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利用Raman光谱对结晶紫(Crystal Violet,CV)在纳米磷化镓(GaP)粉体表面的吸附状态进行了分析.结果表明:与普通拉曼散射谱(Normal Raman Scattering,NRS)相比,结晶紫表面增强拉曼散射(Surface Enhanced Raman Scattering,SERS)谱的4种振动模式,即:中央键的呼吸振动、环-C -环面外弯曲振动、环C-H面外弯曲振动以及N-环伸缩振动,在纳米GaP粉体表面得到增强;通过分析吸附前后结晶紫拉曼散射峰相对强度的变化,确定了结晶紫在纳米GaP粉体表面的吸附取向,并对其表面增强散射机理进行了探讨. 相似文献
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Effect of double AlN buffer layer on the qualities of GaN films grown by radio-frequency molecular beam epitaxy 下载免费PDF全文
This paper reports that the GaN thin films with Ga-polarity and high quality were grown by radio-frequency molecular beam epitaxy on sapphire (0001) substrate with a double A1N buffer layer. The buffer layer consists of a high-temperature (HT) A1N layer and a low-temperature (LT) A1N layer grown at 800℃ and 600℃, respectively. It is demonstrated that the HT-A1N layer can result in the growth of GaN epilayer in Ga-polarity and the LT-A1N layer is helpful for the improvement of the epilayer quality. It is observed that the carrier mobility of the GaN epilayer increases from 458 to 858cm^2/V.s at room temperature when the thickness of LT-A1N layer varies from 0 to 20nm. The full width at half maximum of x-ray rocking curves also demonstrates a substantial improvement in the quality of GaN epilavers by the utilization of LT-A1N layer. 相似文献
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在液镓电极上,反丁烯二腈(FDN)的电氢化二聚(EHD)不仅能在含离子型表面活性剂如四乙基对甲苯磺酸铵(TEA-PTS)溶液中发生,同样也能在含低浓度的强表面活性剂如TritonX-100溶液中进行,在不含有机表面活性剂的溶液中,FDN在滴镓电极上产生一个2电子还原波,生成为丁二腈的饱和单体。在水溶液中加入一定浓度的TEA-PTS或低浓度的TritonX-100时,原来的2电子还原波分裂成两个连续 相似文献
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Jan ?echal Jind?ich Mach Stanislav Voborný Petr Kostelník Petr Bábor Ji?í Spousta Tomáš Šikola 《Surface science》2007,601(9):2047-2053
Results for deposition and thermal annealing of gallium on the Si(1 0 0)-(2 × 1) surface achieved by synchrotron radiation photoelectron spectroscopy (SR-PES) and low energy electron diffraction (LEED) are presented. In addition to deposition of Ga on a clean surface, the influence of water adsorption on the arrangement of gallium atoms was also studied. The results on Ga deposition at a higher temperature (490 °C) are consistent with a Ga ad-dimer model showing equivalent bond arrangement of all Ga atoms for coverages up to 0.5 ML. The deposition onto a surface with adsorbed water at room temperature led to a disordered gallium growth. In this case gallium atoms bind to silicon dimers already binding fragments of adsorbed water. A subsequent annealing of these layers leads to a surface structure similar to the Ga-(2 × 2), however, it is less ordered, probably due to the presence of silicon oxides formed from water fragments. 相似文献
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Subvalent Gallium Triflates – Potentially Useful Starting Materials for Gallium Cluster Compounds By reaction of GaCp* with trifluormethanesulfonic acid in hexane a mixture of gallium trifluormethanesulfonates (triflates, OTf) is obtained. This mixture reacts readily with lithiumsilanides [Li(thf)3Si(SiMe3)2R] (R = Me, SiMe3) to afford the cluster compounds [Ga6{Si(SiMe3)Me}6], [Ga2{Si(SiMe3)3}4] and [Ga10{Si(SiMe3)3}6]. By crystallization from various solvents the gallium triflates [Ga(OTf)3(thf)3], [HGa(OTf)(thf)4]+ [Ga(OTf)4(thf)3]−, [Cp*GaGa(OTf)2]2 and [Ga(toluene)2]+ [Ga5(OTf)6(Cp*)2]− were isolated and characterized by single crystal X ray structure analysis. 相似文献