Stereoassembly of ultrasmall Rh-decorated zeolite imidazolate framework-MXene heterostructures for boosted methanol oxidation reaction

Due to the diminishing energy resources and environmental pollution issues, direct methanol fuel cells (DMFCs) have gained a high profile in recent decades as a green energy generator, thereby promoting the exploitation of the cost-effective and high-performance anode catalysts for the methanol oxidation reaction. Herein, we present the rational design and controllable fabrication of ultrasmall Rh nanocrystal-decorated heterostructures from Zn-based zeolites imidazolate frameworks (ZIFs) and Ti3C2Tx MXene nanosheets (Rh/ZIF-MX) via a bottom-up stereoassembly strategy. The incorporation of ZIFs creates abundant pore channels and anchoring sites for Rh immobilization, while the presence of the Ti3C2Tx nanosheets affords strong electronic interactions with the Rh atoms and simultaneously guarantees prominent electrical conductivity. Due to this synergistic effect, the harvested Rh/ZIF-MX nanoarchitectures exhibited distinct electrocatalytic superiorities towards methanol oxidation, including a large electrochemically active surface area of 161.5 m(2) g(-1), a high mass activity of 2955.1 mA mg(-1) and exceptional long-term stability, which are evidently more competitive than those of traditional Rh catalysts directly supported on carbon black, carbon nanotubes, graphene, and MXene matrices.

Automated summary

Due to the diminishing energy resources and environmental pollution issues, direct methanol fuel cells (DMFCs) have gained a high profile in recent decades as a green energy generator. In this research, ultrasmall Rh nanocrystal-decorated heterostructures were designed and fabricated from Zn-based zeolites imidazolate frameworks (ZIFs) and Ti3C2Tx MXene nanosheets (Rh/ZIF-MX) via a bottom-up stereoassembly strategy. The resulting Rh/ZIF-MX nanoarchitectures exhibited superior electrocatalytic performance for methanol oxidation, surpassing traditional Rh catalysts directly supported on carbon materials.