水和辛胺对ZnO多孔纳米块体孔道结构的影响

以ZnO纳米颗粒为原料,分别用水和辛胺水溶液作为造孔剂,利用溶剂热压方法制备了ZnO多孔纳米块体.实验结果表明,当以水作造孔剂时,随着ZnO纳米粉/水(质量比)比值的减小,ZnO多孔纳米块体的孔径分布变宽,比表面积和孔隙率增加;加入辛胺后,ZnO多孔纳米块体的孔径分布变窄,但比表面积和孔隙率略有减少.随着辛胺用量的增加,比表面积和孔隙率又同时呈上升趋势.对ZnO多孔纳米块体进行的红外吸收测试结果表明,在制备多孔纳米块体过程中,水及辛胺基本上都从样品中逸出,孔道中只有微量残留.

共溶剂对ZnO多孔纳米块体孔径均匀性的影响

以十二烷基硫酸钠(SDS)的水溶液为造孔剂,用溶剂热压方法制备了大孔径的ZnO多孔纳米块体,并进一步考察了添加聚乙二醇400(PEG400)对样品中孔道的影响.实验发现,向十二烷基硫酸钠(SDS)的水溶液中加入聚乙二醇400组成共溶剂后,制备的ZnO多孔纳米块体的孔径大幅度减小,比表面积和孔隙率也明显降低,但孔径的均匀性显著提高.

SDS对ZnO多孔纳米块体孔道结构的影响

以ZnO纳米颗粒为原料,十二烷基硫酸钠(SDS)水溶液作造孔剂,利用我们独有的液态溶剂热压方法制备了ZnO多孔纳米块体.实验结果表明,通过调控SDS溶液的浓度,可以调节ZnO多孔纳米块体的结构参数.当SDS的浓度达到4.34×10-1mol/L时,ZnO多孔纳米块体的孔道空间分布均匀性最好,孔径分布也最窄.另外,红外分析结果表明,在液态溶剂热压制备ZnO多孔纳米块体过程中,SDS在ZnO多孔纳米块体的孔道中有微量残留.

Self-assembly of ZnO nanoparticles and preparation of bulk ZnO porous nanosolids

Novel bulk ZnO porous nanosolids were pre- pared by a unique solvothermal hot-press method, using ZnO nanoparticles and several kinds of solvents as the start- ing materials. It was found from the experiments that ZnO nanoparticles underwent a “self-assembly process” under some specific hydrothermal hot-press conditions. As a result, some “nanoflowers” formed. The results showed that porous nanosolids with uniform pore diameters could be obtained when water distributed uniformly among the ZnO nanopar- ticles. On the contrary, if the uniformity of the distribution of water was poor, “nanoflowers” would appear in the wa- ter-rich region. It was also found that the photoluminescence of ZnO porous nanosolids was affected by the self-assembly phenomenon. In addition, the results also showed that, both the volume and diameters of the pores could be adjusted by changing either the hot-press temperature, pressure or the kinds of solvents.

利用纳米ZnO粉制备厚膜气敏传感器的研究

以ZnO纳米粉(平均粒径30nm)为原料,利用水热热压方法制备了ZnO多孔纳米固体,同时用通常的水热法对ZnO纳米粉进行了预处理(预处理ZnO纳米粉)。然后,分别以ZnO多孔纳米固体和预处理ZnO纳米粉为原料,制备了厚膜气敏传感器。本征电阻的测试结果表明,这两种厚膜气敏传感器的本征电阻比用未经处理的ZnO纳米粉(以下简称“原料ZnO纳米粉”)制备的厚膜气敏传感器大大降低并很快达到稳定状态。有效地改善了器件工作的稳定性。结合对三种传感器的显微结构分析,对出现上述差异的原因进行了讨论。