【摘要】 本文报道用铂制作的电量型pH传感器,其原理是铂电极表面上氧化物在形成单分子氧化物覆盖前的覆盖度与溶液pH值之间存在一定的关系,pH值的改变会导致铂表面氧化物覆盖度的改变,并以一定的电量变化为表现形式。在碱性溶液中,该传感器对pH值变化的响应呈线性变化规律,且响应时间小于100 ms,精度小于0.2个pH值。该pH传感器可检测反应过程中pH值的暂态变化,适用于研究电极反应或有中间体生成的反应的机理。该传感器的有效性在用扫描电化学显微镜(SECM)探针-基底伏安模式研究氢氧化镍的充放电的过程中得到验证。更多还原

【Abstract】 A new type of micro pH sensor is established based on coulometric change in the further oxidation and/or reduction of Pt microelectrode with a partially pre-oxidaized surface.The sensor exhibits linear response of its coulometric change to pH change in base solutions.The response time of the sensor to the pH change of solution is less than 100 ms.And the pH detecting accuracy is less than ±0.2 unit.This type of pH sensor is suitable for in-situ detection of transient pH change caused by an electrode reaction,and furthermore,for offering intermediate information of reaction mechanism.The effectiveness of the sensor has been evaluated in the study of the charged and discharged processes of nickel hydroxide material with tip-substrate voltammetry mode of scanning electrochemical microscopy(SECM).更多还原