Preparation and Performance Test of Highly Stable Ammonium Ion Selective Electrode Based on Hydrophobic Solid Contact Layer
10.19756/j.issn.0253-3820.241496
- VernacularTitle:基于疏水固态接触层的高稳定性铵离子选择电极的制备及性能测试
- Author:
Chen-Yu LIU
1
;
Jia-Wen YIN
;
Yun-Zhe HAN
;
Sheng-Kang LU
;
Qing-Hui JIN
Author Information
1. 宁波大学信息科学与工程学院,宁波 315211
- Keywords:
Ammonium ion selective electrode;
Hydrophobic solid contact layer;
Perfluorooctanoic acid;
Water layer
- From:
Chinese Journal of Analytical Chemistry
2025;53(5):774-784
- CountryChina
- Language:Chinese
-
Abstract:
The stability of ammonium ion selective electrode is an important indicator to ensure accurate monitoring of ammonia nitrogen concentration in drinking water.However,in long-term monitoring process,interfering ions and water molecules in water samples may penetrate into the interior of the ammonium ion selective electrode to form a water layer,which affects the potential response and stability of the electrode.Perfluorooctanoic acid is a low surface energy material,and doping it in polyaniline can reduce surface energy of the composite and improve surface roughness.In this work,five ammonium ion selective electrodes were prepared by doping polyaniline with different concentrations of perfluorooctanoic acid as a solid contact layer,which made the solid contact layer of electrode had hydrophobic properties,thereby improving stability of the ammonium ion selective electrode.The stability of the ion-selective electrode was evaluated by potential drift experiment,and the optimal doping concentration of perfluorooctanoic acid in the sediment solution was determined to be 5 mmol/L.The experiment results showed that the solid contact layer had a water contact angle of 132o under the doping concentration,the potential drift rate was 41.66 μV/h,and potential drift rate in the aqueous layer test was 1.31 mV/h,which were all better than those of the unmodified electrode.The standard deviation of the electrode potential was 1.42 mV,which was obviously superior to that of the unmodified electrode.The characteristics of high stability of the electrode made it suitable for long-term monitoring of ammonia nitrogen content in water samples.
