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1.
Hybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three‐layered Cu2S@carbon@MoS2 as anode materials for sodium‐ion batteries is reported. Through a facile multistep template‐engaged strategy, ultrathin MoS2 nanosheets are grown on nitrogen‐doped carbon‐coated Cu2S nanoboxes to realize the Cu2S@carbon@MoS2 configuration. The design shortens the diffusion path of electrons/Na+ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three‐layered Cu2S@carbon@MoS2 hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life.  相似文献   

2.
Hierarchical MoS2 shells supported on carbon spheres (denoted as C@MoS2) have been synthesized through a one‐step hydrothermal method. The obtained hierarchical C@MoS2 microspheres simultaneously integrate the structural and compositional design rationales for high‐energy electrode materials based on two‐dimensional (2D) nanosheets. When evaluated as an anode material for lithium‐ion batteries (LIBs), the hierarchical C@MoS2 microspheres manifest high specific capacity, enhanced cycling stability and good rate capability.  相似文献   

3.
Hybrid materials, integrating the merits of individual components, are ideal structures for efficient sodium storage. However, the construction of hybrid structures with decent physical/electrochemical properties is still challenging. Now, the elaborate design and synthesis of hierarchical nanoboxes composed of three-layered Cu2S@carbon@MoS2 as anode materials for sodium-ion batteries is reported. Through a facile multistep template-engaged strategy, ultrathin MoS2 nanosheets are grown on nitrogen-doped carbon-coated Cu2S nanoboxes to realize the Cu2S@carbon@MoS2 configuration. The design shortens the diffusion path of electrons/Na+ ions, accommodates the volume change of electrodes during cycling, enhances the electric conductivity of the hybrids, and offers abundant active sites for sodium uptake. By virtue of these advantages, these three-layered Cu2S@carbon@MoS2 hierarchical nanoboxes show excellent electrochemical properties in terms of decent rate capability and stable cycle life.  相似文献   

4.
Rational design and synthesis of advanced anode materials are extremely important for high‐performance lithium‐ion and sodium‐ion batteries. Herein, a simple one‐step hydrothermal method is developed for fabrication of N‐C@MoS2 microspheres with the help of polyurethane as carbon and nitrogen sources. The MoS2 microspheres are composed of MoS2 nanoflakes, which are wrapped by an N‐doped carbon layer. Owing to its unique structural features, the N‐C@MoS2 microspheres exhibit greatly enhanced lithium‐ and sodium‐storage performances including a high specific capacity, high rate capability, and excellent capacity retention. Additionally, the developed polyurethane‐assisted hydrothermal method could be useful for the construction of many other high‐capacity metal oxide/sulfide composite electrode materials for energy storage.  相似文献   

5.
The practical implementation of lithium–sulfur batteries is obstructed by poor conductivity, sluggish redox kinetics, the shuttle effect, large volume variation, and low areal loading of sulfur electrodes. Now, amorphous N‐doped carbon/MoS3 (NC/MoS3) nanoboxes with hollow porous architectures have been meticulously designed as an advanced sulfur host. Benefiting from the enhanced conductivity by the N‐doped carbon, reduced shuttle effect by the strong chemical interaction between unsaturated Mo and lithium polysulfides, improved redox reaction kinetics by the catalytic effect of MoS3, great tolerance of volume variation and high sulfur loading arising from flexible amorphous materials with hollow‐porous structures, the amorphous NC/MoS3 nanoboxes enabled sulfur electrodes to deliver a high areal capacity with superior rate capacity and decent cycling stability. The synthetic strategy can be generalized to fabricate other amorphous metal sulfide nanoboxes.  相似文献   

6.
《Electroanalysis》2017,29(11):2565-2571
MoS2 nanoflakes were prepared by exfoliating commercial MoS2 powders with the assistance of ultrasound and graphene foam was synthesized by chemical vapor deposition using nickel foam as the template. MoS2‐graphene hybrid nanosheets were developed through the combination of MoS2 nanoflakes and graphene nanosheets by ultrasonic dispersion. The hybrid nanosheets were sprayed onto the ITO coated glass, which acts as an electrode for the simultaneously electrochemical determination of levodopa and uric acid. The MoS2‐graphene hybrid nanosheets were characterized by scanning electron microscopy, X‐ray diffraction and Raman spectroscopy. The results show that the hybrid nanosheets are composed of MoS2 and graphene with a sheet‐like morphology. The sensitivity of the electrode for levodopa and uric acid is 0.36 μA μM−1 and 0.39 μA μM−1, respectively. The electrode also shows low limit of detection, good selectivity, reproducibility and stability. And it is potential for use in clinical research.  相似文献   

7.
Uniform Ni3C nanodots dispersed in ultrathin N‐doped carbon nanosheets were successfully prepared by carburization of the two dimensional (2D) nickel cyanide coordination polymer precursors. The Ni3C based nanosheets have lateral length of about 200 nm and thickness of 10 nm. When doped with Fe, the Ni3C based nanosheets exhibited outstanding electrocatalytic properties for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). For example, 2 at % Fe (atomic percent) doped Ni3C nanosheets depict a low overpotential (292 mV) and a small Tafel slope (41.3 mV dec−1) for HER in KOH solution. An outstanding OER catalytic property is also achieved with a low overpotential of 275 mV and a small Tafel slope of 62 mV dec−1 in KOH solution. Such nanodot‐incorporated 2D hybrid structures can serve as an efficient bifunctional electrocatalyst for overall water splitting.  相似文献   

8.
Heteroatom doping is an effective method to adjust the electrochemical behavior of carbonaceous materials. In this work, boron‐doped, carbon‐coated SnO2/graphene hybrids (BCTGs) were fabricated by hydrothermal carbonization of sucrose in the presence of SnO2/graphene nanosheets and phenylboronic acid or boric acid as dopant source and subsequent thermal treatment. Owing to their unique 2D core–shell architecture and B‐doped carbon shells, BCTGs have enhanced conductivity and extra active sites for lithium storage. With phenylboronic acid as B source, the resulting hybrid shows outstanding electrochemical performance as the anode in lithium‐ion batteries with a highly stable capacity of 1165 mA h g?1 at 0.1 A g?1 after 360 cycles and an excellent rate capability of 600 mA h g?1 at 3.2 A g?1, and thus outperforms most of the previously reported SnO2‐based anode materials.  相似文献   

9.
Two-dimensional molybdenum disulfide (MoS2) has been recognized as a promising anode material for lithium-ion batteries (LIBs) due to its high theoretical capacity, but its rapid capacity decay owing to poor conductivity, structure pulverization, and polysulfide dissolution presents significant challenges in practical applications. Herein, triple-layered hollow spheres in which MoS2 nanosheets are fully encapsulated between inner carbon and outer nitrogen-doped carbon (NC) were fabricated. Such an architecture provides high conductivity and efficient lithium-ion transfer. Moreover, the NC shell prevents aggregation and exfoliation of MoS2 nanosheets and thus maintains the integrity of the nanostructure during the charge/discharge process. As anode materials for LIBs, the C@MoS2@NC hollow spheres deliver a high reversible capacity (747 mA h g−1 after 100 cycles at 100 mA g−1) and excellent long-cycle performance (650 mA h g−1 after 1000 cycles at 1.0 A g−1), which confirm its potential for high-performance LIBs.  相似文献   

10.
Hierarchical hybridized nanocomposites with rationally constructed compositions and structures have been considered key for achieving superior Li‐ion battery performance owing to their enhanced properties, such as fast lithium ion diffusion, good collection and transport of electrons, and a buffer zone for relieving the large volume variations during cycling processes. Hierarchical MoS2@carbon microspheres (HMCM) have been synthesized in a facile hydrothermal treatment. The structure analyses reveal that ultrathin MoS2 nanoflakes (ca. 2–5 nm) are vertically supported on the surface of carbon nanospheres. The reversible capacity of the HMCM nanocomposite is maintained at 650 mA h g?1 after 300 cycles at 1 A g?1. Furthermore, the capacity can reach 477 mA h g?1 even at a high current density of 4 A g?1. The outstanding electrochemical performance of HMCM is attributed to the synergetic effect between the carbon spheres and the ultrathin MoS2 nanoflakes. Additionally, the carbon matrix can supply conductive networks and prevent the aggregation of layered MoS2 during the charge/discharge process; and ultrathin MoS2 nanoflakes with enlarged surface areas, which can guarantee the flow of the electrolyte, provide more active sites and reduce the diffusion energy barrier of Li+ ions.  相似文献   

11.
Nitrogen‐doped porous carbon nanotubes@MnO2 (N‐CNTs@MnO2) nanocomposites are prepared through the in situ growth of MnO2 nanosheets on N‐CNTs derived from polypyrrole nanotubes (PNTs). Benefiting from the synergistic effects between N‐CNTs (high conductivity and N doping level) and MnO2 nanosheets (high theoretical capacity), the as‐prepared N‐CNTs@MnO2‐800 nanocomposites show a specific capacitance of 219 F g?1 at a current density of 1.0 A g?1, which is higher than that of pure MnO2 nanosheets (128 F g?1) and PNTs (42 F g?1) in 0.5 m Na2SO4 solution. Meanwhile, the capacitance retention of 86.8 % (after 1000 cycles at 10 A g?1) indicates an excellent electrochemical performance of N‐CNTs@MnO2 prepared in this work.  相似文献   

12.
Compositing amorphous TiO2 with nitrogen‐doped carbon through Ti? N bonding to form an amorphous TiO2/N‐doped carbon hybrid (denoted a‐TiO2/C? N) has been achieved by a two‐step hydrothermal–calcining method with hydrazine hydrate as an inhibitor and nitrogen source. The resultant a‐TiO2/C? N hybrid has a surface area as high as 108 m2 g?1 and, when used as an anode material, exhibits a capacity as high as 290.0 mA h g?1 at a current rate of 1 C and a reversible capacity over 156 mA h g?1 at a current rate of 10 C after 100 cycles; these results are better than those found in most reports on crystalline TiO2. This superior electrochemical performance could be ascribed to a combined effect of several factors, including the amorphous nature, porous structure, high surface area, and N‐doped carbon.  相似文献   

13.
As one member of the emerging class of ultrathin two‐dimensional (2D) transition‐metal dichalcogenide (TMD) nanomaterials, the ultra‐thin MoS2 nanosheet has attracted increasing research interest as a result of its unique structure and fascinating properties. Solution‐phase methods are promising for the scalable production, functionalization, hybridization of MoS2 nanosheets, thus enabling the widespread exploration of MoS2‐based nanomaterials for various promising applications. In this Review, an overview of the recent progress of solution‐processed MoS2 nanosheets is presented, with the emphasis on their synthetic strategies, functionalization, hybridization, properties, and applications. Finally, the challenges and opportunities in this research area will be proposed.  相似文献   

14.
The growth of Li dendrites hinders the practical application of lithium metal anodes (LMAs). In this work, a hollow nanostructure, based on hierarchical MoS2 coated hollow carbon particles preloaded with sulfur (C@MoS2/S), was designed to modify the LMA. The C@MoS2 hollow nanostructures serve as a good scaffold for repeated Li plating/stripping. More importantly, the encapsulated sulfur could gradually release lithium polysulfides during the Li plating/stripping, acting as an effective additive to promote the formation of a mosaic solid electrolyte interphase layer embedded with crystalline hybrid lithium‐based components. These two factors together effectively suppress the growth of Li dendrites. The as‐modified LMA shows a high Coulombic efficiency of 98 % over 500 cycles at the current density of 1 mA cm?2. When matched with a LiFePO4 cathode, the assembled full cell displays a highly improved cycle life of 300 cycles, implying the feasibility of the proposed LMA.  相似文献   

15.
Much attention has recently been focused on the synthesis and application of graphene analogues of layered nanomaterials owing to their better electrochemical performance than the bulk counterparts. We synthesized graphene analogue of 3D MoS2 hierarchical nanoarchitectures through a facile hydrothermal route. The graphene‐like MoS2 nanosheets are uniformly dispersed in an amorphous carbon matrix produced in situ by hydrothermal carbonization. The interlaminar distance between the MoS2 nanosheets is about 1.38 nm, which is far larger than that of bulk MoS2 (0.62 nm). Such a layered architecture is especially beneficial for the intercalation and deintercalation of Li+. When tested as a lithium‐storage anode material, the graphene‐like MoS2 hierarchical nanoarchitectures exhibit high specific capacity, superior rate capability, and enhanced cycling performance. This material shows a high reversible capacity of 813.5 mAh g?1 at a current density of 1000 mA g?1 after 100 cycles and a specific capacity as high as 600 mAh g?1 could be retained even at a current density of 4000 mA g?1. The results further demonstrate that constructing 3D graphene‐like hierarchical nanoarchitectures can effectively improve the electrochemical performance of electrode materials.  相似文献   

16.
We report a novel strategy for the hierarchical assembly of Ag nanoparticles (NPs) on MoS2 nanosheets through coordination by using a multifunctional organic ligand. The presence of Ag NPs on the surface of MoS2 nanosheets inhibits their agglomeration, thereby providing increased interlayer spacing for easy Li+ ion intercalation. Such a unique hybrid architecture also ensures sufficient percolation pathways on the whole surface of the MoS2 nanosheets. Moreover, the high rigidity and low deformability of the Ag NPs effectively preserve the hybrid architecture during the charge–discharge process, which translates into a high cycle stability. A prominent synergistic effect between MoS2 and Ag is witnessed. When the Ag content is only 5 wt %, the Ag–MoS2 hybrid delivers a reversible capacity as high as 920 mA h g?1 at a current density of 100 mA g?1, making the Ag–MoS2 hybrid an attractive candidate for next‐generation LIBs.  相似文献   

17.
Potassium ions batteries (PIBs) have been considered as promising energy storage systems owning to potassium rich natural abundances. However, the difficult reaction kinetics and poor cycling of electrode restrict the further development of PIBs. In this work, antimony anchored in MoS2 nanosheets with N-doped carbon coating (Sb/MoS2/NCs) are prepared and evaluated as anode for PIBs. In the unique Sb/MoS2/NCs structure, the volume expansion of Sb particles could be effectively buffered by the around MoS2 structure. The defects in MoS2 nanosheets provide more electrochemical reaction sites for sufficient K+ insertion/extraction. Furthermore, the N-doped carbon can further accommodate the volume expansion and improve the electronic conductivity of Sb/MoS2/NCs composites. Due to the above advantages, the Sb/MoS2/NCs anode delivers a capacity of 235 mAh/g at 50 mA/g after 78 cycles. This work provides a prospective strategy to design advanced anode materials for PIBs using MoS2 and antimony composites.  相似文献   

18.
以碳纳米纤维(CNFs)作为负载基体和反应器采用静电纺丝技术和碳化工艺生长和调控二硫化钼(MoS_2)纳米片。通过改变前驱体溶液浓度来调控纳米片的形貌和结构,利用MoS_2纳米片的高催化活性和CNFs高比表面积、良好的稳定性以及高电导率的协同作用,研究不同形貌和结构的杂化纳米材料在电催化析氢方面的应用,探索杂化材料形貌与性能之间的潜在规律。运用多种分析测试技术对制备得到的纳米杂化材料进行表征,并对所制备的MoS_2/CNFs杂化材料的电催化析氢性能(HER)进行研究,研究表明近似皮芯结构的MoS_2/CNFs-10杂化材料的电催化析氢性能最好,初始析氢过电位在220 mV,Tafel斜率为110m V·dec~(-1)。  相似文献   

19.
以碳纳米纤维(CNFs)作为负载基体和反应器采用静电纺丝技术和碳化工艺生长和调控二硫化钼(MoS2)纳米片。通过改变前驱体溶液浓度来调控纳米片的形貌和结构,利用MoS2纳米片的高催化活性和CNFs高比表面积、良好的稳定性以及高电导率的协同作用,研究不同形貌和结构的杂化纳米材料在电催化析氢方面的应用,探索杂化材料形貌与性能之间的潜在规律。运用多种分析测试技术对制备得到的纳米杂化材料进行表征,并对所制备的MoS2/CNFs杂化材料的电催化析氢性能(HER)进行研究,研究表明近似皮芯结构的MoS2/CNFs-10杂化材料的电催化析氢性能最好,初始析氢过电位在220 mV,Tafel斜率为110 mV·dec-1。  相似文献   

20.
Immobilization of antibody fragments to 3‐phenoxybenzoic acid (3‐PBA), which are created by disulphide bond (S?S) reduction with tris (2‐carboxyethyl) phosphine (TCEP), is reported atop MoS2 and Cu‐doped MoS2 thin films. MoS2 and Cu‐doped MoS2 thin films are electrodeposited using previously reported methods and tested for their ability to immobilize antibody fragments, before and after annealing in Ar at 500 °C for 3 h. This annealing procedure removes excess sulphur in the as‐deposited films, and creates coordinatively unsaturated Mo sites that are highly reactive towards sulphur, as previously reported for MoS2 hydrodesulphurization catalysts. As demonstrated by electrochemical impedance spectroscopy (EIS) measurements, both annealed MoS2 and Cu‐doped MoS2 thin films adsorb antibody fragments through Mo?S bond formation, unlike the as‐deposited films. Impedance detection of 3‐PBA is reported utilizing antibody fragments bound to both materials, with a sensitivity of 2.7×108 Ω cm2 M?1 and a detection limit of 2.5×10?6 M atop MoS2, and a sensitivity of 5.9×108 Ω cm2 M?1 and a detection limit of 3.8×10?6 M atop Cu‐doped MoS2. The rms surface roughness obtained by atomic force microscopy (AFM) measurements atop annealed MoS2 and Cu‐doped MoS2 ranges from 60–140 nm, so the methods described herein are not limited to ultra‐smooth substrates.  相似文献   

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