Two Electron Transfer Mediated Enhanced Electrochemical Nitrate Detection by Sn‐Doped Cuxo Thin Film Electrode

Abstract

Abstract The unique electrochemical and electronic properties of CuxO (Cu2O/CuO) give it merit to be used in the development of electronic devices. This paper presents the facile chemical route for the development of a sensitive, accurate, and low‐cost nitrate electrochemical sensor based on undoped and Sn‐doped CuxO thin film electrodes. Various characterization techniques are used to study the physical, electro‐chemical, and electronic properties of the material. Sn‐doping resulted in an increase in the number of electron transfers from 1 to 2 as compared to undoped CuxO. The prepared sensor exhibited a high sensitivity of 100.3 µA mm−1 cm−2, a wide linear concentration range of up to 50.0 mm, a fast response time of <5.0 s is observed at a potential of −1.0 V (vs Ag/AgCl), and a very low limit of detection of 0.1 µm (S/N = 3.0) that outperformed those in the recent literature. The electrode is selective for nitrate in the presence of common interference species and exhibited chemical stability and reproducibility.

Keywords

• electrochemical sensors
• metal–organic decomposition
• Sn‐doping
• spin‐coating
• thin films