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1.
The hollow graphene oxide spheres have been successfully fabricated from graphene oxide nanosheets utilizing a water-in-oil emulsion technique, which were prepared from natural flake graphite by oxidation and ultrasonic treatment. The hollow graphene oxide spheres were reduced to hollow graphene spheres at 500°C for 3 h under an atmosphere of Ar(95%)/H2(5%). The first reversible specific capacity of the hollow graphene spheres was as high as 903 mAh g-1 at a current density of 50 mAh g-1. Even at a high current density of 500 mAh g-1, the reversible specific capacity remained at 502 mAh g-1. After 60 cycles, the reversible capacity was still kept at 652 mAh g-1 at the current density of 50 mAh g-1. These results indicate that the prepared hollow graphene spheres possess excellent electrochemical performances for lithium storage. The high rate performance of hollow graphene spheres thanks to the hollow structure, thin and porous shells consisting of graphene sheets.
PACS
81.05.ue; 61.48.Gh; 72.80.Vp 相似文献2.
As a metal oxide with a high theoretical capacity, SnO2 is considered to be one of the promising alternative anode materials in lithium-ion batteries. However, the pulverization of electrodes caused by the large volume expansion of SnO2 during repeated charge/discharge hinders its practical application. Here, SnO2 nanoparticles decorated on a 3D carbon network structure formed by the interconnection of graphene and CNT (SnO2/G + CNT), which is designed and successfully synthesized via in situ chemical synthesis and thermal treatment. In this structure, the SnO2 with nanosized can increase energy storage points and decrease the ions transport length, the carbon network can build a high conductive network that facilitates electron transport and alleviate the volume expansion to prevent electrode pulverization. In addition, graphene has a high specific surface area effect that facilitates lithium-ion storage, and the CNT also supports the graphene frame to make the carbon skeleton structure more stable, and provides a large number of ion transport channels, increasing the active sites of the reaction. Due to this excellent structure with synergistic effects, the SnO2/G + CNT electrode exhibits superior reversible capacity (1227.2 mAh g-1 at 0.1 A g-1 after 200 cycles), superior rate capacity (549.3 mAh g-1 at 3.0 A g-1) and long cycle stability (1630.1 mAh g-1 at 0.5 A g-1 after 1000 cycles). 相似文献
3.
Yun Zhao Qidong Lin Yong Li Canliang Ma 《International Journal of Applied Ceramic Technology》2019,16(1):304-314
An unique ordered mesoporous network consisting of carbon-coated SnO2 nanoparticles (NPs) is developed by a facile self-assemble strategy via a solvethermal route in which employs N,N-dimethylformamide/H2O as mixture solvent and polyvinyl pyrrolidone as barrier agent and carbon source. The SnO2-NPs with an uniform dimension of ~5 nm are observed to interconnect with each other, and assemble into high-compact blocks where abundant mesopores with an average diameter of ~4 nm are found throughout the body. The carbon coating with a thickness of <1 nm are confirmed to exist on these SnO2-NPs, which is of great importance to avoid the severe sintering that occurs in the case of bare SnO2-NPs. Furthermore, the carbon coating plays roles in enhancing conductivity and keeping the active particles from being directly contacted with electrolyte, and thus contributes to enhanced reversible capacity of 949 mAh g−1 and improved initial Coulombic efficiency. The composite electrode with a high tap density of 2.0 g cm−3 exhibits substantially elevated electrochemical performances, such as a charge capacity of 565 mAh g−1 vs 223 mAh g−1 of common SnO2-NPs after 60 cycles and greatly improved rate capability, indicating the promising applications of this advanced micro-nano architecture for next-generation lithium-ion batteries. 相似文献
4.
The reasonable structure construction of electrode materials with superior performance is desired for the new generation lithium ion batteries (LIBs). Herein, binder-free multilayered SnO2/graphene (GN) on Ni foam was fabricated via a dip coating method. SnO2 nanoparticles and GN were alternatively coated on Ni foam to form a sandwich-like structure. The wrapping of GN can raise the conductivity and keep the structural integrality of the binder-free material, preventing structure collapse arised from the volume expansion of SnO2. Benefiting from the porous Ni foam framework and sandwich-like structure, the SnO2/GN composite exhibited good rate performance and excellent cycle stability. High capacities of 708 and 609?mAh?g?1 were achieved at rates of 1 and 2?A?g?1. Besides, the SnO2/GN electrode delivered a high capacity of 757?mAh?g?1 after 500 cycles at 1?A?g?1. 相似文献
5.
Robin Von Hagen Mahima Sneha Sanjay Mathur 《Journal of the American Ceramic Society》2014,97(4):1035-1040
Hollow tin‐oxide (SnO2) nanospheres were synthesized by coating, carbon nanospheres (CNs) as hard templates, with a tin(IV) sol obtained by partial hydrolysis of [Sn(OBut)4] under ambient conditions. Formation of crystalline SnO2 spheres upon calcination was confirmed by powder X‐ray diffraction data, whereas the hollow interiors of SnO2 particles were verified by scanning and transmission electron microscopy of both intact and broken spheres. The shell of SnO2 nanospheres sintered at 700°C consisted of a single layer of nanocrystallites (~6 nm) self‐assembled in a ball‐like superlattice. Tin‐oxide hollow spheres showed an average diameter of 150 nm and could be homogeneously dispersed in water/ethylene glycol (50:50 vol%) mixture to form stable inorganic inks viable for their use in commercial ink‐jet printers demonstrated by printing porous ceramic structures on an interdigitated sensor chip. The integration of large surface and nanoscopic voids in the final structures imparted higher sensitivity to the as‐printed sensors toward both oxidizing (nitrogen dioxide) and reducing gases (methane and ethanol), which validates the enormous potential of printable inorganics in functional applications. 相似文献
6.
《Ceramics International》2022,48(13):18625-18634
Many advantages made SnO2 a potential anode for lithium-ion batteries, but huge volume expansion during cycling seriously impeded its practical application. Here, a novel double-carbon structure with low graphene weight proportion was successfully prepared using a facile hydrothermal method to enhance the long-cycle stability of SnO2 as anodes for lithium-ion batteries. In this structure, SnO2 nanoparticles were formed around the surface of the carbon microspheres (CMS), and the reduced graphene (GR) shuttled through the outer layer. As anodes for lithium-ion batteries, the SnO2 protected by dual carbon (CMS@SnO2/GR) exhibited outstanding cycle performance with an initial reversible capacity of 789.5 mAh g-1 and the reversible capacity retention rate of 68.6% after 350 cycles at 200 mA g-1. The abundance free space among CMS, nano-scale, and the excellent flexibility of graphene were all contributed to alleviating the volume variation of CMS@SnO2/GR during the lithiation and delithiation. 相似文献
7.
Peichao Lian Xuefeng Zhu Shuzhao Liang Zhong Li Weishen Yang Haihui Wang 《Electrochimica acta》2011,(12):395
A gas–liquid interfacial synthesis approach has been developed to prepare SnO2/graphene nanocomposite. The as-prepared nanocomposite was characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and Brunauer–Emmett–Teller measurements. Field emission scanning electron microscopy and transmission electron microscopy observation revealed the homogeneous distribution of SnO2 nanoparticles (2–6 nm in size) on graphene matrix. The electrochemical performances were evaluated by using coin-type cells versus metallic lithium. The SnO2/graphene nanocomposite prepared by the gas–liquid interface reaction exhibits a high reversible specific capacity of 1304 mAh g−1 at a current density of 100 mA g−1 and excellent rate capability, even at a high current density of 1000 mA g−1, the reversible capacity was still as high as 748 mAh g−1. The electrochemical test results show that the SnO2/graphene nanocomposite prepared by the gas–liquid interfacial synthesis approach is a promising anode material for lithium-ion batteries. 相似文献
8.
《Ceramics International》2019,45(10):13219-13224
Hollow graphene spheres are successfully prepared and employed as the separator coating materials for lithium-sulfur batteries. The hollow graphene spheres coated separator has been proven an efficient trap to adsorb and block polysulfide, greatly alleviating the shuttle effect. In the case of using elemental sulfur as cathode active material and the weight of the diaphragm is only increased by 10.3%, the lithium-sulfur battery with hollow graphene spheres coated separator delivers a high initial specific capacity of 1172.3 mAh g−1 at the current density of 0.2 C, and the discharge capacity remains at 829.6 mAh g−1 after 200 cycles with a capacity decay of 0.146% per cycle, showing excellent electrochemical performance. 相似文献
9.
SnO2–graphene–carbon nanotube (SnO2–G–CNT) mixture is synthesized using graphene oxide as precursor for application as anode material in rechargeable Li ion batteries. It is shown that the SnO2 nanoparticles of 3–6 nm in diameter are not only attached onto the surface of graphene sheets by anchoring with surface functional groups, but they also are encapsulated in pore channels formed by entangled graphene sheets. The incorporation of carbon nanotubes reduces the charge transfer resistance of the anode made from the mixture through the formation of 3D electronic conductive networks. The SnO2–G–CNT anodes deliver remarkable capacities of 345 and 635 mAh g−1 at 1.5 and 0.25 A g−1, respectively. Flexible electrodes consisting of highly-aligned SnO2–G–CNT papers are also prepared using a simple vacuum filtration technique. They present a stable capacity of 387 mAh g−1 at 0.1 A g−1 after 50 cycles through the synergy of the high specific capacity of SnO2 nanoparticles and the excellent cycleability of G–CNT paper. 相似文献
10.
SnO2 nanoparticles were dispersed on graphene nanosheets through a solvothermal approach using ethylene glycol as the solvent. The uniform distribution of SnO2 nanoparticles on graphene nanosheets has been confirmed by scanning electron microscopy and transmission electron microscopy. The particle size of SnO2 was determined to be around 5 nm. The as-synthesized SnO2/graphene nanocomposite exhibited an enhanced electrochemical performance in lithium-ion batteries, compared with bare graphene nanosheets and bare SnO2 nanoparticles. The SnO2/graphene nanocomposite electrode delivered a reversible lithium storage capacity of 830 mAh g−1 and a stable cyclability up to 100 cycles. The excellent electrochemical properties of this graphene-supported nanocomposite could be attributed to the insertion of nanoparticles between graphene nanolayers and the optimized nanoparticles distribution on graphene nanosheets. 相似文献
11.
TiO2/SnO2 double-shelled hollow spheres are successfully synthesized by two-step liquid-phase deposition method using carbon sphere templates. The formation process of TiO2/SnO2 hollow spheres is discussed. The samples are characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy and UV–vis absorption spectroscopy. The behavior of photogenerated charges in the TiO2/SnO2 heterojunction structures has been investigated through surface photovoltage spectroscopy. The TiO2/SnO2 hollow spheres which are realized show significantly enhanced photocatalytic activities, with respect to the cases of SnO2 and TiO2 hollow spheres. Furthermore, TiO2/SnO2 hollow spheres show good recyclable photocatalytic activities. 相似文献
12.
Xiaoming Yin Libao Chen Chengchao Li Quanyi Hao Shuang Liu Qiuhong Li Endi Zhang Taihong Wang 《Electrochimica acta》2011,(5):3646
This paper firstly reported a simple route to prepare SnO2 mesoporous spheres for lithium ion battery. Mesoporous SnO2 spheres in range of 100–300 nm were prepared by primary reaction at 353 K for 30 min, and calcination process at 773 K, which could be scaled up for manufacturing. The nano-size effect of the small particle and the 3D mesoporous structure promoted the electrolyte and lithium ion transfer and suppressed the volume changes, which greatly enhanced the cycle performances. As the anode material, it could deliver 761 mAh g−1 capacity after 50 cycles at the current density of 200 mA g−1. Even at 2 A g−1, it retained 480 mAh g−1 after 50 cycles. Furthermore, we suggested that the high stability of the structure was responsible for the improved cycle properties. 相似文献
13.
Bing Zhao Guohua Zhang Jinsong Song Yong Jiang Hua Zhuang Peng Liu Tao Fang 《Electrochimica acta》2011,(21):423
Co-precipitation method of SnCl2·2H2O and graphene oxide (GO) solution was performed to fleetly prepare graphene/SnO2 composite. The structure and composition of the nanocomposite were detected by means of XRD, SEM, TEM and FT-IR. The GO was reduced by bivalent tin ions to graphene nanosheet (GNS) via solution reaction and SnO2 nano-crystals with size of 4–6 nm were homogeneously distributed on the matrix of GNS. It was found that the disorder degree of graphene in GNS/SnO2 composite prepared by the bivalent tin ion assisted reduction method was much lower than that of GNS obtained via pyrolysis reduction. The possible mechanism for this phenomenon was discussed in detail. The N2 adsorption tests showed an ink-bottle-like pore structure of GNS/SnO2 and the SnO2 nanoparticles were confined in the interlayer of GNS without agglomeration. These structural features were desirable and enabled GNS/SnO2 an excellent anode material in lithium ion battery. The electrochemical tests showed that the composite could deliver a reversible capacity of 775.3 mAh/g and capacity retention of 98% after 50 cycles. 相似文献
14.
Sang-Chai Kim Young-Kwon Park Byung Hoon Kim Hangun Kim Won-June Lee Heon Lee Sang-Chul Jung 《Korean Journal of Chemical Engineering》2018,35(3):750-756
A high-performance lithium ion battery (LIB) electrode was prepared by precipitating tin oxide nanoparticles on graphene powder by the liquid phase plasma (LPP) method. The particles generated by the LPP reaction are spherical SnO2 nanoparticles with a size of 5-10 nm, as confirmed by a variety of analytical devices. The quantity of SnO2 nanoparticles partially aggregated on the graphene sheet surface increases as the initial concentration of the tin precursor increases. The SnO2/graphene nanocomposites (SGNC) electrodes prepared by the LPP method demonstrated improved cycling stability and reversible lithium storage capacity as compared to the bare graphene electrode. The precipitated tin oxide improves the lithium storage capacity, but excess tin oxide nanoparticles rather reduced the cycling stability. 相似文献
15.
《Carbon》2015
A porous tin peroxide/carbon (SnO2/C) composite electrode coated with an amorphous carbon layer is prepared using a facile method. In this electrode, spherical graphite particles act as supporter of electrode framework, and the interspace among particles is filled with porous amorphous carbon derived from decomposition of polyvinylidene fluoride and polyacrylonitrile. SnO2 nanoparticles are uniformly embedded in the porous amorphous carbon matrix. The pores in amorphous carbon matrix are able to buffer the huge volume expansion of SnO2 during charge/discharge cycling, and the carbon framework can prevent the SnO2 particles from pulverization and re-aggregation. The carbon coating layer on the outermost surface of electrode can further prevent porous SnO2/C electrode from contacting with electrolyte directly. As a result, the repeated formation of solid electrolyte interface is avoided and the cycling stability of electrode is improved. The obtained SnO2/C electrode presents an initial coulombic efficiency of 77.3% and a reversible capacity of 742 mA h g−1 after 130 cycles at a current density of 100 mA g−1. Furthermore, a reversible capacity of 679 mA h g−1 is obtained at 1 A g−1. 相似文献
16.
《Ceramics International》2019,45(15):18743-18750
Due to their ultra-high theoretical capacity and low discharge potential, rich Sn-based materials are considered promising candidates for lithium ion battery (LIB) anodes; however, the development of SnOx electrodes is restricted by their low conductivity and severe volume change during repeated cycling. In this study, carbon matrix encapsulating heterostructured SnOx ultrafine nanoparticles (SnOx@C/rGO) were synthesized in situ through a facile solvent mixing, followed by thermal calcination. During the decomposition of the Sn-organic precursor, the sizes of the as-prepared SnOx nanoparticles were strictly controlled to 5–10 nm; they were intimately wrapped by the in-situ formation of ultrathin carbon layers, which prevented the agglomeration of nanograins. Furthermore, the SnOx@C nanoparticles were evenly anchored on the surface of reduced graphene oxide (rGO) to construct a highly conductive carbon framework. It is notable that the carbon matrix prepared in situ can accommodate the volumetric change of SnOx and facilitate the transport of Li+ ions during continuous cycling. Benefiting from the synergistic effect between the SnOx nanoparticles and carbon matrix prepared in situ, the heterostructured SnOx@C/rGO will confer improved structural stability and reaction kinetics for lithium storage. It delivers a stable reversible discharge capacity of 1092.2 mAh g−1 at a current rate of 0.1 A g−1, and enhanced cycling retention with a capacity of 447.8 mAh g−1 after 1200 cycles at a current rate of 5.0 A g−1. This strategy provides a rational avenue to design oxide anodes with efficient hierarchical structure for LIB development. 相似文献
17.
Jian Wei Bing Chen Huan Su Xueting Li Chao Jiang Shishuai Qiao Hao Zhang 《Ceramics International》2021,47(8):10965-10971
Lithium-sulfur(Li–S)batteries have received extensive attention due to the high theoretical energy density. However, tremendous works have been made to improve the three major problems of Li–S batteries. Namely, electrical insulation of sulfur, shuttle effect of polysulfide, and volume expansion of sulfur. However, there are still huge challenges to solve these problems and improve capacity. Here, we propose a strategy to prepare a double-shelled structure S@V2O5 spheres @GO composite.The polar hollow V2O5 sphere can realize the chemical adsorption of polysulfides and graphene oxide facilitates good electronic conductivity, thereby improving rate capability and cycling performance. The cycle capacity of S@V2O5 spheres @GO composite remains 895.7 mAh/g at 0.1C after 100 cycles and low capacity decay of 0.015% after 200 cycles at 1C rate, attributed to the double-shelled structure of the S@V2O5 spheres @ GO, the resulting electrode exhibits better performance. Offering a potential candidate for practical application of Li–S batteries in the future. 相似文献
18.
SnO2-coated multiwall carbon nanotube (MWCNT) nanocomposites were synthesized by a facile hydrothermal method. The as-prepared nanocomposites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA). The SnO2/MWCNT composites, when combined with carboxymethyl cellulose (CMC) as a binder, show excellent cyclic retention, with the high specific capacity of 473 mAh g−1 beyond 100 cycles, much greater than that of the bare SnO2 which was also prepared by the hydrothermal method in the absence of MWCNTs. The enhanced capacity retention could be mainly attributed to good dispersion of the tin dioxide particles in the matrix of MWCNTs, which protected the particles from agglomeration during the cycling process. Furthermore, the usage of CMC as a binder is responsible for the low cost and environmental friendliness of the whole electrode fabrication process. 相似文献
19.
Spherical porous tin oxide was fabricated via a spray pyrolysis technique. TEM revealed that the primary SnO2 crystals had an average size of 5-10 nm. Good interconnection between SnO2 crystals is also observed. The electrochemical measurements showed that the spherical porous SnO2 samples have excellent cyclability, which can deliver a reversible capacity of 410 mAh/g for up to 50 cycles as a negative electrode for lithium batteries. Our approach for enhancing the structural stability of tin oxide is to incorporate spherical porous structures as a buffer zone to alleviate the volume expansion of the tin oxide anode during lithiation/delithiation. 相似文献
20.
PSA [poly-(styrene-methyl acrylic acid)] latex particle has been taken into account as template material in SiO2 hollow spheres preparation. TiO2-doped SiO2 hollow spheres were obtained by using the appropriate amount of Ti(SO4)2 solution on SiO2 hollow spheres. The photodecomposition of the MB (methylene blue) was evaluated on these TiO2-doped SiO2 hollow spheres under UV light irradiation. The catalyst samples were characterized by XRD, UV-DRS, SEM and BET. A TiO2-doped SiO2 hollow sphere has shown higher surface area in comparison with pure TiO2 hollow spheres. The 40 wt% TiO2-doped SiO2 hollow sphere has been found as the most active catalyst compared with the others in the process of photodecomposition of
MB (methylene blue). The BET surface area of this sample was found to be 377.6 m2g−1. The photodegradation rate of MB using the TiO2-doped SiO2 catalyst was much higher than that of pure TiO2 hollow spheres. 相似文献