Strain and Shell Thickness Engineering in Pd₃Pb@Pt Bifunctional Electrocatalyst for Ethanol Upgrading Coupled with Hydrogen Production

Abstract

The ethanol oxidation reaction (EOR) is an attractive alternative to the sluggish oxygen evolution reaction in electrochemical hydrogen evolution cells. However, the development of high‐performance bifunctional electrocatalysts for both EOR and hydrogen evolution reaction (HER) is a major challenge. Herein, the synthesis of Pd3Pb@Pt core–shell nanocubes with controlled shell thickness by Pt‐seeded epitaxial growth on intermetallic Pd3Pb cores is reported. The lattice mismatch between the Pd3Pb core and the Pt shell leads to the expansion of the Pt lattice. The synergistic effects between the tensile strain and the core–shell structures result in excellent electrocatalytic performance of Pd3Pb@Pt catalysts for both EOR and HER. In particular, Pd3Pb@Pt with three Pt atomic layers shows a mass activity of 8.60 A mg−1Pd+Pt for ethanol upgrading to acetic acid and close to 100% of Faradic efficiency for HER. An EOR/HER electrolysis system is assembled using Pd3Pb@Pt for both the anode and cathode, and it is shown that low cell voltage of 0.75 V is required to reach a current density of 10 mA cm−2. The present work offers a promising strategy for the development of bifunctional catalysts for hybrid electrocatalytic reactions and beyond.

Photochemical engineering unsaturated Pt islands on supported Pd nanocrystals for a robust pH-universal hydrogen evolution reaction

“…[11][12][13] Welldesigned core-shell structures can not only facilitate the modulation of the electronic structure of catalysts to optimize H* adsorption behavior but also increase the number of exposed active sites, thereby enhancing the intrinsic catalytic activity. [14][15][16] For instance, Zhang et al reported various Pd@Ir core-shell nanostructures with well-defined fcc-2H-fcc heterophases which exhibit excellent catalytic performance toward HER. The modified electronic structures of Ir in the fcc-2H-fcc heterophases can provide large amounts of high-index facets, step sites and uncoordinated atoms on the surface of the nanodendrites, providing abundant active sites and optimizing the adsorption energy towards the intermediate H* to improve the HER performance.…”

Electrocatalytic Oxidation of Benzaldehyde on Gold Nanoparticles Supported on Titanium Dioxide

“…Under an applied voltage of only ~0.1 V, both the cathode and anode can simultaneously generate H 2 [ 17 ]. We have also demonstrated the viability of the oxidation of other small molecules such as ethanol, methanol, urea, formate, and ethylene glycol [ 18 , 19 ].…”