排序方式: 共有17条查询结果,搜索用时 263 毫秒
1.
Hongye Zhang Tianhao Ji Linglong Li Xingyi Qi Yifan Liu Jianwang Cai Haiyan Du Jiayue Sun 《Acta Physico》2008,24(4):607-611
Ni-doped anatase TiO2 nanobelts (NBs) with different Ni2+ contents were simply prepared by combining ion-exchange with hydrothermal treatment. They were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), and magnetic measurement techniques. The results showed that Ni2+ cations doped into the TiO2 lattice and no metallic nickel clusters or nanoparticles could be found. The magnetic results demonstrated that the prepared Ni-doped TiO2 samples had complex magnetic mechanism including room-temperature ferromagnetic and paramagnetic behaviors, and with the increase of Ni2+ content, the magnetization also increased under the same applied field owing to uniform distribution of Ni2+ ions in TiO2 nanobelts. 相似文献
2.
The ultralong Zn2GeO4:Mn2+ persistent luminescence nanobelts (PLNBs) were synthesized using a direct hydrothermal route. The persistent luminescence performance is fine-turned upon prolonging the hydrothermal time and controlling the doping ratio of Mn2+. This solid-statereaction-free chemical approach will promote the broad use of these unique nanostructured PLNBs in developing imaging device. 相似文献
3.
Ying Chen Wolfgang Schuhmann Achim Walter Hassel 《Electrochemistry communications》2009,11(10):2036-2039
The anisotropic electrocatalytic properties of gold nanobelts and nanoplates enclosed by either {1 1 0} or {1 1 1} facets were studied. Different strategies were used to synthesize these materials. It was found that the {1 1 0} surface of gold does not necessarily show a higher electrocatalytic activity than the {1 1 1} surface. The {1 1 0} surface of gold is more active than the {1 1 1} surface for glucose oxidation in both, neutral and alkaline media. However, for methanol oxidation in alkaline solution, the {1 1 0} surface shows a lower activity than the {1 1 1} surface, which is contrary to the general belief that {1 1 0} facet is the most active surface among the three basal planes. The possible mechanisms are discussed. 相似文献
4.
Tingting Lv Dr. Guoyin Zhu Dr. Shengyang Dong Prof. Qingquan Kong Yi Peng Shu Jiang Guangxun Zhang Zilin Yang Prof. Shengyang Yang Prof. Xiaochen Dong Prof. Huan Pang Prof. Yizhou Zhang 《Angewandte Chemie (International ed. in English)》2023,62(5):e202216089
Vanadium-based oxides with high theoretical specific capacities and open crystal structures are promising cathodes for aqueous zinc-ion batteries (AZIBs). In this work, the confined synthesis can insert metal ions into the interlayer spacing of layered vanadium oxide nanobelts without changing the original morphology. Furthermore, we obtain a series of nanomaterials based on metal-confined nanobelts, and describe the effect of interlayer spacing on the electrochemical performance. The electrochemical properties of the obtained Al2.65V6O13 ⋅ 2.07H2O as cathodes for AZIBs are remarkably improved with a high initial capacity of 571.7 mAh ⋅ g−1 at 1.0 A g−1. Even at a high current density of 5.0 A g−1, the initial capacity can still reach 205.7 mAh g−1, with a high capacity retention of 89.2 % after 2000 cycles. This study demonstrates that nanobelts confined with metal ions can significantly improve energy storage applications, revealing new avenues for enhancing the electrochemical performance of AZIBs. 相似文献
5.
ZnO nanorods, nanobelts, nanowires, and tetrapod nanowires were synthesized via thermal evaporation of Zn powder at temperatures in the range 550-600 °C under flow of Ar or Ar/O2 as carrier gas. Uniform ZnO nanowires with diameter 15-25 nm and tetrapod nanowires with diameter 30-50 nm were obtained by strictly controlling the evaporation process. Our experimental results revealed that the concentration of O2 in the carrier gas was a key factor to control the morphology of ZnO nanostructures. The gas sensors fabricated from quasi-one-dimensional (Q1D) ZnO nanostructures exhibited a good performance. The sensor response to 500 ppm ethanol was up to about 5.3 at the operating temperature 300 °C. Both response and recovery times were less than 20 s. The gas-sensing mechanism of the ZnO nanostructures is also discussed and their potential application is indicated accordingly. 相似文献
6.
Wenrou Tian Prof. Najun Li Prof. Dongyun Chen Prof. Qingfeng Xu Prof. Hua Li Prof. Chenglin Yan Prof. Jianmei Lu 《Angewandte Chemie (International ed. in English)》2023,62(33):e202306964
Converting CO2 into high-value C2 chemicals such as acetate with high selectivity and efficiency is a critical issue in renewable energy storage. Herein, for the first time we present a vibration-driven piezocatalysis with tin(II) monosulfide (SnS) nanobelts for conversion of CO2 to acetate with 100 % selectivity, and the highest production rate (2.21 mM h−1) compared with reported catalysts. Mechanism analysis reveal that the polarized charges triggered by periodic mechanical vibration promote the adsorption and activation of CO2. The electron transfer can be facilitated due to built-in electric field, decreased band gap and work function of SnS under stress. Remarkably, reduced distance between active sites leads to charge enrichment on Sn sites, promoting the C−C coupling, reducing the energy barriers of the rate determining step. It puts forward a bran-new strategy for converting CO2 into high-value C2 products with efficient, low-cost and environment-friendly piezocatalysis utilizing mechanical energy. 相似文献
7.
Large-scale Li1+x
V3O8 nanobelts were successfully fabricated using filter paper as deposition substrate through a simple surface sol–gel method.
The nanobelts were as long as tens of micrometers with widths of 0.4–1.0 μm and thickness of 50–100 nm. The nanobelts were
characterized by X-ray diffration (XRD), Fourier infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission
electron microscopy (TEM). The formation mechanism of the nanobelts was investigated, showing that the morphology of the nanobelts
is mainly determined by the calcination temperature. Electrochemical properties of the Li1+x
V3O8 nanobelts were characterized by charge–discharge experiments, and the results demonstrate that the Li1+x
V3O8 nanobelts exhibit a high discharge capacity (278 mAh g−1) and excellent cycling stability. 相似文献
8.
NiS nanobelts of hexagonal phase have been hydrothermally synthesized starting from Ni(CH3COO)2·4H2O and Na2S2O3·5H2O at 200 °C for 12 h. The as-prepared nanobelts were 50 nm thick, 70-200 nm wide and more than 10 μm long. As ethylenediaminetetraacetic acid (EDTA) added, in similar condition, 2 μm NiS2 microspheres of cubic phase were prepared. However, as Ni2+/ ratio was 1:1 and the temperature was decreased to 160 °C, 5 μm NiS2 microspheres constructed of cuboids were formed. 相似文献
9.
α-Fe2O3 nanobelts and nanoflakes have been successfully synthesized by oxidation of iron-coated ITO glass in air. The X-ray diffraction, Raman spectrum and scanning electron microscopy are carried out to characterize the nanobelts and nanoflakes. The formation mechanism has been presented. Significantly, the magnetic investigations show that the magnetic properties are strongly shape-dependent. The magnetization measurements of belt-like and flake-like α-Fe2O3 in perpendicular exhibit ferromagnetic feature with the coercivity (Hc) and saturation magnetization (Ms) of 334.5 Oe and 1.35 emu/g, 239.5 Oe and 0.12 emu/g, respectively. For the parallel, belt-like and flake-like α-Fe2O3 also exhibit ferromagnetic feature with the Hc and Ms of 205.5 Oe and 1.44 emu/g, 159.6 Oe and 0.15 emu/g, respectively. 相似文献
10.
Measuring the aspect ratios of ZnO nanobelts 总被引:2,自引:0,他引:2
Nanobelts are new materials that have a rectangular cross-section and are characterized by widths and width-to-thickness aspect ratios. In this paper, the thickness and aspect ratios of ZnO nanobelts are measured by a conjunction application of convergent beam electron diffraction (CBED) and electron energy-loss spectroscopy (EELS). The thicknesses of thicker nanobelts are first determined by CBED under two-beam diffracting condition, then they are used to determine the electron inelastic mean-free-path (MFP) length, which is 161±15 nm for ZnO at 200 kV. The thicknesses of the thinner nanobelts are then determined by EELS using the calibrated MFP. The results show that the aspect ratio depends on conditions under which the sample was synthesized. 相似文献