Cu(II) Metal-Organic Framework Based Electrochemical Sensor for Methanol Quantification in Alkaline Media

Abstract

Metal-Organic frameworks are novel materials with specific pore-size that presents unlimited applications in electrocatalysis and electro-analytical chemistry. The presence of metallic ions in the MOF structure offers a redox active material with electrocatalytical properties in alkaline media towards diverse organic compounds and heavy metals. This property is extensively used to replace enzymes in electrochemical sensors for detecting glucose and other molecules. In this work, we present the synthesis, characterization and application of Cu-BTC MOF as redox active material in a carbon paste electrode (CPE) for methanol electrochemical sensing in alkaline media. The obtained electrode was evaluated for the selective quantification of methanol in ethanol solutions by using diferential pulse voltammetry. The analysis of methanol with the modified electrode presented a LOD, LOQ and sensitivity of 0.04438 mM, 0.1479 mM and 52.74 ± 1.3 μA mM-1 respectively, and a electro-active area of 0.01723 cm2. Our analytical parameters are superior compared with those presented by using enzyme-based electrodes. These results demonstrate the potential use of Cu-BTC@EPC sensors in detecting MeOH at low concentratios, even in presence of ethanol. Figure 1