A novel electrochemical sensor based on Pb0.95Ti0.05O-decorated nitrogen self-doped biochar for highly sensitive and selective detection of carvacrol

Carvacrol has widely used in the field of medicine and sterilization. Thus, developing reliable, efficient, and rapid method for the carvacrol detection is meaningful. In this study, we fabricated a carvacrol sensor based on Pb0.95Ti0.05O decorated with nitrogen self-doped biochar (Pb0.95Ti0.05O/NC), which was synthesized by hydrothermal and carbonization of soybean root nodules, respectively. The prepared sensor exhibited better electrochemical performances than that of PbO, Pb0.95Ti0.05O, NC. The fabricated Pb0.95Ti0.05O/NC sensor exhibited a wide detection range from 0.1 to 190 µM and a low detection limit of 0.054 µM. The excellent electrochemical performances were attributed to the increased electron density and electron mobility after the introduction of Ti doping and nitrogen doped carbon. Mechanistic studies revealed that the electrochemical oxidation of carvacrol involves one electron and was limited by adsorption process. The sensor demonstrated good stability, anti-interference, reproducibility, and good repeatability. Moreover, the sensor displayed excellent recovery rates ranging from 92.7% to 102.9% when applied to the detection of carvacrol in real samples, making it a promising candidate for practical applications in the sensitive detection of carvacrol.