1D-2D hybridization: Nanoarchitectonics for grain boundary-rich platinum nanowires coupled with MXene nanosheets as efficient methanol oxidation electrocatalysts

Although a direct methanol fuel cell with high energy utilization efficiency and low hazardous emission has broad application prospects in various energy-related fields, the insufficient methanol oxidation activity as well as the short service life of the anode catalysts continue to hinder its large-scale commercialization. Herein, we demonstrate a convenient and robust approach for the controllable synthesis of 1D grain boundary-rich Pt nanowires strongly coupled with ultrathin Ti3C2Tx MXene nanosheets (Pt NWs/MX). Such a unique architectural design endows the heterojunction catalysts with a series of structural merits, including large accessible surface area, stable interconnected Pt networks, numerous grain boundary sites, ameliorative electronic structure, and excellent electron conductivity. Consequently, the optimized Pt NWs/MX catalyst exhibits a unique methanol oxidation performance with a large electrochemically active surface area of 105.5 m2 g-1, a high mass (specific) activity of 1621.5 mA mg-1 (1.6 mA cm-2), as well as superior long-term durability, making it more competitive than conventional Pt nanoparticle/carbon catalysts with the same Pt loading.

Automated summary

Researchers have successfully synthesized a heterojunction catalyst of Pt nanowires and MXene nanosheets with high methanol oxidation performance and long-term durability. The catalyst possesses structural advantages such as large accessible surface area, stable interconnected Pt networks, and numerous grain boundary sites. It exhibits higher activity and competitiveness compared to traditional Pt nanoparticle/carbon catalysts.