Data from: Cu+ transient species mediate Cu catalyst reconstruction during CO2 electroreduction

<p>Understanding metal surface reconstruction is of the uttermost importance in heterogeneous<br> catalysis as this phenomenon directly affects the nature of available active sites. However,<br> surface reconstruction is notoriously difficult to study because of the dynamic nature of the<br> phenomena behind it, particularly when solid/liquid interfaces are involved. Here, we report<br> on the intermediates which drive the rearrangement of copper catalysts for the electrochemical<br> CO2 reduction reaction (CO2RR). Online mass spectrometry and UV-Vis absorption<br> spectroscopy data are consistent with a dissolution&ndash;redeposition process, previously<br> demonstrated by in-situ electron microscopy. The data indicate that the soluble transient<br> species contain copper in +1 oxidation state. Density functional theory identifies copper adsorbate<br> complexes which can exist in solution under operating conditions. Copper carbonyls and oxalates are suggested as the major reaction-specific species driving copper reconstruction&nbsp;during CO2RR. This work motivates future methodological studies to enable the direct&nbsp;detection of these compounds and strategies which specifically target them to improve the&nbsp;catalyst operational stability.</p>