Preparation And Properties Of Micron/nano-wires Sensor Materials

In recent years, the scientific technology revolution leads to the developing of the information industry, especially the fast popularize and spread of the internet technology, which makes the electronic device to a trend toward mini-type, multifunctional, integration and intelligent. The industrial advances place greater demands on the material of sensors, like response speed, response accuracy, repetitiveness and stability. Many researchers are focus on finding the new sensor materials), the major work in this paper is about gas sensor material (ZnO nanostructure) and FeNi composite wire which can be used in magnetic materials. ZnO nano flowers were successfully prepared by a new non-catalytic method based on directly heating of Zn strip using a direct current power supply. The Zn strip was obtained by electro-depositionon silicon wafer with laser etching. The other major work is finding the method which can be used to improve the rate of change of GMI ratio. The main findings of the present study were as follows:The GMI of FeNi composite wire obtained by eletrodeposition has been investigated for the frequency range of40Hz-110MHz, bias field up to85Oe, with or without tensile stress applied. The giant magnetoimpedance effect ratio under different stress is increased obviously. New results on the giant magnetoimpedance effect ratio in soft magnetic composite wire are presented. The giant magnetoimpedance effect ratio reached almost13000at146.5MPa, which is a new discovery. The maximum value of giant magnetoimpedance ratio changed in a special way, first increased then decreased, the frequency of maximum ratio decreased as stress applying. The applied of stress could exstrodinary improve giant magnetoimpedance ratio and decreased frequency, which can be used in higher-performance devices. The FeNi composite wire was applied by low-current, which can create toroidal magnetic field, the configuration of magnetic moment will tend toward to circumference in composite wire. As a result, transverse permeability will be increased. Tests indicates that the giant magnetoimpedance effect ratio reached almost900%after applying the current of100mA. ZnO nano flowers have been obtained by simply heating metallic zinc for a few seconds, which is synthesized by electro-deposition on silicon with laser etching. The nano flowers, with a size of more than15μm, are assembled by nanowires with a length of10μm and a diameter of100nm, and the length-diameter ratio was about100. The nano flowers are made up of nanowires with high length-to-diameter ratio, which may be useful for field-emission and gas sensor and nanogenerator applications in future.