Novel ceramic catalytic electrode and preparation method thereof

Abstract

The invention discloses a novel ceramic catalytic electrode and a preparation method thereof. The novel ceramic catalytic electrode comprises a catalytic electrode ceramic matrix and precious metals arranged in the catalytic electrode ceramic matrix and on the surface of the catalytic electrode ceramic matrix, the catalytic electrode ceramic matrix is porous ceramic with tiny three-dimensional pore channels in the interior and on the surface, and the precious metals are distributed in the porous ceramic in a three-dimensional net shape. One purpose of the invention is to provide a novel ceramic catalytic electrode with low cost and high performance. The number of three-phase interfaces among precious metal, porous solid electrolyte ceramic and oxygen is greatly increased due to the structure, so that the novel ceramic catalytic electrode also has excellent catalytic capability under the condition of using a small amount of precious metal, and the production cost is greatly reduced. Another purpose of the invention is to provide a preparation method of the novel ceramic catalytic electrode, and the ceramic electrode prepared by the method is simple in process operation, good in combinability of the electrode material and the ceramic substrate, and less in precious metal consumption.

Description

technical field [0001] The invention relates to the field of oxygen sensors, in particular to a ceramic catalytic electrode and a preparation method thereof. Background technique [0002] In the control system of the vehicle engine, ensuring that the engine works with the mixture of the best air-fuel ratio is a key technology for emission control. The vehicle oxygen sensor is a key component for controlling the air-fuel ratio of the engine mixture. The oxygen sensor is Feedback the gas condition after mixed combustion of oil and gas to a key component of the engine control unit (ECU) in real time. The engine electronically controlled injection system precisely controls the air-fuel ratio (A / F, the mass ratio of air to gasoline) based on the signal provided by the oxygen sensor. . [0003] The three-way catalytic converter is the most important external purification device installed in the automobile exhaust system. It can convert harmful gases such as CO, HC and NOx emitted...

AI Technical Summary

Problems solved by technology

For electroplating electrode technology, refer to the publication specification of invention patent application CN200310114168.7, etc. The advantages of electroplating electrodes are that the prepared electrode layer is very thin, the dosage is small, and there are more three-phase interfaces and good activity, which effectively solves the problem of the amount of noble metal used in co-fired electrodes. There are many problems, but the bonding reliability between the electrode material and the substrate is relatively poor, and it is easy to peel off; and the electroplating process is relatively complicated, and it is easy to pollute the environment

[0007] The co-firing technology of electrodes and solid electrolyte ceramics refers to application number 200410064804.4, etc. The advantage of co-fired electrodes is that the bonding reliability between the electrode layer and the substrate is better, and the problem of easy peeling off of the electrode layer directly coated is improved. A thick film is used, with a thickness of 6-10 microns. The platinum particles are micron-scale or sub-nano-scale noble metal particles, and the electrode material is co-fired at a high temperature of 1400-1550°C. The low-temperature catalytic activity of the electrode is relatively poor. At the same time, the three-phase The interface also has a certain loss, so under the condition of obtaining the same catalytic activity, more precious metals are needed, and the cost is high

Images