Electrochemical conversion of CO2 to methanol using a glassy carbon electrode, modified by Pt@histamine-reduced graphene oxide.

The electrochemical reduction of CO 2 to value-added products is one of the useful approaches to reducing the effects of global climate change. Herein, a novel electrocatalyst consisting of platinum nanoparticles on histamine-reduced graphene oxide plates (Pt@His-rGO) supported by a glassy carbon (GC) substrate for the electrochemical conversion of CO 2 to methanol has been developed. The nanocomposite was optimized in terms of pH, applied potential, CO 2 purging time and platinum loading for the highest current densities and faradaic efficiencies toward methanol production. The best results were obtained in a solution containing KNO 3 0.1 mol L−1 at the pH of 2.0, the applied potential of −0.3 V vs Ag/AgCl (KCl sat), CO 2 purging duration of 30 min and Pt loading of 5.17 × 10−7 mol cm−2. The faradaic efficiency of 37% was obtained for methanol production. The prepared nanocomposite requires a lower applied potential and serves as an intermediate stabilizer through the production of methanol. Image 1 • Pt@histamine-reduced graphene oxide is synthesized by oxidative diazonium reaction. • The prepared nanocomposite efficiently reduces CO 2 to methanol. • Histamine stabilizes CO 2 on the electrode surface for the optimized reduction. • A quite low applied potential is required for CO 2 electrolysis. [ABSTRACT FROM AUTHOR]