Non-enzymatic electrochemical hydrogen peroxide sensing using a nanocomposite prepared from silver nanoparticles and copper (II)-porphyrin derived metal-organic framework nanosheets

A non-enzymatic hydrogen peroxide (H2O2) electrochemical sensor material was prepared from silver nanoparticles and a 2D copper-porphyrin framework (MOF). The structure and morphology of the nanocomposite were characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The results showed that the MOF has a two-dimensional sheet structure, and a large number of Ag NPs are uniformly attached to it. The MOF also acts as a peroxidase mimic. The sensor has excellent catalytic performance in terms of H2O2 reduction. Figures of merit include (a) an electrochemical sensitivity of 21.6 mu A mM(-1) cm(-2) at a typical working potential of -0.25 V (vs. SCE), (b) a detection limit of 1.2 mu M (at S/N = 3), and (c) a linear response range that extends from 3.7 mu M to 5.8 mM. Compared to other sensors of the same type, the linear range of the sensor is extended by an order of magnitude.