Premium
Electrochemical Reduction of Carbon Dioxide at Gold‐Palladium Core–Shell Nanoparticles: Product Distribution versus Shell Thickness
Author(s) -
Humphrey Jo J. L.,
Plana Daniela,
Celorrio Verónica,
Sadasivan Sajanikumari,
Tooze Robert P.,
Rodríguez Paramaconi,
Fermín David J.
Publication year - 2016
Publication title -
chemcatchem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.497
H-Index - 106
eISSN - 1867-3899
pISSN - 1867-3880
DOI - 10.1002/cctc.201501260
Subject(s) - electrochemistry , palladium , shell (structure) , electrolyte , nanoparticle , hydrogen , chemistry , electrode , carbon fibers , analytical chemistry (journal) , mass spectrometry , product distribution , materials science , chemical engineering , inorganic chemistry , nanotechnology , catalysis , organic chemistry , chromatography , composite material , composite number , engineering
The electrocatalytic reduction of CO 2 at carbon‐supported Au‐Pd core–shell nanoparticles is investigated systematically as a function of the Pd shell thickness. Liquid‐ and gas‐phase products were determined by off‐line 1 H NMR spectroscopy and on‐line electrochemical mass spectrometry. Our results uncover the relationship between the nature of the products generated and the Pd shell thickness. CO and H 2 are the only products generated at 1 nm thick shells, whereas shells of 5 and 10 nm produced HCOO − , CH 4 and C 2 H 6 . The concentration of HCOO − detected in the electrolyte was dependent on the applied potential and reached a maximum Faradaic efficiency of 27 % at −0.5 V versus the reversible hydrogen electrode for 10 nm thick shells. We conclude that collisions between absorbed hydrogen at relaxed Pd lattices and strongly bound “CO‐like” intermediates promote the complete hydrogenation to C1 and C2 alkanes without the generation of other products, such as alcohols and aldehydes.