TiO2基稀磁半导体二维纳米阵列的构筑及其形态相关的磁性研究

Diluted Magnetic Semiconductor(DMS)nanoarray incorporates charge and spin properties of electron in a nanostructure, the charge and spin of the carrier can be tuned in a multi-freedom-degree means by the structural parameters of the arrays, such as morphology, size and periodicity etc., which exhibits attractive application prospect in the field of novel spin-based device.Based on our previous work,a new strategy for fabricating TiO2-based DMS two-dimensional nanoarrays via monolayer colloidal crystal template is proposed to synthesis a lagre area naonoarrays with highly uniform morphology and chemical composition.The effects of synthesis parameters and post-heat treatment process on the growth of the array are investigated to achieve large-scale controll of the morphology (such as hole,ring,bowl etc.), size and periodicity of the array structural parameters. A comprehensive study on the magnetic properties of nanoarray with different structural parameter is to search the relationship between magnetic properties and array structural parameters, and further to explore the internal mechanism influenced magnetic properties of DMS material. This project aims to develop a facile new technology for synthesis and controllable morphology of DMS nanoarray. We will establish the relationship between structural parameters of array and magnetic properties to achieve the controllable magnetic properties of the array, which may provide a new route for further investigating the origin of magnetic properties of DMS materials and also provide a new idea for designing novel micro-nano device.

稀磁半导体纳米阵列可将电子的电荷和自旋特性集于同一种纳米结构中，通过调节阵列的形貌、尺寸和周期等结构参数,有望实现对载流子自旋和电荷的多自由度调控，在新型自旋电子器件领域具有诱人的应用前景。本项目在前期工作基础上，提出了基于单层胶体晶体模板构筑TiO2基稀磁半导体二维纳米阵列的新策略，合成大面积表面形态和化学成分高度均一的纳米阵列,揭示制备条件和后期热处理工艺对纳米阵列生长的影响，实现阵列形貌（如孔、环、碗等）、尺寸和周期等阵列结构参数的大范围调控；系统研究不同结构参数纳米阵列的磁性，探寻阵列结构参数与磁性之间的关系，进一步探究影响材料磁性的内在机制。本项目研究旨在发展一种简便实用的稀磁半导体纳米阵列的合成新技术和形态调控的新方法，建立阵列结构参数与磁性之间的关联，初步实现阵列磁性的调控，为深入研究稀磁半导体材料磁性起源的内在机理提供新途径，为新型微纳米器件的设计提供新思路。

稀磁半导体纳米阵列兼具材料的半导体和磁学特性，通过调节纳米阵列结构参数，有望实现稀磁半导体纳米材料的物性调控，从而促进稀磁纳米材料在新型自旋器件中的应用。项目以单层胶体晶体为模板，结合溶液浸渍法、磁控溅射法等方法，制备稀磁半导体二维纳米阵列，系统研究了制备参数和后期处理条件对纳米阵列形态的影响，探索纳米阵列的形成机制，实现了孔状、环状和碗状等纳米阵列的可控构筑；结合模板法制备纳米阵列形态可调控的特点，研究了不同形态二氧化钛、氧化锌纳米阵列的磁性，发现了氧空位缺陷诱导的室温铁磁性能，形态相关的磁学性能其实质取决于材料中缺陷态的浓度和类型；进一步发展胶体晶体模板方法，成功合成了硫化锌纳米碗、氧化锌空心球等阵列，并对其光学性质进行研究。本项目发展了一种简便实用的稀磁半导体纳米阵列合成方法，这种方法在制备其它材料纳米阵列时具有普适性。纳米阵列形态相关的物性研究，为深入研究影响材料物性的内在机制提供了新途径，为新型微纳器件的研发提供新思路。