Cobalt oxide nanoparticles based carbon electrode for the detection of residual nitrite in the soil of agricultural fields

In the past few decades, accumulation of excess fertiliser in soil leads to deterioration of soil quality with carcinogenic effects on animals and humans. Hence, a quick, effective and reliable method of nitrite detection is necessary. In this regard, cobalt oxide nanoparticle-based carbon electrodes have excellent sensitivity towards electro-catalytic detection of nitrite ions. In this research, cobalt oxide nanoparticles were synthesised by precipitation reaction followed by calcination. Various spectroscopic methods have been used for the characterisation of nanomaterial, such as TEM, SEM-EDAX, FT-IR and XRD. A carbon-based electrode was developed using cobalt oxide, graphite and silicon oil. The electrode showed a good sensitivity towards detection of nitrite with limit of detection 0.3 µm and wider linear range. Due to low-cost preparation, sensitivity towards NO2− ions and high conductivity, the sensor can be employed for the detection of nitrite in agricultural field soil samples. © 2022 Informa UK Limited, trading as Taylor & Francis Group.