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1.
Songwei Gao Nü Wang Shuai Li Dianming Li Zhimin Cui Guichu Yue Jingchong Liu Xiaoxian Zhao Lei Jiang Yong Zhao 《Angewandte Chemie (International ed. in English)》2020,59(6):2465-2472
Multi‐wall Sn/SnO2@carbon hollow nanofibers evolved from SnO2 nanofibers are designed and programable synthesized by electrospinning, polypyrrole coating, and annealing reduction. The synthesized hollow nanofibers have a special wire‐in‐double‐wall‐tube structure with larger specific surface area and abundant inner spaces, which can provide effective contacting area of electrolyte with electrode materials and more active sites for redox reaction. It shows excellent cycling stability by virtue of effectively alleviating pulverization of tin‐based electrode materials caused by volume expansion. Even after 2000 cycles, the wire‐in‐double‐wall‐tube Sn/SnO2@carbon nanofibers exhibit a high specific capacity of 986.3 mAh g?1 (1 A g?1) and still maintains 508.2 mAh g?1 at high current density of 5 A g?1. This outstanding electrochemical performance suggests the multi‐wall Sn/SnO2@ carbon hollow nanofibers are great promising for high performance energy storage systems. 相似文献
2.
Juan Li Shuang Hou Tiezhong Liu Liangke Wang Chen Mei Yayun Guo Prof. Lingzhi Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):2013-2024
Improving the performance of anode materials for lithium-ion batteries (LIBs) is a hotly debated topic. Herein, hollow Ni−Co skeleton@MoS2/MoO3 nanocubes (NCM-NCs), with an average size of about 193 nm, have been synthesized through a facile hydrothermal reaction. Specifically, MoO3/MoS2 composites are grown on Ni−Co skeletons derived from nickel–cobalt Prussian blue analogue nanocubes (Ni−Co PBAs). The Ni−Co PBAs were synthesized through a precipitation method and utilized as self-templates that provided a larger specific surface area for the adhesion of MoO3/MoS2 composites. According to Raman spectroscopy results, as-obtained defect-rich MoS2 is confirmed to be a metallic 1T-phase MoS2. Furthermore, the average particle size of Ni−Co PBAs (≈43 nm) is only about one-tenth of the previously reported particle size (≈400 nm). If assessed as anodes of LIBs, the hollow NCM-NC hybrids deliver an excellent rate performance and superior cycling performance (with an initial discharge capacity of 1526.3 mAh g−1 and up to 1720.6 mAh g−1 after 317 cycles under a current density of 0.2 A g−1). Meanwhile, ultralong cycling life is retained, even at high current densities (776.6 mAh g−1 at 2 A g−1 after 700 cycles and 584.8 mAh g−1 at 5 A g−1 after 800 cycles). Moreover, at a rate of 1 A g−1, the average specific capacity is maintained at 661 mAh g−1. Thus, the hierarchical hollow NCM-NC hybrids with excellent electrochemical performance are a promising anode material for LIBs. 相似文献
3.
Hierarchical SnO2/Carbon Nanofibrous Composite Derived from Cellulose Substance as Anode Material for Lithium‐Ion Batteries
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Mengya Wang Shun Li Dr. Yiming Zhang Prof. Jianguo Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(45):16195-16202
A hierarchical fibrous SnO2/carbon nanocomposite composed of fine SnO2 nanocrystallites immobilized as a thin layer on a carbon nanofiber surface was synthesized employing natural cellulose substance as both scaffold and carbon source. It was achieved by calcination/carbonization of the as‐deposited SnO2‐gel/cellulose hybrid in an argon atmosphere. As being employed as an anode material for lithium‐ion batteries, the porous structures, small SnO2 crystallite sizes, and the carbon buffering matrix possessed by the nanocomposite facilitate the electrode–electrolyte contact, promote the electron transfer and Li+ diffusion, and relieve the severe volume change and aggregation of the active particles during the charge/discharge cycles. Hence, the nanocomposite showed high reversible capacity, significant cycling stability, and rate capability that are superior to the nanotubular SnO2 and SnO2 sol–gel powder counter materials. For such a composite with 27.8 wt % SnO2 content and 346.4 m2 g?1 specific surface area, a capacity of 623 mAh g?1 was delivered after 120 cycles at 0.2 C. Further coating of the SnO2/carbon nanofibers with an additional carbon layer resulted in an improved cycling stability and rate performance. 相似文献
4.
Dr. Ming Chen Dr. Ping Xiao Ke Yang Boxu Dong Dong Xu Changyu Yan Xuejiao Liu Jiantao Zai Prof. CheeTong John Low Prof. Xuefeng Qian 《Angewandte Chemie (International ed. in English)》2023,62(16):e202219177
With a theoretical capacity of 847 mAh g−1, Sn has emerged as promising anode material for sodium-ion batteries (SIBs). However, enormous volume expansion and agglomeration of nano Sn lead to low Coulombic efficiency and poor cycling stability. Herein, an intermetallic FeSn2 layer is designed via thermal reduction of polymer-Fe2O3 coated hollow SnO2 spheres to construct a yolk-shell structured Sn/FeSn2@C. The FeSn2 layer can relieve internal stress, avoid the agglomeration of Sn to accelerate the Na+ transport, and enable fast electronic conduction, which endows quick electrochemical dynamics and long-term stability. As a result, the Sn/FeSn2@C anode exhibits high initial Coulombic efficiency (ICE=93.8 %) and a high reversible capacity of 409 mAh g−1 at 1 A g−1 after 1500 cycles, corresponding to an 80 % capacity retention. In addition, NVP//Sn/FeSn2@C sodium-ion full cell shows outstanding cycle stability (capacity retaining rate of 89.7 % after 200 cycles at 1 C). 相似文献
5.
Bo Wang Dr. Wencheng Du Dr. Yang Yang Dr. Yufei Zhang Dr. Qi Zhang Prof. Xianhong Rui Dr. Hongbo Geng Prof. Cheng Chao Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6554-6560
Lithium ion batteries (LIBs) at present still suffer from low rate capability and poor cycle life during fast ion insertion/extraction processes. Searching for high-capacity and stable anode materials is still an ongoing challenge. Herein, a facile strategy for the synthesis of ultrathin GeS2 nanosheets with the thickness of 1.1 nm is reported. When used as anodes for LIBs, the two-dimensional (2D) structure can effectively increase the electrode/electrolyte interface area, facilitate the ion transport, and buffer the volume expansion. Benefiting from these merits, the as-synthesized GeS2 nanosheets deliver high specific capacity (1335 mAh g−1 at 0.15 A g−1), extraordinary rate performance (337 mAh g−1 at 15 A g−1) and stable cycling performance (974 mAh g−1 after 200 cycles at 0.5 A g−1). Importantly, our fabricated Li-ion full cells manifest an impressive specific capacity of 577 mAh g−1 after 50 cycles at 0.1 A g−1 and a high energy density of 361 Wh kg−1 at a power density of 346 W kg−1. Furthermore, the electrochemical reaction mechanism is investigated by the means of ex-situ high-resolution transmission electron microscopy. These results suggest that GeS2 can use to be an alternative anode material and encourage more efforts to develop other high-performance LIBs anodes. 相似文献
6.
Haiming Li Dr. Tailin Wang Dr. Xue Wang Prof. Guangda Li Prof. Jianxing Shen Prof. Jinling Chai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(35):9022-9030
We have successfully synthesized Na2FePO4F/biocarbon nanocomposite hollow microspheres from FeIII precursor as cathodes for sodium-ion batteries through self-assembly of yeast cell biotemplate and sol-gel technology. The carbon coating on the nanoparticle surface with a mesoporous structure enhances electron diffusion into Na2FePO4F crystal particles. The improved electrochemical performance of Na2FePO4F/biocarbon nanocomposites is attributed to the larger electrode−electrolyte contact area and more active sites for Na+ on the surface of hollow microspheres compared with those of Na2FePO4F/C. The Na2FePO4F/biocarbon nanocomposite exhibits a high initial discharge capacity of 114.3 mAh g−1 at 0.1 C, long-cycle stability with a capacity retention of 74.3 % after 500 cycles at 5 C, and excellent rate capability (70.2 mAh g−1 at 5 C) compared with Na2FePO4F/C. This novel nanocomposite hollow microsphere structure is suitable for improving the property of other cathode materials for high-power batteries. 相似文献
7.
Dr. Sourav Khan Dr. Rayappan Pavul Raj Dr. Laurel George Dr. G. S. Kamali Kannangara Dr. Adriyan Milev Prof. Dr. Upadhyayula V. Varadaraju Prof. Dr. Parasuraman Selvam 《ChemistryOpen》2020,9(1):23-31
The synthesis of morphology-controlled carbon-coated nanostructured LiFePO4 (LFP/Carbon) cathode materials by surfactant-assisted hydrothermal method using block copolymers is reported. The resulting nanocrystalline high surface area materials were coated with carbon and designated as LFP/C123 and LFP/C311. All the materials were systematically characterized by various analytical, spectroscopic and imaging techniques. The reverse structure of the surfactant Pluronic® 31R1 (PPO-PEO-PPO) in comparison to Pluronic® P123 (PEO-PPO-PEO) played a vital role in controlling the particle size and morphology which in turn ameliorate the electrochemical performance in terms of reversible specific capacity (163 mAh g−1 and 140 mAh g−1 at 0.1 C for LFP/C311 and LFP/C123, respectively). In addition, LFP/C311 demonstrated excellent electrochemical performance including lower charge transfer resistance (146.3 Ω) and excellent cycling stability (95 % capacity retention at 1 C after 100 cycles) and high rate capability (163.2 mAh g−1 at 0.1 C; 147.1 mAh g−1 at 1 C). The better performance of the former is attributed to LFP nanoparticles (<50 nm) with a specific spindle-shaped morphology. Further, we have also evaluated the electrode performance with the use of both PVDF and CMC binders employed for the electrode fabrication. 相似文献
8.
Qiongguang Li Dr. Yanhong Wang Dr. Qiangqiang Tan Dr. Ziyi Zhong Dr. Fabing Su 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(56):12882-12890
To overcome the drawbacks of the structural instability and poor conductivity of SnO2-based anode materials, a hollow core–shell-structured SnO2@C@Co-NC (NC=N-doped carbon) composite was designed and synthesized by employing the heteroatom-doping and multiconfinement strategies. This composite material showed a much-reduced resistance to charge transfer and excellent cycling performance compared to the bare SnO2 nanoparticles and SnO2@C composites. The doped heteroatoms and heterostructure boost the charge transfer, and the porous structure shortens the Li-ion diffusion pathway. Also, the volume expansion of SnO2 NPs is accommodated by the hollow space and restricted by the multishell heteroatom-doped carbon framework. As a result, this structured anode material delivered a high initial capacity of 1559.1 mA h g−1 at 50 mA g−1 and an initial charge capacity of 627.2 mA h g−1 at 500 mA g−1. Moreover, the discharge capacity could be maintained at 410.8 mA h g−1 after 500 cycles with an attenuation rate of only 0.069 % per cycle. This multiconfined SnO2@C@Co-NC structure with superior energy density and durable lifespan is highly promising for the next-generation lithium-ion batteries. 相似文献
9.
Robust SnO2−x Nanoparticle‐Impregnated Carbon Nanofibers with Outstanding Electrochemical Performance for Advanced Sodium‐Ion Batteries
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Dingtao Ma Dr. Yongliang Li Dr. Hongwei Mi Shan Luo Prof. Peixin Zhang Prof. Zhiqun Lin Prof. Jianqing Li Prof. Han Zhang 《Angewandte Chemie (International ed. in English)》2018,57(29):8901-8905
The sluggish sodium reaction kinetics, unstable Sn/Na2O interface, and large volume expansion are major obstacles that impede practical applications of SnO2‐based electrodes for sodium‐ion batteries (SIBs). Herein, we report the crafting of homogeneously confined oxygen‐vacancy‐containing SnO2?x nanoparticles with well‐defined void space in porous carbon nanofibers (denoted SnO2?x/C composites) that address the issues noted above for advanced SIBs. Notably, SnO2?x/C composites can be readily exploited as the working electrode, without need for binders and conductive additives. In contrast to past work, SnO2?x/C composites‐based SIBs show remarkable electrochemical performance, offering high reversible capacity, ultralong cyclic stability, and excellent rate capability. A discharge capacity of 565 mAh g?1 at 1 A g?1 is retained after 2000 cycles. 相似文献
10.
Organic carbonyl electrode materials are widely employed for alkali metal-ion secondary batteries in terms of their sustainability, structure designability and abundant resources. As a typical redox-active organic electrode materials, pyrene-4, 5, 9, 10-tetraone (PT) shows high theoretical capacity due to the rich carbonyl active sites. But its electrochemical behavior in secondary batteries still needs further exploration. Herein, PT-based linear polymers (PPTS) is synthesized with thioether bond as bridging group and then employed as an anode material for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). As expected, PPTS shows improved conductivity and insolubility in the non-aqueous electrolyte. When used as an anode material for LIBs, PPTS delivers a high reversible specific capacity of 697.1 mAh g−1 at 0.1 A g−1 and good rate performance (335.4 mAh g−1 at 1 A g−1). Moreover, a reversible specific capacity of 205.2 mAh g−1 at 0.05 A g−1 could be obtained as an anode material for SIBs. 相似文献
11.
Cheng Zheng Deluo Ji Qian Yao Prof. Zhongchao Bai Yansong Zhu Chuanhao Nie Prof. Duo Liu Prof. Nana Wang Prof. Jian Yang Prof. Shixue Dou 《Angewandte Chemie (International ed. in English)》2023,62(14):e202214258
The applications of alloy-type anode materials for Na-ion batteries are always obstructed by enormous volume variation upon cycles. Here, K+ ions are introduced as an electrolyte additive to improve the electrochemical performance via electrostatic shielding, using Sn microparticles (μ-Sn) as a model. Theoretical calculations and experimental results indicate that K+ ions are not incorporated in the electrode, but accumulate on some sites. This accumulation slows down the local sodiation at the “hot spots”, promotes the uniform sodiation and enhances the electrode stability. Therefore, the electrode maintains a high specific capacity of 565 mAh g−1 after 3000 cycles at 2 A g−1, much better than the case without K+. The electrode also remains an areal capacity of ≈3.5 mAh cm−2 after 100 cycles. This method does not involve time-consuming preparation, sophisticated instruments and expensive reagents, exhibiting the promising potential for other anode materials. 相似文献
12.
Multiple Ambient Hydrolysis Deposition of Tin Oxide into Nanoporous Carbon To Give a Stable Anode for Lithium‐Ion Batteries
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Dr. Vadivukarasi Raju Xingfeng Wang Dr. Wei Luo Prof. Xiulei Ji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(25):7686-7691
A novel ambient hydrolysis deposition (AHD) methodology that employs sequential water adsorption followed by a hydrolysis reaction to infiltrate SnO2 nanoparticles into the nanopores of mesoporous carbon in a conformal and controllable manner is introduced. The empty space in the SnO2/C composites can be adjusted by varying the number of AHD cycles. An SnO2/C composite with an intermediate SnO2 loading exhibited an initial specific delithiation capacity of 1054 mAh g?1 as an anode for Li‐ion batteries. The capacity contribution from SnO2 in the composite electrode approaches the theoretical capacity of SnO2 (1494 mAh g?1) if both Sn alloying and SnO2 conversion reactions are considered to be reversible. The composite shows a specific capacity of 573 mAh g?1 after 300 cycles, that is, one of the most stable cycling performances for SnO2/mesoporous carbon composites. The results demonstrated the importance of well‐tuned empty space in nanostructured composites to accommodate expansion of the electrode active mass during alloying/dealloying and conversion reactions. 相似文献
13.
Dr. Honghong Fan Dr. Farzaneh Bahmani Dr. Yusuf Valentino Kaneti Dr. Yanna Guo Prof. Asma A. Alothman Prof. Xinglong Wu Prof. Yusuke Yamauchi Prof. Wenliang Li Prof. Jingping Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(60):13652-13658
Binary transition-metal oxides (BTMOs) with hierarchical micro–nano-structures have attracted great interest as potential anode materials for lithium-ion batteries (LIBs). Herein, we report the fabrication of hierarchical cauliflower-like CoFe2O4 (cl-CoFe2O4) via a facile room-temperature co-precipitation method followed by post-synthetic annealing. The obtained cauliflower structure is constructed by the assembly of microrods, which themselves are composed of small nanoparticles. Such hierarchical micro–nano-structure can promote fast ion transport and stable electrode–electrolyte interfaces. As a result, the cl-CoFe2O4 can deliver a high specific capacity (1019.9 mAh g−1 at 0.1 A g−1), excellent rate capability (626.0 mAh g−1 at 5 A g−1), and good cyclability (675.4 mAh g−1 at 4 A g−1 for over 400 cycles) as an anode material for LIBs. Even at low temperatures of 0 °C and −25 °C, the cl-CoFe2O4 anode can deliver high capacities of 907.5 and 664.5 mAh g−1 at 100 mA g−1, respectively, indicating its wide operating temperature. More importantly, the full-cell assembled with a commercial LiFePO4 cathode exhibits a high rate performance (214.2 mAh g−1 at 5000 mA g−1) and an impressive cycling performance (612.7 mAh g−1 over 140 cycles at 300 mA g−1) in the voltage range of 0.5–3.6 V. Kinetic analysis reveals that the electrochemical performance of cl-CoFe2O4 is dominated by pseudocapacitive behavior, leading to fast Li+ insertion/extraction and good cycling life. 相似文献
14.
Dr. Guiying Tian Chuanfeng Huang Xianlin Luo Dr. Zijian Zhao Yong Peng Yuqin Gao Dr. Na Tang Dr. Sonia Dsoke 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(55):13774-13782
Owing to their high specific capacity and abundant reserve, CuxS compounds are promising electrode materials for lithium-ion batteries (LIBs). Carbon compositing could stabilize the CuxS structure and repress capacity fading during the electrochemical cycling, but the corresponding Li+ storage mechanism and stabilization effect should be further clarified. In this study, nanoscale Cu2S was synthesized by CuS co-precipitation and thermal reduction with polyelectrolytes. High-temperature synchrotron radiation diffraction was used to monitor the thermal reduction process. During the first cycle, the conversion mechanism upon lithium storage in the Cu2S/carbon was elucidated by operando synchrotron radiation diffraction and in situ X-ray absorption spectroscopy. The N-doped carbon-composited Cu2S (Cu2S/C) exhibits an initial discharge capacity of 425 mAh g−1 at 0.1 A g−1, with a higher, long-term capacity of 523 mAh g−1 at 0.1 A g−1 after 200 cycles; in contrast, the bare CuS electrode exhibits 123 mAh g−1 after 200 cycles. Multiple-scan cyclic voltammetry proves that extra Li+ storage can mainly be ascribed to the contribution of the capacitive storage. 相似文献
15.
Ting Quan Dr. Nicolas Goubard-Bretesché Dr. Eneli Härk Dr. Zdravko Kochovski Dr. Shilin Mei Prof. Dr. Nicola Pinna Prof. Dr. Matthias Ballauff Prof. Dr. Yan Lu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(18):4757-4766
MoS2, a typical layered transition-metal dichalcogenide, is promising as an electrode material in supercapacitors. However, its low electrical conductivity could lead to limited capacitance if applied in electrochemical devices. Herein, a new nanostructure composed of hollow carbon–MoS2–carbon was successfully synthesized through an l -cysteine-assisted hydrothermal method by using gibbsite as a template and polydopamine as a carbon precursor. After calcination and etching of the gibbsite template, uniform hollow platelets, which were made of a sandwich-like assembly of partial graphitic carbon and two-dimensional layered MoS2 flakes, were obtained. The platelets showed excellent dispersibility and stability in water, and good electrical conductivity due to carbon provided by the calcination of polydopamine coatings. The hollow nanoplate morphology of the material provided a high specific surface area of 543 m2 g−1, a total pore volume of 0.677 cm3 g−1, and fairly small mesopores (≈5.3 nm). The material was applied in a symmetric supercapacitor and exhibited a specific capacitance of 248 F g−1 (0.12 F cm−2) at a constant current density of 0.1 A g−1; thus suggesting that hollow carbon–MoS2–carbon nanoplates are promising candidate materials for supercapacitors. 相似文献
16.
One-dimensional (1-D) carbon nanofibers anchored with partially reduced SnO2 nanoparticles (SnO2/Sn@C) were successfully synthesized through a simple electrospinning method followed by carbon coating and thermal reduction processes. The partially reduced Sn frameworks, combined with the carbon fibers, provide a more favorable mechanism for sodiation/desodiation than SnO2. As a result, SnO2/Sn@C exhibits a high reversible capacity (536 mAh g− 1 after 50 cycles) and an excellent rate capability (396 mAh g− 1 even at 2 C rate) when evaluated as an anode material for sodium-ion batteries (SIBs). 相似文献
17.
Yu Ming Chen Zhen Li Xiong Wen Lou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(36):10667-10670
A simple and versatile method for general synthesis of uniform one‐dimensional (1D) MxCo3−xS4 (M=Ni, Mn, Zn) hollow tubular structures (HTSs), using soft polymeric nanofibers as a template, is described. Fibrous core–shell polymer@M‐Co acetate hydroxide precursors with a controllable molar ratio of M/Co are first prepared, followed by a sulfidation process to obtain core–shell polymer@MxCo3−xS4 composite nanofibers. The as‐made MxCo3−xS4 HTSs have a high surface area and exhibit exceptional electrochemical performance as electrode materials for hybrid supercapacitors. For example, the MnCo2S4 HTS electrode can deliver specific capacitance of 1094 F g−1 at 10 A g−1, and the cycling stability is remarkable, with only about 6 % loss over 20 000 cycles. 相似文献
18.
A tin oxide-titanium oxide/graphene (SnO2-TiO2/G) ternary nanocomposite as high-performance anode for Li-ion batteries was prepared via a simple reflux method. The graphite oxide (GO) was reduced to graphene nanosheet, and the SnO2-TiO2 nanocomposites were evenly distributed on the graphene matrix in the SnO2-TiO2/G nanocomposite. The as-prepared SnO2-TiO2/G nanocomposites were employed as anode materials for lithium-ion batteries, showing an outstanding performance with high reversible capacity and long cycle life. The composite delivered a superior initial discharge capacity of 1,594.6 mAh g?1 and a reversible specific capacity of 1,500.3 mAh g?1 at a current density of 100 mA g?1. After 100 cycles, the reversible discharge capacity was still maintained at 1,177.4 mAh g?1 at a current density of 100 mA g?1 with a high retained rate of reversible capacity of 73.8 %. The addition of small amount of TiO2 nanoparticles improved the cycling stability and specific capacity of SnO2-TiO2/G nanocomposite, obviously. The results demonstrate that the SnO2-TiO2/G nanocomposite is a promising alternative anode material for practical Li-ion batteries. 相似文献
19.
We report a convenient, low-cost and ecofriendly approach for the fabrication of a Co3O4/CoOOH electrode material intended for lithium ion batteries (LIBs) and supercapacitors (SCs) using the electrochemical dispersion of the cobalt foil through the pulse alternating current (PAC) method. The synthesized material is a Co3O4/CoOOH composite (with about 10–15 wt% CoOOH) in the form of nanosheets with a length of approximately 200 nm and a thickness of 10–20 nm. It is found to exhibit high reversible discharge specific capacities and good cycling behavior while tested as the anode material in LIBs. Measuring the reversible capacitance at high (2C) and low (C/20) cycling rates gives the values of 610 mAh g−1 and 1030 mAh g−1, respectively. The specimen possesses excellent performance as the electrode for SCs with the retention of capacitance up to 98% at the current density increasing from 0.5 to 10 A g−1. After 1000 cycles at a current density of 10 A g−1 the electrode maintains about 90% of its initial capacitance which evidences the long cycle life. Hence, electrochemically prepared Co3O4/CoOOH seems to be a promising candidate for high-performance LIBs and SCs applications. 相似文献
20.
Dr. Chunxiu Hua Dr. Xiangpeng Fang Prof. Zhaoxiang Wang Prof. Liquan Chen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(18):5487-5491
It is well accepted that metallic tin as a discharge (reduction) product of SnOx cannot be electrochemically oxidized below 3.00 V versus Li+/Li0 due to the high stability of Li2O, though a similar oxidation can usually occur for a transition metal formed from the corresponding oxide. In this work, nanosized Ni2SnO4 and NiO/SnO2 nanocomposite were synthesized by coprecipitation reactions and subsequent heat treatment. Owing to the catalytic effect of nanosized metallic nickel, metallic tin can be electrochemically oxidized to SnO2 below 3.00 V. As a result, the reversible lithium‐storage capacities of the nanocomposite reach 970 mAh g?1 or above, much higher than the theoretical capacity (ca. 750 mAh g?1) of SnO2, NiO, or their composites. These findings extend the well‐known electrochemical conversion reaction to non‐transition‐metal compounds and may have important applications, for example, in constructing high‐capacity electrode materials and efficient catalysts. 相似文献