열화학적 방법에 의한 산소센서용 세리아 나노분말 합성

Abstract

The nanostructured cerium oxide powders were synthesized by spray thermal decomposition process for the use as the raw materials of resistive oxygen sensor. The synthesis routes consisted of 1) spray drying of water based organic solution made from cerium nitrate hydrate (Ce(NO3)36H2O) and 2) heat treatment of spray dried precursor powders at 400℃ in air atmosphere to remove the volatile components and identically to oxidize the cerium component. The produced powders have shown the loose structure agglomerated with extremely fine cerium oxide particles with about 15 nm and very high specific surface area (110 ㎡/g). The oxygen sensitivity, n (Log∝Log (PO2/Po)-n and the response time, t90 measured at 600℃ in the sample sintered at 1000℃, were about 0.25 and 3 seconds, respectively, which had much higher performances than those known in micron or 100~200 nm sized sensors.