Nickel 2-Methylimidazole Metal-Organic Framework Ultrathin Nanosheets/Titanium Carbide MXene Hybrid Nanostructure as a Bifunctional Electrocatalyst for Methanol and Urea Oxidation Reactions

In the development of direct methanol and direct urea fuel cells, efficient electrocatalytic methanol oxidation reaction (MOR) and urea oxidation reaction (UOR) are employed. These approaches are essential in fuel cell technology for addressing the rising global energy and environmental concerns. In this research, nickel 2-methylimidazole metal-organic framework (Ni-MOF) and Ni-MOF-integrated titanium carbide (Ti3C2) MXene hybrid nanostructures (Ni-MOF/Ti3C2) were controllably synthesized via a facile solvothermal method. Ti3C2 MXene nanosheets are utilized as two-dimensional support to enhance the catalytic activity of the Ni-MOF/Ti3C2 hybrid nanostructure. Furthermore, the methanol and urea electro-oxidation activity of the Ni-MOF/Ti3C2 hybrid nanostructure is investigated. The synergistic effect between Ni-MOF and Ti3C2 MXene resulted in excellent and durable electrochemical performance. Thus, the newly synthesized electrode material exhibited high electrocatalytic activity at 0.8 V vs. Hg/HgO for methanol (166 mA cm-2) and urea electro-oxidations (161 mA cm-2). The methanol and urea oxidation rates of the Ni-MOF/Ti3C2-10 hybrid nanostructure are approximately five and three times higher than that of pure Ti3C2 MXene and pristine Ni-MOF, respectively. This work provides the potential of the Ni-MOF-integrated Ti3C2 MXene hybrid nanostructure as a promising electrocatalyst for MOR and UOR.