Three-Dimensional MXene-Based Pd/Ni/Cu Electrocatalyst for Methanol Oxidation Reaction with Efficient Performance

Abstract

In this work, we introduce a unique approach for fabricating a three-dimensional (3D) Cu-ZIF-8/MXene, combing the merits of MOFs and MXene to enhance their overall performance. Subsequently, the synthesis of 3D MXene-based Cu and N-doped porous carbon (Cu-NPCM) composites, characterized by high specific surface area, superior conductivity, and abundant active sites, was achieved through the carbonization and acid etching of Cu-ZIF-8/MXene. Utilizing the resulting 3D Cu-NPCM composites as effective electrocatalyst supports, Ni and Pd NPs were uniformly dispersed, preventing the aggregation of metal NPs. The unique structure of Cu-NPCM, coupled with the synergy of Ni and Pd, facilitates the creation of interconnected channels for rapid reactant and product diffusion, along with a substantial amount of OHad, thereby enhancing the electrocatalytic efficiency. Remarkably, the designed trimetallic Pd/Ni/Cu-NPCM catalyst demonstrates an advanced mass activity of 3641.2 mA mgPd –1 in the methanol oxidation reaction (MOR), surpassing Pd/Cu-NPCM (2200.5 mA mgPd –1), Pd/Cu-NPC (1447.1 mA mgPd –1), and Pd/C (209.3 mA mgPd –1) electrocatalysts by 1.66, 2.51, and 17.4 times, respectively. This research introduces an innovative approach to creating advanced support materials for electrocatalysts, simultaneously expanding the range of potential applications for direct methanol fuel cells (DMFCs).