Constructing Zn-based MOF-MXene nanoarchitectures to stabilize ultrafine Pt nanocrystals with enhanced methanol oxidation performance

Abstract

Although the development of direct methanol fuel cell technology is regarded as one rational option to against severe energy crises and environmental pollution, the low efficiency and considerable costs of current Pt-based anode catalysts largely impede the broad-scale commercialization. Herein, a convenient bottom-up approach is developed to the spatial construction of ultrafine Pt nanocrystals stabilized on a porous heterojunction matrix built from Zn-based metal organic frameworks and Ti3C2Tx MXene nanolamellas (Pt/ZIF-Ti3C2Tx) through the stepwise solvothermal reactions. The intercalation of metal organic frameworks produces plentiful cavities and channels for the dispersion and immobilization of small-sized Pt nanoparticles, while the incorporation of Ti3C2Tx nanosheets optimizes the Pt electronic structure and ensures a high electron conductivity. As a consequence, the as-acquired Pt/ZIF-Ti3C2Tx nanoarchitectures manifest exceptional electrocatalytic methanol oxidation abilities in terms of a large electrochemically active surface area of 110.5 m2 g−1, a high mass activity of 1900.1 mA mg−1, and preferable long-term stability, all of which are significantly superior to those of conventional Pt/carbon and Pt/unmodified Ti3C2Tx catalysts.