{(Eu(PW_(11))_2)_m/PEI}多层纳米复合膜的制备和光谱表征

Preparation and Spectrum of Multilayer Films of Polyoxometalate{(Eu(PW_(11))_2)_m/PEI}

在科技竞争日益激烈的今天,功能性分子材料的设计和获得是科学界面临的主要挑战之一。多金属氧酸盐因其具有特定的结构和优越的光、电和磁等物理化学性质,已经成为构造新型功能材料的重要无机构筑块。借助于分子间弱的相互作用将多金属氧酸盐引入到纳米复合薄膜材料中,利用无机和有机组分的协同作用来诱导和产生新的功能特性,必定会给这种无机构筑块在材料科学中的应用创造更多的机会。静电沉积技术是制备有机-无机超薄膜的一种有效方法,人们已经成功地实现了各种无机材料的组装,它们在非线形光学、导电膜、电致发光器件和传感器等方面有着潜在的应用前景。利用层层自组装法(layer by layer self assembly,LBL),制备出有序且稳定的多金属氧酸盐Eu(PW11)2的多层膜。应用紫外光谱研究其层层组装过程,观察到层层组装是一个均一过程。荧光光谱研究表明所制备的含稀土多金属氧酸盐阴离子的多层膜,通过调节膜的厚度、组成和结构,多层膜具有Eu3+的特征发射。这一结果为发光器件的发展提供了丰富的数据。

The layer-by-layer assembly （LBL） is a new method of thin film deposition often used for oppositely charged polyelectrolytes . LBL technique has been extensively used to make multilayer films of polyions with biomolecules such as proteins, enzymes and DNA . It can also be successfully applied to the preparation of thin films of nanoparticles. Ultrathin multilayer films containing a polyoxometalate （Eu（PW11）2）m and PEI were prepared using layer-by-layer assembly method in the present work. The stable multilayer films were assembled by alternate adsorption of negatively charged POM and positively charged polyelectrolytes from their aqueous dispersions. The growth of the multilayer films is regular. The proposed novel immobilized method exhibited good stability and the photoluminescent behavior of films at room temperature was investigated to show the Eu^3＋ characteristic emission pattern, which is important for practical application.