Metal-Organic-Framework-Based Electrochemical Nanosensor for Hydrogen Peroxide

Electrochemical applications of metal organic frameworks (MOFs) are of considerable current interest. Due to the large surface area exposed to solution, MOFs are potentially useful electrode materials for sensing inner-sphere analytes, such as reactive oxygen species. Herein, we electrodeposited copper benzene tricarboxylate MOF (HKUST-1) into the cavity of an open carbon nanopipette (CNP) to produce a CNP-MOF nanoelectrode. Unlike electronically conductive metal or carbon electrodes, the electrochemical response of CNP-MOFs relies on oxidation/reduction of Cu(I)/Cu(II) nodes in the porous nanostructure. Nevertheless, sigmoidal steady-state voltammograms with a well-defined plateau current have been recorded for simple redox mediators, for example, ferrocenemethanol. A linear calibration curve obtained for the hydrogen peroxide reduction suggests that CNP-MOFs can potentially be useful as nanosensors for peroxide.

Automated summary

Metal organic frameworks (MOFs) have attracted considerable interest in electrochemical applications, particularly as electrode materials for sensing analytes. In this study, copper benzene tricarboxylate MOF (HKUST-1) was electrodeposited into an open carbon nanopipette (CNP) to create a CNP-MOF nanoelectrode. The electrochemical response of CNP-MOFs relies on oxidation/reduction of Cu(I)/Cu(II) nodes in the porous nanostructure, and it shows a linear calibration curve for hydrogen peroxide reduction, suggesting its potential as a nanosensor.