Platinum electrode of oxygen sensor and preparation method thereof

Abstract

The invention discloses a platinum electrode of an oxygen sensor. The platinum electrode comprises a platinum electrode matrix and a protective layer attached to the matrix; the protective layer comprises a first protective layer and a second protective layer from the inside to the outside, wherein the first protective layer is formed by sintering a first coat, and the second protective layer is formed by sintering a second coat; the first coat contains yttrium oxide, stable zirconium oxide, magnesia-alumina spinel, adhesive and pore-forming agent; and the second coat contains magnesia-alumina spinel, adhesive and pore-forming agent. The porosity of the protective layer of the platinum electrode of the automobile oxygen sensor can well meet the requirement of air permeability, the platinum electrode has good thermal shock resistance, and the platinum electrode of the oxygen sensor can be effectively prevented from being poisoned, so the service life of the automobile oxygen sensor is prolonged, and the platinum electrode has great significance for the automobile manufacturing industry and environmental protection.

Description

technical field

[0001] The invention relates to a platinum electrode of an oxygen sensor and a preparation method thereof, more particularly, the invention relates to a platinum electrode of an automobile oxygen sensor and a preparation method thereof. Background technique

[0002] In the three-way control system of the automobile engine, the electronically controlled fuel supply unit, the oxygen sensor, and the three-way catalyst are the cores of the control system. In the modern engine EFI system, the most used oxygen sensor is to detect the theoretical air-fuel ratio oxygen sensor, which mainly keeps the engine working near the theoretical air-fuel ratio, so that the three-way catalyst is in the best working range. The oxygen sensor widely used at present is the concentration type zirconia oxygen sensor, which mainly adopts a tubular structure, and the zirconia tube of the sensitive element can be made by injection molding or cold isostatic pressing.

[0003] In actual u...