A Fundamental Study on Effects of Electric Field on the Reaction Field of Electro-conductive Plate Type Catalyst

电场对催化反应场的影响是：（1）通过直接供给或切断焦耳热，可以方便地控制反应温度;（2）通过改变半导体催化剂的电结构，可以改变催化剂的活性。本研究的最终目的是通过有效地利用导电或半导体催化材料，为每一特定的反应体系设计最佳的催化剂和最佳的反应器，我们制备了两种催化剂，（a）氧化钌（1992）和（B）氧化锌和氧化铋的混合物（1993）。两种催化剂都表现出“变阻器效应”的电压-电流（V-A）的档案。在V-A曲线上，电流跃变的电压称为“可变存储电压”。本文研究了丙酮氧化反应（1000 ppm/空气，275-325 ℃）在外加电作用下的活性。结果表明，激活能和碰撞因子均随外加电压或电流的变化而变化，且在变压器电压附近变化不连续。这些催化活性的变化被认为是由施加电压引起的催化剂本体和表面的固态变化引起的。

The effects of electric field applied on catalytic reaction fields are expected to give (1) Easy control of reaction temperature by direct supply or cut-off of Joule heat and (2) Change of catalytic activity resulted by the change in electric structure of the semiconductor catalyst. The ultimate purposes of this study are to design best catalyst and best reactor for each special reaction system by making effective use of electoro-conductive or semiconductor catalyst materials.We prepared two types of catalyst, (a) Ruthenium oxide (1992), and (b) mixture of Zinc oxide and Bismuth oxide (1993). Both catalyst showed 'varistore effect' on voltage-current (V-A) profiles. The voltage at which the current jumps up on the V-A-Profile is called as 'varistore voltage' Reaction activities for acetone oxidation (1000ppm/air, 275-325ﾟC) under applied electricity were studied. It was shown that both of the activation energy and collision factor changed with applied voltage or current, and the changes were discontinuous around the varistore voltage. These changes of catalytic activities were considered to be resulted by the changes in the solid state of the catlyst bulk and surface induced by the applied voltage.