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研究了邻氨基酚薄膜对氢离子浓度的响应.采用循环伏安法在石墨基体电极表面得到电沉积邻氨基酚薄膜修饰电极,分别采用直接电位法、循环伏安法、零流电位法研究了该传感器对pH2.00 ～ 12.00范围内的磷酸盐缓冲溶液的电化学响应,直接电位法的电池电动势(Edp)、循环伏安法的还原峰电位(Epc)、零流电位法的还原电流为零时对应的电位(Ezcp)3种电化学信号均与溶液的pH呈线性关系,3种方法的线性回归方程分别为Edp(mV)=50.4 pH-389,Epc(mV) =-60.2pH+75.3和Ezcp(mV)=-45.1 pH+378.常见离子不干扰测定.将3种方法应用于天然水、海水、米醋等实际样品的测定,并与pH玻璃电极的测定结果对照,相对误差在-0.4％～-1.2％区间,相对标准偏差RSD(n =5)在0.25％ ～ 0.71％区间.“,”The responses of electrodeposited o-aminophenol film (OAP/GE) to the concentration of hydrogen ion were studied.The OAP/GE was obtained on the surface of graphite electrode by cyclic voltammetry.The relations between three different potentials and several pHs of phosphate buffer solution in the range of pH 2.00 ～ 12.00 was discussed separately.The three potentials were the potential (Edp) of potentiometry,the reaction peak potential (Epc) of cyclic voltammetry and the zero current potential (Ezcp) of zero current potentiometry.They were linear with the pH of the solution,and the linear regression equations of the three methods were Edp (mV) =50.4 pH-389,Epc (mV)=-60.2 pH + 75.3 and Ezcp (mV) =-45.1 pH + 378,respectively.Three methods were applied to the determination of natural samples such as natural water,sea water and vinegar,and the measured results were compared with those results using pH glass electrode as the sensor.The relative error was in the range of-0.4％ ～-1.2％ and the relative standard deviation RSD (n =5) was in the range of 0.25％ ～ 0.71％.The new sensor,which has many advantages of simple preparation,such as convenient use and short response time,and overcomes the defects of poor reliability of the glass electrode,is expected to be a remote online pH electrochemical sensor.