Assessing the role of GO in enhancing the catalytic activity of MnO2-GO nanomaterials in colorimetric sensors

Abstract

Graphene oxide (GO) has been extensively studied in catalysis due to its high specific surface area and remarkable charge transfer ability. In this work, MnO₂-GO nanomaterial was successfully synthesized by chemical oxidation at room temperature to evaluate the impact of GO on the catalytic activity of MnO₂. The structural properties of MnO₂-GO were investigated by UV-Vis, Raman, TGA, FTIR spectrum, and SEM images indicating that MnO₂ was attached and equally deposited on the GO sheets. Furthermore, CV and EIS analysis showed that GO increased the active surface area and charge transfer rate on the MnO₂-GO coated electrode compared to pure MnO₂ material. The results showed that adding GO help significantly enhanced the catalytic activity in the TMB oxidation reaction. This improvement was indicated by the TMB oxidation reaction confirmed by UV-Vis analysis. The absorption peaks at 450 nm and 650 nm had obvious dissimilitudes and were expressed through the color that could be observed with the naked eye. The obtained results demonstrated that MnO₂-GO has a high application potential for enhancing the catalytic activity in colorimetric sensors.