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TiO2/PtO-Pt复合膜和SnO2/PtO-Pt复合膜氢敏性能的研究 总被引:7,自引:0,他引:7
将PtO-Pt纳米粒子膜与TiO2,SnO2纳米粒子膜复合,利用PtO-Pt纳米粒子膜作 为插入电极和催化剂,设计并研制出一类新型双层结构复合膜气体传感器。采用 TEM和SEM对薄膜的显微结构进行了表征,对空气中4.0H2的氢敏性能研究表明: 200℃时,TiO2/PtO-Pt复合膜对氢气的灵敏度为70%,而TiO2纳米粒子膜无响应。 100℃时,SnO2/PtO-Pt复合膜的灵敏度为92%,同样条件下,SnO2纳米粒子膜的灵 敏度仅为4%。说明PtO-Pt纳米粒子膜的催化作用能够显著提高TiO2和SnO2的膜氢 敏性能。另外,TiO2/PtO-Pt复合膜和SnO2/PtO-Pt复合膜均对空气中H2有很高的选 择性。 相似文献
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合成了新的大环配体12-十八烷基-1, 4, 7, 10-四氮杂环十三烷-11, 13-二酮(odt), 研究了odt的液膜传输Cu^2+的动力学。结果表明传输过程为串联一级反应,k~1=8.1×10^3h^-1, K~2=5.5×10^-2h^-1。载体odt与Cu^2+生成配合物的反应速率比配合物离解反应速率小, 前者为速率控制步骤。传输过程无阴离子参加, 但受溶液酸度控制, 根据酸度的不同, 可将Cu^2+选择性地由低浓度向高浓度传输, 这与细胞对金属离子的主动传输类似。 相似文献
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《Composite Interfaces》2013,20(7):589-603
Three-dimensional (3D) morphology of a polymer/clay nanocomposite, an organophilic montmorillonite (MMT) dispersed in poly(ethylene-co-vinylacetate) (EVA), was examined by transmission electron microtomography (TEMT). Using this technique, individual clay layers dispersed in the EVA matrix were clearly visualized. A volume fraction of the clay layers evaluated from the 3D reconstructed image agreed well with that calculated from the weight of the MMT component in the MMT/EVA system. The individual clay layers were digitally extracted by a newly developed 3D particle algorithm. A size distribution of the clay layers was directly obtained from the 3D reconstruction. Anisotropy of each clay layer was characterized by the determination of three semi-axes of an approximating ellipsoid with the same volume. One of the representative semi-axis of the ellipsoid was used to estimate average orientation of the MMT layers in the ultra-thin section used in the TEMT experiment. Thus, the combination of quantitative TEMT and 3D structural analysis is shown to be a powerful tool to investigate a relationship between the MMT distribution and a variety of physical properties of the nanocomposites. 相似文献
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V-P-O/TiO~2-SiO~2催化剂的制备、表征及其在丙烷氧化制取丙 烯酸反应中的应 用研究 总被引:3,自引:0,他引:3
通过湿磨法,将钒-磷-氧(V-P-O)氧化物负载于钛硅干凝胶(TiO~2-SiO~2)上,制备了V-P-O/TiO~2-SiO~2氧化物催化剂,并运用BET,XRD,TEM及XPS等技术考察了润湿剂,V-P-O的含量及焙烧条件对催化剂结构的影响。由BET方法发现,以异丁醇为润湿剂对催化剂表面积影响较小。XRD和TEM考察结果表明,所制备的催化剂有较高的热稳定性。通过XPS分析,证实钒元素主要以V(IV)价态存在于催化剂的表面。V-P-O/TiO~2-SiO~2催化剂在丙烷氧化反应中显示了良好的催化性能。 相似文献
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