电爆炸丝法产生nm粉末及负载型nm催化剂

Synthesis of Nanosize Powders and Nanosize Composite Catalyst by Electrical Exploding Wires

为了探索电爆炸金属丝技术在制备纳米粉末及其相关产品中的应用前景,利用电爆炸金属丝法成功制备了平均粒度分别达到65 nm和44 nm的纳米Al2O3和TiO2粉末,通过X射线衍射和电子衍射分析,Al2O3粉末为γ-Al2O3,TiO2粉末由金红石和锐钛矿组成。研究了实验条件对产生粉末粒度的影响及其规律后探索了电爆炸丝法产生负载型纳米催化剂的实验条件,并成功制备了负载型纳米TiO2催化剂,其化学实验结果表明:与现有催化剂比较,该催化剂能使某类化学反应的速度提高>50%,反应产物的选择性提高>3%。

Nanometer powders of Al2O3 and TiO2 were produced by electrical explosion of wires （EEW）. The size distribution and average size of powders were measured by a Malvern Zetasizer-Nano analyzer. The results of measurement show that the average size of Al2O3 powders is 65 nm and average size of TiO2 powders is 44 nm. The composition of powders was analyzed by X-ray diffraction （XRD） and electron diffraction. The particles of Al2O3 powder were γ- Al2O3 and the particles of TiO2 powders were composed of Anatase and Rutile. The effects of the experimental conditions on the powders size have been studied and the rule has been concluded： （1 ） the gas pressure in exploding chamber affects the particle size, the lower the pressure is, the smaller the particle size is; （2） the particle size is proportional to the wires diameter, the smaller the wire＇s diameter is, the smaller the particle size is; （3） the particle size has some relations with the storage energy of the capacitor, the average size varies non-linearly with the storage energy of capacities. Moreover, synthesis of nanometer composite catalyzer by electrical explosion of wires was investigated. Nanometer TiO2 composite catalyst was synthesized successfully by EEW. The experimental results showed that the new type of catalyst has superiority in accelerating certain reactions and selecting the reactions production, compared with customary catalyst.