PEDOT-embellished Ti3C2Tx nanosheet supported Pt-Pd bimetallic nanoparticles as efficient and stable methanol oxidation electrocatalysts

Exploiting high-efficiency and durable electrocatalysts toward the methanol oxidation reaction (MOR) is crucial for the advancement of direct methanol fuel cells (DMFCs). Herein, we demonstrate the loading of platinum-palladium bimetallic nanoparticles (Pt-Pd NPs) onto poly(3,4-ethylenedioxythiophene) (PEDOT)-embellished titanium carbide (Ti(3)C(2)Tx) nanosheets as the electrocatalyst (Ti(3)C(2)Tx/PEDOT/Pt-Pd) via a facile and rapid chemical reduction-assisted one-pot hydrothermal process. The structural and morphological analyses of Ti(3)C(2)Tx/PEDOT/Pt-Pd indicate that the three-dimensional (3D) hybrid structure formed between PEDOT and Ti(3)C(2)Tx provides a sizable active surface and more active sites, which enhances the homogeneous dispersion of the Pt-Pd NPs and facilitates mass transfer. The Schottky junctions formed between PEDOT and Pt-Pd NPs contribute to charge transfer. The electronic effects and synergistic interactions between the support and catalyst favor the electrocatalytic activity of the catalyst. The electrochemical test results reveal that the Ti(3)C(2)Tx/PEDOT/Pt-Pd catalyst has prominent electrocatalytic capability for the MOR. Compared with Ti(3)C(2)Tx/Pt-Pd and commercial Pt/C catalysts, the Ti(3)C(2)Tx/PEDOT/Pt-Pd catalyst has a larger electrochemical activity surface area (ECSA = 122 m(2) g(-1)) and higher mass activity (MA = 1445.4 mA mg(-1)), as well as better CO tolerance and more reliable long-term durability (a peak current density retention of 71% after 5200 s).

Automated summary

In this study, platinum-palladium bimetallic nanoparticles were successfully loaded onto poly(3,4-ethylenedioxythiophene) (PEDOT)-embellished titanium carbide nanosheets through a facile and rapid chemical reduction-assisted one-pot hydrothermal process. The resulting Ti(3)C(2)Tx/PEDOT/Pt-Pd catalyst demonstrated excellent electrocatalytic activity for the methanol oxidation reaction (MOR), with a larger electrochemical activity surface area and higher mass activity compared to other catalysts. The hybrid structure formed between PEDOT and Ti(3)C(2)Tx provided a sizable active surface and more active sites, enhancing the dispersion of Pt-Pd NPs and facilitating mass transfer. The Schottky junctions between PEDOT and Pt-Pd NPs contributed to charge transfer, while the electronic effects and synergistic interactions between the support and catalyst favored the catalytic activity.