中文摘要：

在700℃炉冷、870℃空冷和炉冷三种热处理条件下,制备了氧化铱pH微电极,并对比了微电极的线性范围及响应时间。结果表明：热处理条件对Ir氧化物膜的均匀性有很大影响,进而影响其开路电位的稳定性及响应速度。700℃炉冷和870℃空冷制得的电极氧化膜表面粗糙,孔隙率不均匀并伴随有裂纹;而870℃炉冷条件下制得的电极具有表面氧化膜均匀、响应时间短以及线性好等优点。铱氧化物的形成机理是Ir丝被空气中的O2氧化,而高温Li2CO3起到一种溶剂的作用。铱氧化物电极的H^＋响应是由于电极表面水合氧化铱与溶液中H＋发生化学反应,反应为Ir^4＋与Ir^3＋之间的转变。

英文摘要：

Micro IrO2-pH electrodes were prepared under three heat treatment conditions： 700 ℃ furnace cooling, 870 ℃ air cooling and 870 ℃ furnace cooling. Their linear response range and response time were compared. The results indicate that heat treatment conditions have significant effect on the uniformity of iridium oxide films and the open potential stability and response time of the electrodes. After both 700 ℃ furnace cooling and 870 ℃ air cooling, the oxide films have rough surfaces, non-uniform porosities and crevices; whereas after 870 ℃ furnace cooling, the oxide films appear with improved characteristics, such as a more uniformity, a shorter response time and a better linearity of open potential. It is concluded that during iridium oxidation, iridium is oxidized by O2 in air with high temperature Li2CO3 as a solvent. The H^＋ response is caused by the reaction of hydrous iridium oxide on the electrode and H^＋ ions in the solution, resulting in the transition of Ir^4＋and Ir^3＋.