In-situ synthesis of N-doped carbon-encapsulated Co particles for electrochemical glucose sensing

Precise monitoring is of great significance for diabetes management. In contrast to enzyme-based glucose sensors, nonenzymatic ones offer advantages such as improved stability, higher sensitivity, and reduced manufacturing expenses. In the present research, nitrogen-doped carbon nanotube-encapsulated cobalt particles (Co@NCTs-800) were synthesized via a high-temperature pyrolysis and applied to high-efficiency glucose detection. This material benefits from a large number of Co 4+ active sites formed by electrooxidation, along with the high surface area and conductivity of the N-doped carbon nanotube matrix. As a result, Co@NCTs-800 showed outstanding electrocatalytic properties, achieving remarkable sensitivity reaching up to 141.3 μA mM −1  cm −2 , a rapid response duration of merely 1.9 s, along with a minuscule detection threshold of 2.3 μM. The sensor also demonstrated strong resistance to various interfering substances, good stability and reproducibility (RSD = 3.24%). Furthermore, reliable glucose detection in real beverage samples confirmed the practical applicability of the proposed sensor. The successful fabrication of cobalt particles encapsulated in nitrogen-doped carbon nanotubes offered in-depth understanding regarding the advancement of highly efficient non-enzymatic electrochemical glucose sensing.