Cuprous oxide and Ag modified titanium dioxide electrode for ultra-sensitive detection of ammonia nitrogen

Abstract

In this study, a self-supporting cuprous oxide and Ag modified titanium dioxide nanotubes (Ag/Cu2O/TNTs) sensor was constructed by electrochemical method for the ultra-sensitive detection of ammonia nitrogen under neutral conditions. The petal-like “cuprous oxide” and “leaf-like” silver nanoparticles grown on titanium dioxide nanotube arrays can significantly enhance the electrochemical effective area and electrocatalytic performance of the composite electrode. Notably, Ag/Cu2O/TNTs sensor was successfully used for the determination of ammonia nitrogen at low concentrations under neutral conditions in the range of 0.1–101 μM with a corresponding detection limit of 0.074 μM. The obtained sensor demonstrated reliable recoveries (97.30 % to 103.8 %) and RSD (1.46 % to 1.83 %) in the analysis of real samples. It provides a fast and accurate method for the detection of ammonia nitrogen at low concentrations in real waters. It is expected to be suitable for the real-time detection because of its excellent immunity to interference, repeatability and stability.