Lattice-Strained Metallic Aerogels as Efficient and Anti-Poisoning Electrocatalysts for Oxygen Reduction Reaction

Lattice strain engineering optimizes the interaction between the catalytic surface and adsorbed molecules. This is done by adjusting the electron and geometric structure of the metal site to achieve high electrochemical performance, but, to date, it has been rarely reported on anti-poisoned oxygen reduction reaction (ORR). Herein, lattice-strained Pd@PdBiCo quasi core-shell metallic aerogels (MAs) were designed by one-pot and two-step method for anti-poisoned ORR. Pd@PdBiCo MAs/C maintain their original activity (1.034 A mgPd-1) in electrolytes with CH3OH and CO at 0.85 V vs. reversible hydrogen electrode (RHE), outperforming the commercial Pd/C (0.156 A mgPd-1), Pd MAs/C (0.351 A mgPd-1), and PdBiCo MAs/C (0.227 A mgPd-1). Moreover, Pd@PdBiCo MAs/C also show high stability and anti-poisoning with negligible activity decay after 8000 cycles in 0.1 m KOH+0.3 m CH3OH. These results of X-ray photoelectron spectroscopy, CO stripping, and diffuses reflectance FTIR spectroscopy reveal that the tensile strain and strong interaction between different elements of Pd@PdBiCo MAs/C effectively optimize the electronic structure to promote O2 adsorption and activation, while suppressing CH3OH oxidation and CO adsorption, leading to high ORR activity and anti-poisoning property. This work inspires the rational design of MAs in fuel cells and beyond. Lattice-strained Pd@PdBiCo quasi core-shell metallic aerogels (MAs) are designed for anti-poisoned oxygen reduction via one-pot and two-step method. Pd@PdBiCo MAs/C exhibit a high mass activity of 1.034 A mgPd-1 at 0.85 VRHE even in poisoned environment, 6.6 times higher than that of the commercial Pd/C. This work provides a new idea for the design and application of high-performance MAs.image

Automated summary

Lattice-strained Pd@PdBiCo quasi core-shell metallic aerogels (MAs) are designed for anti-poisoned oxygen reduction via one-pot and two-step method. Pd@PdBiCo MAs/C exhibit a high mass activity of 1.034 A mgPd-1 at 0.85 VRHE even in poisoned environment, 6.6 times higher than that of the commercial Pd/C. This work provides a new idea for the design and application of high-performance MAs.