Electrochemical CO reduction reaction (CORR) occurring at the electrode/electrolyte interface is sensitive to both the potential and concentration polarization. Compared to static electrolysis at a fixed potential, pulsed electrolysis with alternating anodic and cathodic potentials is an intriguing approach that not only reconstructs the surface structure, but also regulates the local pH and mass transport from the electrolyte side in the immediate vicinity of the cathode. Herein, via a combined online mass spectrometry investigation with sub-second temporal resolution and 1-dimensional diffusion profile simulations, we reveal that heightened surface CO concentration promotes CORR over H evolution for both polycrystalline Ag and Cu electrodes after anodic pulses.
View Article and Find Full Text PDFComprehending the catalyst structural evolution during the electrocatalytic process is crucial for establishing robust structure/performance correlations for future catalysts design. Herein, we interrogate the structural evolution of a promising Cu-Ag oxide catalyst precursor during electrochemical carbon monoxide reduction. By using extensive in situ and ex situ characterization techniques, we reveal that the homogenous oxide precursors undergo a transformation to a bimetallic composite consisting of small Ag nanoparticles enveloped by thin layers of amorphous Cu.
View Article and Find Full Text PDFHigh-rate production of multicarbon chemicals via the electrochemical CO reduction can be achieved by efficient CO mass transport. A key challenge for C-C coupling in high-current-density CO reduction is how to promote *CO formation and dimerization. Here, we report molecularly enhanced CO-to-*CO conversion and *CO dimerization for high-rate ethylene production.
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