Femtosecond laser-induced nano- and microstructuring of Cu electrodes for CO electroreduction in acetonitrile medium.

The dependency of CO reduction rate in acetonitrile-BuNClO solution on cathodes, which were modified by laser induction of a copper surface, was studied. The topography of laser-induced periodic surface structures (LIPSS) → grooves → spikes was successively formed by a certain number of pulses. It was proved that for a higher number of laser pulses, the surface area of the copper cathode increases and preferred platy orientation of the copper surface on [022] crystallografic direction and larger fluence values increase. At the same time, the content of copper (I) oxide on the surface of the copper cathode increases. Also, the tendency to larger fluency values is observed. It promotes the increase of cathodic current density for CO reduction, which reaches values of 14 mA cm for samples with spikes surface structures at E = - 3.0 V upon a stable process.