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1.
《Ceramics International》2016,42(14):15464-15470
The TiN coated Li4Ti5O12 (LTO) submicrospheres with high electrochemical performance as anode materials for lithium-ion battery were synthesized successfully by solvothermal method and subsequent nitridation process in the presence of ammonia. The XRD results revealed that the crystal structure of LTO did not change after thermal nitridation process. The submicrospheres morphology of LTO and TiN film on the surface of LTO submicrospheres were characterized by FESEM and HRTEM, respectively. XPS result confirmed that a small amount of Ti changed from Ti4+ to Ti3+ after nitridation process, which will increase the electronic conductivity of LTO. Electrochemical results showed that electrochemical performance of TiN coated LTO anode materials compared favorably with that of pure LTO. Also its rate capability and cycling performance were apparently superior to those of pure LTO. The reversible capacity of TiN-LTO is 105.2 mA h g−1 at a current density of 10 C after 100 cycles and maintain 92.9% of its initial discharge capacity, while that of pure LTO is only 83.6 mA h g−1 with a capacity retention of 90.3%. Even at 20 C, the discharge capacity of TiN coated LTO sample is 101.3 mA h g−1, compared with 77.3 mA h g−1 for pristine LTO in the potential range 1.0–2.5 V (vs. Li/Li+). 相似文献
2.
《Ceramics International》2017,43(8):6232-6238
Uniform Nb2O5 nanospheres/surface-modified graphene (SMG) composites for anode materials in lithium ion batteries were synthesized by hydrothermal method. The microstructure and morphology of composites were investigated by X-ray diffraction, scanning electron microscopy and transmission electron microscope techniques. The experimental results showed that Nb2O5 nanospheres were tightly and uniformly grown on the surface of SMG nanosheets. Nb2O5 nanospheres/SMG composites exhibited an impressive reversible capacity of 404.6 mA h g−1 at the current density of 40 mA g−1 after 100 cycles, and an excellent rate capacity of 345.5 mA h g−1 at the current density of 400 mA g−1. 相似文献
3.
《Ceramics International》2017,43(13):9630-9635
Transition metal sulfides have been proved as promising candidates of anode materials for sodium-ion batteries (SIBs) due to their high sodium storage capacity, low cost and enhanced safety. In this study, the amorphous CoS nanoparticle/reduced graphene oxide (CoS/rGO) composite has been fabricated by a facile one-step electron beam radiation route to in situ decorate amorphous CoS nanoparticle on the rGO nanosheets. Benefiting from the small particle size (~2 nm), amorphous structure, and electronic conductive rGO nanosheets, the CoS/rGO nanocomposite exhibits high sodium storage capacity (440 mAh g−1 at 100 mA g−1), excellent cycling stability (277 mAh g−1 after 100 cycles at 200 mA g−1, 79.6% capacity retention) and high rate capability (149.5 mAh g−1 at 2 A g−1). The results provide a facile approach to fabricate promising amorphous and ultrafine metal sulfides for energy storage. 相似文献
4.
《Carbon》2014
A composite of graphene oxide sheets, carbon nanotubes (CNTs), and commercial graphite particles was prepared. The composite’s use as a high-capacity and binder-free anode material for Li-ion batteries was examined. Results showed that this novel composite had a very high reversible Li-storage capacity of 1172.5 mA h g−1 at 0.5C (1C = 372 mA g−1), which is thrice that of commercial graphite anode. The composite also exceeded the theoretical sum of capacities of the three ingredients. More importantly, its reversible capacity below 0.25 V can reach up to 600 mA h g−1. In summary, the graphene oxide/graphite/CNT composite had higher reversible capacity, better cycling performance, and similar rate capability compared with the graphene oxide/graphite composite. 相似文献
5.
《Carbon》2013
Reduced graphene oxide (rGO) tethered with maghemite (γ-Fe2O3) was synthesized using a novel modified sol–gel process, where sodium dodecylbenzenesulfonate was introduced into the suspension to prevent the undesirable formation of an iron oxide 3D network. Thus, nearly monodispersed and homogeneously distributed γ-Fe2O3 magnetic nanoparticles could be obtained on surface of graphene sheets. The utilized thermal treatment process did not require a reducing agent for reduction of graphene oxide. The morphology and structure of the composites were investigated using various characterization techniques. As-prepared rGO/Fe2O3 composites were utilized as anodes for half lithium ion cells. The 40 wt.%-rGO/Fe2O3 composite exhibited high reversible capacity of 690 mA h g−1 at current density of 500 mA g−1 and good stability for over 100 cycles, in contrast with that of the pure-Fe2O3 nanoparticles which demonstrated rapid degradation to 224 mA h g−1 after 50 cycles. Furthermore, the composite showed good rate capability of 280 mA h g−1 at 10C (∼10,000 mA g−1). These characteristics could be mainly attributed to both the use of an effective binder, poly(acrylic acid) (PAA), and the specific hybrid structures that prevent agglomeration of nanoparticles and provide buffering spaces needed for volume changes of nanoparticles during insertion/extraction of Li ions. 相似文献
6.
Evaluation of reduced graphene oxide-supported NiSb2O6 nanocomposites for reversible lithium storage
《Ceramics International》2016,42(13):14782-14787
NiSb2O6 and reduced graphene oxide (NiSb2O6/rGO) nanocomposites are successfully fabricated by a solid-state method combined with a subsequent solvothermal treatment and further used as anode material of lithium-ion battery. The NiSb2O6/rGO nanocomposites exhibit a higher reversible capacity (of ca. 1240.5 mA h g−1 at a current density of 50 mA g−1), along with a good rate capability (395.2 mA h g−1 at a current density of 1200 mA g−1) and excellent capacity retention (684.5 mA h g−1 after 150 cycles). These good performances could be attributed to the incorporated reduced grapheme oxide, which significantly improves the electronic conductivity of the NiSb2O6. 相似文献
7.
《Ceramics International》2015,41(6):7556-7564
In this work, three-dimensional hierarchical ZnCo2O4 flower-like microspheres have been synthesized on a large scale via a facile and economical citrate-mediated hydrothermal method followed by an annealing process in air. The as-synthesized ZnCo2O4 flower-like microspheres are constructed by numerous interweaving porous nanosheets. According to the experimental results, a formation mechanism involving the assembly of the nanosheets from nanoparticles into flower-like microsphere is proposed. As a virtue of their beneficial structural features, the ZnCo2O4 flower-like microspheres exhibit a high lithium storage capacity and excellent cycling stability (1136 mA h g−1 at 100 mA g−1 after 50 cycles). This remarkable electrochemical performance can be ascribed to the hierarchical structure and porous structures in the nanosheets, which effectively increases the contact area between the active materials and the electrolyte, shortening the Li+ diffusion pathway and buffering the volume variation during cycling. 相似文献
8.
Chaofeng Zhang Xing Peng Zaiping Guo Chuanbin Cai Zhixin Chen David Wexler Sean Li Huakun Liu 《Carbon》2012,50(5):1897-1903
A simple approach is reported to prepare carbon-coated SnO2 nanoparticle–graphene nanosheets (Gr–SnO2–C) as an anode material for lithium ion batteries. The material exhibits excellent electrochemical performance with high capacity and good cycling stability (757 mA h g?1 after 150 cycles at 200 mA g?1). The likely contributing factors to the outstanding charge/discharge performance of Gr–SnO2–C could be related to the synergism between the excellent conductivity and large area of graphene, the nanosized particles of SnO2, and the effects of the coating layer of carbon, which could alleviate the effects of volume changes, keep the structure stable, and increase the conductivity. This work suggests a strategy to prepare carbon-coated graphene–metal oxide which could be used to improve the electrochemical performance of lithium ion batteries. 相似文献
9.
SnO2 nano-spheres/graphene composite was fabricated via a simple one-step hydrothermal method with graphene oxide and SnCl4·5H2O as the precursors. The composite was characterized by X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy and surface area measurement. It is shown that fine SnO2 nano-spheres with an average size of 50–100 nm could be homogeneously deposited on graphene nano-sheets layer by layer. The structural feature enabled SnO2 nano-spheres/graphene hybird as an excellent anode material in lithium ion battery. The composite possesses 1306 mA h g?1 of initial discharge capacity and good capacity retention of 594 mA h g?1 up to the 50th cycle at a current density of 100 mA g?1. These results indicate that the composite is a promising anode material in high-performance lithium ion batteries. 相似文献
10.
《Ceramics International》2017,43(15):11556-11562
The ternary composite, carbon coated hollow ZnSnO3 (ZS@C) cubes encapsulated in reduced graphene oxide sheets (ZS@C/rGO), was synthesized via low-temperature coprecipitation and colloid electrostatic self-assembly. The uniform carbon-coating layer not only plays a role in buffering the volume change of ZnSnO3 cubes in the charging/discharging processes, but also forms three-dimensional network with the cooperation of graphene to maintain the structural integrity and improve the electrical conductivity. The results show that the reduced graphene oxide sheets encapsulated ZS@C microcubes with a typical core-shell structure of ~700 nm in size exhibit an improved electrochemical performance compared with bare ZS@C microcubes. The ZS@C/rGO electrode delivered an initial discharge capacity of 1984 mA h g−1 at a current density of 0.1 A g−1 and maintained a capacity of 1040 mA h g−1 after 45 cycles. High specific capacity and superior cycle stability indicate that the ZS@C/rGO composite has a great potential for the application of lithium-ion anode material. 相似文献
11.
《Ceramics International》2017,43(2):2136-2142
ZnFe2O4-graphene composite nanofibers were prepared through electrospinning technique, then with graphene oxide by the facile solvothermal method to get the final products for the first time. The obtained ZnFe2O4 nanofibers composed of numerous same size nanoparticles wrapped by graphene sheets to form a unique nanostructure. When the ZnFe2O4-graphene electrode was evaluated as anode for lithium-ion batteries, good rate capability and long-term cycling stability could be achieved. The ZnFe2O4-graphene electrode exhibited a first discharge capacity of 2166 mAh g−1 cycling at 0.05 C, remained an average reversible capacity of 1000 mAh g−1 after 50 cycles, and kept the high rate capacities of 899, 822, 760 and 711 mAh g−1 at the current rates of 0.5, 1, 2 and 5 C, respectively. The excellent electrochemical performance could be ascribed to the following reasons: the large electrochemical active surface area provided by the composite nanofibers; the graphene sheets decreased the internal resistance of the lithium-ion batteries, which resulted from the electrical conductivity of the graphene sheets; the graphene sheets as conductive network could effectively restrain the agglomeration of ZnFe2O4 nanopaiticals. 相似文献
12.
《Carbon》2015
A unique polymerized C60 thin film was functionalized by radio frequency – plasma-assisted thermal evaporation as a passivation layer for the fluorine-doped tin oxide (SnO2:F) anode of a lithium-ion battery. The plasma-polymerized C60 coated SnO2:F anode exhibited a high initial discharge capacity of 1255 mAh g−1 at 0.15 mA cm−2 and increased coulombic efficiency of 98%. These electrochemical improvements were due to the polymerized C60 coating layer, which enhanced the transport of lithium ions on the surface of the active material and mechanically stabilized the anode material during electrochemical cycling. 相似文献
13.
《Ceramics International》2016,42(15):16956-16960
In this article, V2O5 with a novel nest-like hierarchical porous structure has been synthesized by a facile solvothermal method and investigated as cathode material for lithium-ion batteries. The nest-like V2O5 with a diameter of about 1.5 µm, was composed of interconnected nanosheets with a highly porous structure. Without other modification, the as-prepared V2O5 electrode exhibited superior capacity. An initial discharge capacity of 330 mAh g−1 (at a current density of 100 mA g−1) could be delivered and a stable discharge capacity of 240 mAh g−1 after 50 cycles is maintained. The excellent performance was attributed to the hierarchical porous structure that could buffer against the local volume change and shorten the lithium-ions diffusion distance. 相似文献
14.
《Carbon》2013
A simple approach was developed for the fabrication of a Fe2O3/carbon composite by impregnating activated carbon with a ferric nitrate solution and calcinating it. The composite contains graphitic layers and 10 wt.% Fe2O3 particles of 20–50 nm in diameter. The composite has a high specific surface area of ∼828 m2 g−1 and when used as the anode in a lithium ion battery (LIB), it showed a reversible capacity of 623 mAh g−1 for the first 100 cycles at 50 mA g−1. A discharge capacity higher than 450 mAh g−1 at 1000 mA g−1 was recorded in rate performance testing. This highly improved reversible capacity and rate performance is attributed to the combination of (i) the formation of graphitic layers in the composite, which possibly improves the matrix electrical conductivity, (ii) the interconnected porous channels whose diameters ranges from the macro- to meso- pore, which increases lithium-ion mobility, and (iii) the Fe2O3 nanoparticles that facilitate the transport of electrons and shorten the distance for Li+ diffusion. This study provides a cost-effective, highly efficient means to fabricate materials which combine conducting carbon with nanoparticles of metal or metal oxide for the development of a high-performance LIB. 相似文献
15.
《Ceramics International》2015,41(8):9655-9661
The hollow core–shell ZnMn2O4 microspheres are successfully prepared by a solvothermal carbon templating method and then a annealing process. The crystal phase and particle morphology of resultant ZnMn2O4 microspheres are characterized by XRD and TEM. The electrochemical properties of the ZnMn2O4 microspheres as an anode material are investigated for lithium ion batteries. The results show that the ZnMn2O4 microspheres exhibit a reversible capacity of 855.8 mA h g−1 at a current density of 200 mA g−1 after 50 cycles. Even at 1000 mA g−1, the reversible capacity of the ZnMn2O4 microspheres is still kept at 724.4 mA h g−1 after 60 cycles. The enhanced electrochemical performance suggests the promising potential of the hollow core–shell ZnMn2O4 microspheres in lithium-ion batteries. 相似文献
16.
《Ceramics International》2017,43(15):11967-11972
Stabilizing the layer structures of Mo-based anode materials is still a challenge for Li ion batteries. Herein, we proposed an electrochemical presodiation strategy for MoS2 and MoO3 to improve their cycling stability. It is interesting to note that the cycling stability of as-treated MoS2 and MoO3 was significantly improved. Although the reversible discharge capacity was slightly decreased, the capacity of the pretreated MoS2 at 300 mA g−1 was retained at 345 mA h g−1 after 100 cycles while that of the pristine one decreased to 151 mA h g−1. The capacity of the pretreated MoO3 after 60 cycles was also improved from 275 mA h g−1 (the pristine one) to 460 mA h g−1. The stabilizing effect was further verified by scanning electron microscope (SEM) analysis. Electrochemical presodiation here could be a promising modification strategy for Mo-based anode materials. 相似文献
17.
Simple self-assembly of SnS2 entrapped graphene aerogel and its enhanced lithium storage performance
《Ceramics International》2016,42(6):6572-6580
In this work, SnS2 nanoplates entrapped graphene aerogel has been successfully prepared by simple self-assembly of reduced graphene oxide obtained through mild chemical reduction. Structural and morphological investigations demonstrated that SnS2 nanoplates are highly dispersed in the three dimensional (3D) porous graphene matrix. When served as anode material for lithium-ion batteries, the electrochemical properties of SnS2/graphene aerogel (SnS2/GA) were evaluated by galvanostatic discharge–charge tests, cyclic voltammetry and impedance spectroscopy measurement. Compared with pristine SnS2, the SnS2/GA nanocomposite achieved a much higher initial reversible capacity (1186 mAh g−1), superior cyclic stability (1004 mAh g−1 after 60 cycles, corresponding to 84.7% of the initial reversible capacity), as well as better rate capability (650 mAh g−1 at a current density of 1000 mA g−1). This significantly improved lithium storage performance can be attributed to the good integration of SnS2 nanoplates with 3D porous graphene network, which can not only provide much more active sites and easy access for Li ions intercalation, but also prevent the aggregation of SnS2 nanoplates and facilitate fast transportation of Li ions and surface electrons during the electrochemical process. 相似文献
18.
《Ceramics International》2017,43(12):8590-8595
To improve the electrochemical performance of silicon-based anode material, lithium fluoride (LiF) and pitch carbon were introduced to co-modify a silicon/graphite composite (SG), in which the graphite acts as a dispersion matrix. The pitch carbon helps to improve the electronic conductivity and lithium ion transport of the material. LiF is one of the main components of the solid electrolyte interphase (SEI) formed on the silicon surface, helping to tolerate the large volume changes of Si during lithiation/delithiation. The modified SG sample delivered a capacity of over 500 mA h g−1, whereas unmodified SG delivered a capacity of lower than 50 mAh g−1 after 100 cycles at 100 mA g−1. When performed at 4 A g−1, the reversible capacity of the modified SG was 346 mAh g−1, much higher than that of SG (only 37 mA h g−1). The enhanced cycling and rate properties of the modified SG can be attributed to the synergetic contribution of the pitch carbon and LiF which help accommodate the volume change, reduce the side reaction, and form a stable solid electrolyte interface layer. 相似文献
19.
《Ceramics International》2017,43(3):3218-3223
In this work, the nanosized porous MnCo2O4 microspheres were synthesized by a hydrothermal method and their electrochemical behaviors were investigated based on a carbon supported composite air electrode for rechargeable sodium-air batteries. Under dry air test condition, the MnCo2O4/C air electrode demonstrated a stable working voltage of around 2.1 V vs. Na+/Na and a high initial discharge capacity of 7709.4 mA h g−1, based on the active material mass, at a current density of 0.1 mA cm−2. By a limit on the depth of discharge, the cell exhibited a specific capacity of 1000 mA h g−1 with a high cycling stability up to 130 cycles. The considerable electrocatalytic activity suggests that the as-proposed MnCo2O4 is a highly efficient catalyst as air electrode for rechargeable sodium-air batteries. 相似文献
20.
《Ceramics International》2016,42(16):18568-18572
A novel MnO@Amorphous C-Carbon nanotubes (MnO@C-CNTs) composite is prepared by chemical vapor deposition (CVD). When used as an anode material for Li-ion batteries, the MnO@C-CNTs composite exhibits an initial discharge capacity of 1164 mA h g−1 at 100 mA g−1 and the discharge capacity gradually increased from 571.7 mA h g−1 to 654 mA h g−1 after 100 cycles at 1 A g−1, which shows an increase of the capacity rather than attenuation. Furthermore, the MnO@C-CNTs electrode can deliver a capacity of up to 228 mA h g−1 at 5 A g−1. These results indicate that the three-dimensional conductive network of the MnO@C-CNTs composite could prevent the aggregation of MnO particles, and its open structure allows electrolyte penetration, and reduces the diffusion path of the lithium ions, hence maximizes utilization of the electrochemically active MnO particles, while enhances the conductivity of electrode material and Li+ transport. This work offers a universal approach to design various metal oxides@C-CNTs composite. 相似文献