SWAXS investigations on diffuse boundary nanostructures of metallic nanoparticles synthesized by electrical discharges
SWAXS investigations on diffuse boundary nanostructures of metallic nanoparticles synthesized by electrical discharges
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SWAXS 研究放电合成的金属纳米颗粒的扩散边界纳米结构
DOI：
10.1007/s11051-013-2058-7
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发表时间：
2013
影响因子：
2.5
通讯作者：
Hermann Nirschl
中科院分区：
文献类型：
--
作者：
Xiaoai Guo;Alexander Gutsche;Hermann Nirschl
金属纳米粒子由于其独特的尺寸依赖性物理和化学性质，在科学研究和工业应用中引起了特别的兴趣。一种称为放电的环保且具有成本效益的合成方法可以大规模生产金属纳米颗粒。对合成的金属纳米粒子进行系统的研究有助于优化合成工艺，提高产品质量。在这项工作中，我们第一次研究了扩散的界面边界纳米结构的金属纳米颗粒，这是在不同的条件下合成的载气中的电辉光和电弧放电，通过小和广角X射线散射（SWAXS）技术，使用实验室的X射线源。同时，这种独特的SWAXS技术可以同时研究初级颗粒的大小，形态和结晶度。所研究的金属纳米颗粒（铜和镍）覆盖10-80 nm的尺寸范围，并且所确定的金属纳米颗粒的扩散边界纳米结构层的厚度在1-3 nm的范围内。将SWAXS获得的实验结果与TEM/EDX观察结果和来自RRUFF数据库的XRD参考图案进行比较，我们的SWAXS研究表明，在合成的金属纳米颗粒表面上的扩散纳米结构固体层的存在导致散射强度从Porod定律的负偏差，这对应于理想的两个-具有尖锐边界的相粒子系统。这意味着电子密度分布不是尖锐的，而是在两相之间逐渐变化，因此指数α大于4。两个电子密度分布模型，S形电子密度梯度模型和线性电子密度梯度模型，已被考虑在确定的扩散边界纳米结构层的厚度。结合SWAXS实验结果，对辉光放电和电弧放电气相合成金属纳米颗粒扩散边界纳米结构层的可能形成机制进行了详细讨论。
Metallic nanoparticles have attracted a particular interest in scientific research and industrial applications due to their unique size-dependent physical and chemical properties. An eco-friendly and cost-effective synthesis method called electrical discharge enables large scale production of metallic nanoparticles. Systematic investigations of such synthesized metallic nanoparticles help to optimize the synthesis process and improve the product quality. In this work, for the first time we have investigated the diffuse interfacial boundary nanostructures of the metallic nanoparticles, which were synthesized under different conditions by electrical glow and arc discharges in the carrier gas, by means of a small- and wide-angle X-ray scattering (SWAXS) technique using a laboratory X-ray source. Meanwhile, this unique SWAXS technique allows simultaneous study of the primary particle size, morphology, and crystallinity. The metallic nanoparticles (copper and nickel) under investigation cover a size range of 10–80 nm, and the determined thickness of the diffuse boundary nanostructured layer of metallic nanoparticles is in the range of 1–3 nm. The experimental results obtained by SWAXS were compared to the TEM/EDX observation and the XRD reference patterns from RRUFF database, and a good agreement was found. Our SWAXS investigations indicated that the existence of a diffuse nanostructured solid layer on the synthesized metallic nanoparticle surface causes a negative deviation of the scattering intensityfrom Porod’s law which corresponds to the case of ideal two-phase particle systems with sharp boundaries. This implies that the electron density profile is not sharp but changes gradually between two phases, and hence the exponentαis greater than four. Two electron density profile models, sigmoidal electron-density gradient model and linear electron-density gradient model, have been taken into account in determining the thickness of the diffuse boundary nanostructured layer. Combined with the SWAXS experimental results, the possible mechanisms of the formation of the diffuse boundary nanostructured layer of the metallic nanoparticles synthesized by electrical glow and arc discharges in the gas phase have been discussed in detail.
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影响因子：
2.5
作者：
Asbach, Christof;Kaminski, Heinz;Kuhlbusch, Thomas A. J.
通讯作者：
Kuhlbusch, Thomas A. J.
影响因子：
6.1
作者：
D. Britton;E. A. Odo;G. Gonfa;E. O. Jonah;M. Härting
通讯作者：
M. Härting
气溶胶质谱法检测纳米粒子
DOI：
--
发表时间：
2001
期刊：
影响因子：
--
作者：
D. B. Kane;B. Oktem;M. Johnston
通讯作者：
M. Johnston
无机氧化物纳米颗粒功能化纤维素纤维的 SEM 和 TEM 表征
DOI：
--
发表时间：
2010
期刊：
影响因子：
--
作者：
N. Veronovski;S. Hribernik
通讯作者：
S. Hribernik
等离子弧放电法合成纳米锰铝合金
影响因子：
2.1
作者：
Jung;Pubo Li;Chul;X. Dong
通讯作者：
X. Dong