基于铂薄膜电极的电化学型甲醛传感器

Formaldehyde electrochemical sensor based on a Pt thin-film electrode

制做了液相体系中以铂薄膜电极作为工作电极的甲醛电化学传感器。利用x射线衍射（XRt））和场发射扫描电子显微镜（FESEM）对铂薄膜电极的物相和表面形貌进行表征。在外加电压为0．7V，电解液H：SO。溶液浓度为0．1 mol／L时，传感器的响应信号与甲醛浓度在0．561～18．71μmol／L之间呈现良好的线性关系，线性方程为Y=0．4085c＋2．746（R2=0．9904），传感器对甲醛的响应时间（T90）约为60S。

A kind of the formaldehyde electrochemical sensor based on Pt thin-film electrode which served as the working electrode was discussed. The phase composition and surface morphology of the Pt thin-film electrode were characterized by X-ray diffraction （XRD） and field emission scanning electron microscope （FESEM）. The electrocatalytie activity of the working electrode for formaldehyde detection in acid solution was investigated via a series of electrochemical measurements. Moreover, the optimal working environment of sensor had also been investigated. It showed a good linear relationship between response signal of the sensor and the formaldehyde concentration in the range of 0. 561 ~ 18.71 μmol/L at an applied potential of 0. 7V in the 0. 1 mol/L sulfuric acid solution. The linear regress equation was Y = 0. 4085c ＋ 2. 746（ R2 = 0. 9904）, and the 90% response time was about 60 s. Selectivity and repeatability of the sensor were further evaluated. The results indicated that the sensor had high sensitivity and repeatability. The as-prepared electrode is promising for a formaldehyde electrochemical sensor.