微量溶解氧传感器结构研究

Study of the Structure of a Trace Dissolved Oxygen Sensor

空气中的分子态氧溶解在水中即为溶解氧,是表征水体自净能力和水质监测的重要指标之一,本研究主要介绍了两电极溶解氧传感器的制作过程。对于两电极溶解氧传感器的研制主要包括工作电极、辅助电极和透氧膜的结构、性能的研究。通过实验发现:工作电极的表面积、辅助电极的纯度和表面积会影响传感器测试性能,透氧膜的厚度会影响电极反应速度。由此得出工作电极直径应在5-6 mm之间,辅助电极选用纯银材料,表面积2 200(mm)2左右,选择性透氧膜选用聚四氟乙烯材料,厚度15-25μm之间。

Molecule-state oxygen in air becomes dissolved oxygen when it is dissolved in water and constitutes one of indexes for monitoring water quality,representing an important index indicating the self-purification ability of a body of water. The authors mainly described the fabrication process of a dual-electrode dissolved oxygen sensor. The development of a dual-electrode dissolved oxygen sensor mainly includes the study of the structure and performance of working electrodes,auxiliary electrodes and oxygen penetration membrane. It has been found during the tests that the surface area of the electrode under investigation,purity and surface area of the auxiliary electrode may influence the performance of the sensor being tested and the thickness of the oxygen penetration membrane may affect the reaction speed on the electrodes. From this,one can arrive at a conclusion that the diameter of the working electrode shouldbe between 5 and 6 mm. The auxiliary electrode should choose pure silver materials with their surface area being around 2 200 mm2. The selective oxygen penetration membrane should choose polytetrafluoroethylene material with the thickness being between 15 μm and 25 μm.