/Carbon Composite Powders as Anode Materials for Lithium‐Ion Batteries
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Su Min Lee Seung Ho Choi Prof. Yun Chan Kang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(46):15203-15207
Hierarchically structured tin oxide/reduced graphene oxide (RGO)/carbon composite powders are prepared through a one‐pot spray pyrolysis process. SnO nanoflakes of several hundred nanometers in diameter and a few nanometers in thickness are uniformly distributed over the micrometer‐sized spherical powder particles. The initial discharge and charge capacities of the tin oxide/RGO/carbon composite powders at a current density of 1000 mA g?1 are 1543 and 1060 mA h g?1, respectively. The discharge capacity of the tin oxide/RGO/carbon composite powders after 175 cycles is 844 mA h g?1, and the capacity retention measured from the second cycle is 80 %. The transformation during cycling of SnO nanoflakes, uniformly dispersed in the tin oxide/RGO/carbon composite powder, into ultrafine nanocrystals results in hollow nanovoids that act as buffers for the large volume changes that occur during cycling, thereby improving the cycling and rate performances of the tin oxide/RGO/carbon composite powders. 相似文献
9.
Assembly of SnSe Nanoparticles Confined in Graphene for Enhanced Sodium‐Ion Storage Performance
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Dr. Xu Yang Dr. Rongyu Zhang Dr. Nan Chen Dr. Xing Meng Peilei Yang Prof. Chunzhong Wang Dr. Yaoqing Zhang Prof. Yingjin Wei Prof. Gang Chen Dr. Fei Du 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1445-1451
Sodium‐ion batteries (SIBs) have attracted much interest as a low‐cost and environmentally benign energy storage system, but more attention is justifiably required to address the major technical issues relating to the anode materials to deliver high reversible capacity, superior rate capability, and stable cyclability. A SnSe/reduced graphene oxide (RGO) nanocomposite has been prepared by a facile ball‐milling method, and its structural, morphological, and electrochemical properties have been characterized and compared with those of the bare SnSe material. Although the redox behavior of SnSe remains nearly unchanged upon the incorporation of RGO, its electrochemical performance is significantly enhanced, as reflected by a high specific capacity of 590 mA h g?1 at 0.050 A g?1, a rate capability of 260 mA h g?1 at 10 A g?1, and long‐term stability over 120 cycles. This improvement may be attributed to the high electronic conductivity of RGO, which also serves as a matrix to buffer changes in volume and maintain the mechanical integrity of the electrode during (de)sodiation processes. In view of its excellent Na+ storage performance, this SnSe/RGO nanocomposite has potential as an anode material for SIBs. 相似文献
10.
《化学:亚洲杂志》2017,12(17):2284-2290
This work demonstrates a facile in situ synthesis of cobalt–manganese mixed sulfide (CoMn‐S) nanocages on reduced graphene oxide (RGO) sheets by using a crystalline Co–Mn precursor as the sacrificial template. The CoMn‐S/RGO hybrid was applied as the anode for Li‐ion storage and exhibited superior specific capacity, excellent cycling performance, and great rate capability. In particular, lithium storage testing revealed that the hybrid delivered high discharge–charge capacities of 670 mA h g−1 at 1.0 A g−1 after 400 cycles and 925 mA h g−1 at 0.1 A g−1 after 300 cycles. The outstanding electrochemical performance of CoMn‐S/RGO is attributed to the close entanglement of nanocages with RGO nanosheets achieved by the synthetic method, which greatly improves ion/electron transport along the interfaces and efficiently mitigates volume dilation during lithium reactions. This rational design of both the composition and architecture of mixed metal sulfides can be expanded to other composite systems for high‐capacity Li‐ion batteries and provides a unique insight into the development of advanced hybrid electrode materials. 相似文献
11.
Cong Li Rui Zang Pengxin Li Zengming Man Shijian Wang Xuemei Li Yuhan Wu Shuaishuai Liu Prof. Guoxiu Wang 《化学:亚洲杂志》2018,13(3):342-349
Prussian blue and its analogues (PBAs) have been recognized as one of the most promising cathode materials for room‐temperature sodium‐ion batteries (SIBs). Herein, we report high crystalline and Na‐rich Prussian white Na2CoFe(CN)6 nanocubes synthesized by an optimized and facile co‐precipitation method. The influence of crystallinity and sodium content on the electrochemical properties was systematically investigated. The optimized Na2CoFe(CN)6 nanocubes exhibited an initial capacity of 151 mA h g?1, which is close to its theoretical capacity (170 mA h g?1). Meanwhile, the Na2CoFe(CN)6 cathode demonstrated an outstanding long‐term cycle performance, retaining 78 % of its initial capacity after 500 cycles. Furthermore, the Na2CoFe(CN)6 Prussian white nanocubes also achieved a superior rate capability (115 mA h g?1 at 400 mA g?1, 92 mA h g?1 at 800 mA g?1). The enhanced performances could be attributed to the robust crystal structure and rapid transport of Na ions through large channels in the open‐framework. Most noteworthy, the as‐prepared Na2CoFe(CN)6 nanocubes are not only low‐cost in raw materials but also contain a rich sodium content (1.87 Na ions per lattice unit cell), which will be favorable for full cell fabrication and large‐scale electric storage applications. 相似文献
12.
Yuanchun Ji Prof. Carsten Streb Prof. Yu‐Fei Song 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(51):18799-18804
An organo‐functionalized polyoxometalate (POM)–pyrene hybrid (Py‐Anderson) has been used for noncovalent functionalization of carbon nanotubes (CNTs) to give a Py‐Anderson‐CNT nanocomposite through π–π interactions. The as‐synthesized nanocomposite was used as the anode material for lithium‐ion batteries, and shows higher discharge capacities and better rate capacity and cycling stability than the individual components. When the current density was 0.5 mA cm?2, the nanocomposite exhibited an initial discharge capacity of 1898.5 mA h g?1 and a high discharge capacity of 665.3 mA h g?1 for up to 100 cycles. AC impedance spectroscopy provides insight into the electrochemical properties and the charge‐transfer mechanism of the Py‐Anderson‐CNTs electrode. 相似文献
13.
Synthesis of Mesoporous Wall‐Structured TiO2 on Reduced Graphene Oxide Nanosheets with High Rate Performance for Lithium‐Ion Batteries
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Mengmeng Zhen Meiqing Sun Prof. Guandao Gao Prof. Lu Liu Prof. Zhen Zhou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5317-5322
Mesoporous wall‐structured TiO2 on reduced graphene oxide (RGO) nanosheets were successfully fabricated through a simple hydrothermal process without any surfactants and annealed at 400 °C for 2 h under argon. The obtained mesoporous structured TiO2–RGO composites had a high surface area (99 0307 m2 g?1) and exhibited excellent electrochemical cycling (a reversible capacity of 260 mAh g?1 at 1.2 C and 180 mAh g?1 at 5 C after 400 cycles), demonstrating it to be a promising method for the development of high‐performance Li‐ion batteries. 相似文献
14.
K2Mn4O8/Reduced Graphene Oxide Nanocomposites for Excellent Lithium Storage and Adsorption of Lead Ions
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Shu‐Meng Hao Prof. Jin Qu Jing Yang Chen‐Xi Gui Qian‐Qian Wang Qian‐Jie Li Prof. Xiaofeng Li Prof. Zhong‐Zhen Yu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(10):3397-3404
Ion diffusion efficiency at the solid–liquid interface is an important factor for energy storage and adsorption from aqueous solution. Although K2Mn4O8 (KMO) exhibits efficient ion diffusion and ion‐exchange capacities, due to its high interlayer space of 0.70 nm, how to enhance its mass transfer performance is still an issue. Herein, novel layered KMO/reduced graphene oxide (RGO) nanocomposites are fabricated through the anchoring of KMO nanoplates on RGO with a mild solution process. The face‐to‐face structure facilitates fast transfer of lithium and lead ions; thus leading to excellent lithium storage and lead ion adsorption. The anchoring of KMO on RGO not only increases electrical conductivity of the layered nanocomposites, but also effectively prevents aggregation of KMO nanoplates. The KMO/RGO nanocomposite with an optimal RGO content exhibits a first cycle charge capacity of 739 mA h g?1, which is much higher than that of KMO (326 mA h g?1). After 100 charge–discharge cycles, it still retains a charge capacity of 664 mA h g?1. For the adsorption of lead ions, the KMO/RGO nanocomposite exhibits a capacity of 341 mg g?1, which is higher than those of KMO (305 mg g?1) and RGO (63 mg g?1) alone. 相似文献
15.
Dual‐Confined Sulfur Nanoparticles Encapsulated in Hollow TiO2 Spheres Wrapped with Graphene for Lithium–Sulfur Batteries
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Haining Fan Dr. Qunli Tang Prof. Xiaohua Chen Dr. Binbin Fan Shanliang Chen Dr. Aiping Hu 《化学:亚洲杂志》2016,11(20):2911-2917
Lithium–sulfur (Li?S) batteries are attractive owing to their higher energy density and lower cost compared with the universally used lithium‐ion batteries (LIBs), but there are some problems that stop their practical use, such as low utilization and rapid capacity‐fading of the sulfur cathode, which is mainly caused by the shuttle effect, and the uncontrollable deposition of lithium sulfide species. Herein, we report the design and fabrication of dual‐confined sulfur nanoparticles that were encapsulated inside hollow TiO2 spheres; the encapsulated nanoparticles were prepared by a facile hydrolysis process combined with acid etching, followed by “wrapping” with graphene (G?TiO2@S). In this unique composite architecture, the hollow TiO2 spheres acted as effective sulfur carriers by confining the polysulfides and buffering volume changes during the charge‐discharge processes by means of physical force from the hollow spheres and chemical binding between TiO2 and the polysulfides. Moreover, the graphene‐wrapped skin provided an effective 3D conductive network to improve the electronic conductivity of the sulfur cathode and, at the same time, to further suppress the dissolution of the polysulfides. As results, the G?TiO2@S hybrids exhibited a high and stable discharge capacity of up to 853.4 mA h g?1 over 200 cycles at 0.5 C (1 C=1675 mA g?1) and an excellent rate capability of 675 mA h g?1 at a current rate of 2 C; thus, G?TiO2@S holds great promise as a cathode material for Li?S batteries. 相似文献
16.
Shunqi Xu Gang Wang Bishnu P. Biswal Matthew Addicoat Silvia Paasch Wenbo Sheng Xiaodong Zhuang Eike Brunner Thomas Heine Reinhard Berger Xinliang Feng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(3):859-863
A two‐dimensional (2D) sp2‐carbon‐linked conjugated polymer framework (2D CCP‐HATN) has a nitrogen‐doped skeleton, a periodical dual‐pore structure and high chemical stability. The polymer backbone consists of hexaazatrinaphthalene (HATN) and cyanovinylene units linked entirely by carbon–carbon double bonds. Profiting from the shape‐persistent framework of 2D CCP‐HATN integrated with the electrochemical redox‐active HATN and the robust sp2 carbon‐carbon linkage, 2D CCP‐HATN hybridized with carbon nanotubes shows a high capacity of 116 mA h g?1, with high utilization of its redox‐active sites and superb cycling stability (91 % after 1000 cycles) and rate capability (82 %, 1.0 A g?1 vs. 0.1 A g?1) as an organic cathode material for lithium‐ion batteries. 相似文献
17.
Electrochemical and Structural Study of Layered P2‐Type Na2/3Ni1/3Mn2/3O2 as Cathode Material for Sodium‐Ion Battery
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Yanfen Wen Dr. Bei Wang Guang Zeng Prof. Kazuhiro Nogita Delai Ye Prof. Lianzhou Wang 《化学:亚洲杂志》2015,10(3):661-666
P2‐type Na2/3Ni1/3Mn2/3O2 was synthesized by a controlled co‐precipitation method followed by a high‐temperature solid‐state reaction and was used as a cathode material for a sodium‐ion battery (SIB). The electrochemical behavior of this layered material was studied and an initial discharge capacity of 151.8 mA h g?1 was achieved in the voltage range of 1.5–3.75 V versus Na+/Na. The retained discharge capacity was found to be 123.5 mA h g?1 after charging/discharging 50 cycles, approximately 81.4 % of the initial discharge capacity. In situ X‐ray diffraction analysis was used to investigate the sodium insertion and extraction mechanism and clearly revealed the reversible structural changes of the P2‐Na2/3Ni1/3Mn2/3O2 and no emergence of the O2‐Ni1/3Mn2/3O2 phase during the cycling test, which is important for designing stable and high‐performance SIB cathode materials. 相似文献
18.
TiO2–B Nanosheets/Anatase Nanocrystals Co‐Anchored on Nanoporous Graphene: In Situ Reduction–Hydrolysis Synthesis and Their Superior Rate Performance as an Anode Material
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Chaoji Chen Prof. Xianluo Hu Yan Jiang Ze Yang Pei Hu Prof. Yunhui Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(5):1383-1388
A unique hybrid, TiO2–B nanosheets/anatase nanocrystals co‐anchored on nanoporous graphene sheets, can be synthesized by a facile microwave‐induced in situ reduction–hydrolysis route. The as‐formed nanohybrid has a hierarchically porous structure, involving both mesopores of approximately 4 nm and meso‐/macropores of 30–60 nm in the graphene sheets, and a large surface area. Importantly, electrodes composed of the nanohybrid exhibit superior rate capability (160 mA h g?1 at ca. 36 C; 154 mA h g?1 at ca. 72 C) and excellent cyclability. The synergistic effects of conductive graphene with numerous nanopores and the pseudocapacitive effect of ultrafine TiO2–B nanosheets and anatase nanocrystals endow the hybrid a superior rate capability. 相似文献
19.
Facile Mechanochemical Synthesis of Nano SnO2/Graphene Composite from Coarse Metallic Sn and Graphite Oxide: An Outstanding Anode Material for Lithium‐Ion Batteries
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Fei Ye Bote Zhao Prof. Ran Ran Prof. Zongping Shao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(14):4055-4063
A facile method for the large‐scale synthesis of SnO2 nanocrystal/graphene composites by using coarse metallic Sn particles and cheap graphite oxide (GO) as raw materials is demonstrated. This method uses simple ball milling to realize a mechanochemical reaction between Sn particles and GO. After the reaction, the initial coarse Sn particles with sizes of 3–30 μm are converted to SnO2 nanocrystals (approximately 4 nm) while GO is reduced to graphene. Composite with different grinding times (1 h 20 min, 2 h 20 min or 8 h 20 min, abbreviated to 1, 2 or 8 h below) and raw material ratios (Sn:GO, 1:2, 1:1, 2:1, w/w) are investigated by X‐ray diffraction, X‐ray photoelectron spectroscopy, field‐emission scanning electron microscopy and transmission electron microscopy. The as‐prepared SnO2/graphene composite with a grinding time of 8 h and raw material ratio of 1:1 forms micrometer‐sized architected chips composed of composite sheets, and demonstrates a high tap density of 1.53 g cm?3. By using such composites as anode material for LIBs, a high specific capacity of 891 mA h g?1 is achieved even after 50 cycles at 100 mA g?1. 相似文献
20.
Lithium‐Rich Layered Oxide Li1.18Ni0.15Co0.15Mn0.52O2 as the Cathode Material for Hybrid Sodium‐Ion Batteries
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Zhixuan Wei Dr. Yu Gao Lei Wang Chaoyang Zhang Xiaofei Bian Qiang Fu Prof. Chunzhong Wang Prof. Yingjin Wei Dr. Fei Du Prof. Gang Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(33):11610-11616
Li‐rich layered oxide Li1.18Ni0.15Co0.15Mn0.52O2 (LNCM) is, for the first time, examined as the positive electrode for hybrid sodium‐ion battery and its Na+ storage properties are comprehensively studied in terms of galvanostatic charge–discharge curves, cyclic voltammetry and rate capability. LNCM in the proposed sodium‐ion battery demonstrates good rate capability whose discharge capacity reaches about 90 mA h g?1 at 10 C rate and excellent cycle stability with specific capacity of about 105 mA h g?1 for 200 cycles at 5 C rate. Moreover, ex situ ICP‐OES suggests interesting mixed‐ions migration processes: In the initial two cycles, only Li+ can intercalate into the LNCM cathode, whereas both Li+ and Na+ work together as the electrochemical cycles increase. Also the structural evolution of LNCM is examined in terms of ex situ XRD pattern at the end of various charge–discharge scans. The strong insight obtained from this study could be beneficial to the design of new layered cathode materials for future rechargeable sodium‐ion batteries. 相似文献