Enabling methanol oxidation by an interacting hybrid nanosystem of spinel Co₃O₄ nanoparticle decorated MXenes

For the successful implementation of direct methanol fuel cells in commercial applications, highly efficient and durable non-noble electrocatalysts based on conducting and stable non-carbonaceous supports can be potential candidates. Herein, spinel Co₃O₄ nanoparticles are decorated over Ti₃C₂ MXene nanosheets for methanol oxidation. The hybrid nanosystem Ti₃C₂/Co₃O₄ (TC) reduces restacking of MXene nanosheets, which offers a larger surface area for Co₃O₄ dispersion, leading to a shorter path for the charge carriers. TC coated on glassy carbon (GC) exhibits a MOR current density of 38.38 A g^-1 which is 2.9 times higher than that of Co₃O₄/GC in 1.5 M methanol at a 20 mV s^-1 scan rate. The hydrophilic terminations on the surface of MXenes create strong interactions with the Co₃O₄ nanoparticles, which increase the MOR kinetics of the nanocomposite. A low onset potential (0.32 V), high oxidation current density of the nanocomposite, efficient durability and cycling stability up to 200 CV cycles make this nanocomposite a better alternative to the state-of-the-art noble-metal electrocatalysts.