YSZ (Yttria Stabilized Zirconia)-based blended potential type NO2 sensor using porous NiMn2O4 as sensing electrode and preparation method of sensor

Abstract

The invention relates to a YSZ (Yttria Stabilized Zirconia)-based blended potential type NO2 sensor using porous NiMn2O4 as a sensitive electrode and a preparation method of sensor, belonging to the technical field of gas sensors. The sensor is mainly used for detection of automobile exhaust. The sensor consists of an Al2O3 ceramic plate with a Pt heating electrode, a YSZ substrate, a reference electrode and a sensitive electrode in sequence, wherein the reference electrode is a bar-shaped Pt; the sensitive electrode is a bar-shaped NiMn2O4; and the two electrodes are arranged at two sides of the YSZ substrate in symmetry. According to the sensor, a hollow spherical porous NiMn2O4 is prepared by using a solvent evaporation method and is used as the sensing electrode, so that the transmittance of a gas to be tested is improved, and the purpose of improving the sensitivity is achieved.

Description

technical field [0001] The invention belongs to the field of gas sensors, in particular to a porous NiMn 2 o 4 YSZ-based mixed potential NO as a sensitive electrode 2 The sensor and its preparation method are mainly used for the detection of automobile exhaust. Background technique [0002] Nitrogen oxides (NOx) from vehicles x ) is the main cause of urban air pollution. With the rapid growth of car ownership, NO x The resulting environmental problems will become more severe and prominent. For diesel vehicles and gasoline vehicles using lean-burn engines, the traditional three-way catalyst cannot effectively remove NO due to the high concentration of residual oxygen in the exhaust. x , it is necessary to add a storage catalyst to the NO x for absorption, NO must be used in this system x sensor. NO x The sensor plays two roles in the new exhaust treatment system: one is to monitor the combustion state of the engine in real time, and the other is to monitor whether th...

AI Technical Summary

Problems solved by technology

The hybrid potential sensor with NiO as the sensitive electrode produced by the research group of Professor N. Muria, a sensor expert at Kyushu University in Japan, is sensitive to 100ppmNO 2 The mixed potential value of 10 ~ 20mV (Perumal Elumalai, Norio Miura, Performances of planar NO 2 sensor using stabilized zirconia and NiO sensing electrode at high temperature, Solid State Ionics 176 (2005) 2517-2522), one of the main factors limiting the practical use of this sensor is that the sensitivity is not up to practical requirements

One of the main reasons for the low sensitivity in such sensors reported in the literature is that the material is too dense and diffusible, and the gas is consumed in large quantities before reaching the three-phase interface, resulting in a decrease in gas concentration and sensitivity at the three-phase interface.

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