Self-catalyzed nitrogen-doped carbon nanotubes connected FeCo nanostructures for electrochemical sensitive detection...

Metol is a photographic developer that is extremely toxic to aquatic organisms due to its widespread use and improper handling in aquatic environments. Therefore, it is urgent to develop reliable strategies for its detection. Herein, we have designed an efficacious, expeditious and dependable electrochemical sensors for electrochemical determination of metol based on a self-catalyzed nitrogen-doped carbon nanotubes connected FeCo nanostructures (denoted FeCo@NC). The FeCo@NC formed from MOF-on-MOF hybrids of FeCo-MOF@ZIF-8. The porous structure formed by ZIF-8 after pyrolysis enhances diffusion kinetics, while the large number of carbon nanotubes produced by ZIF-8 has a beneficial impact on the field of electrocatalysis. The large electrically active surface area, rapid electron transfer rate and high electrocatalytic capacity exhibited by FeCo@NC were utilized to construct a highly sensitive sensor for the determination of metol. The limit of detection was found to be 0.024 μM, with a linear range of 0.08-450 μM. Furthermore, the developed sensor demonstrated excellent catalytic activity for the detection of metol, along with stability, reproducibility and selectivity. The sensor was employed for the analysis of water samples, yielding promising recovery results.