Femtosecond laser-induced nano- and microstructuring of Cu electrodes for CO2 electroreduction in acetonitrile medium

The dependency of CO2 reduction rate in acetonitrile-Bu4NClO4 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 CO2 reduction, which reaches values of 14 mA cm(-2) for samples with spikes surface structures at E = - 3.0 V upon a stable process.

Automated summary

The study investigates the effect of laser-induced copper surface modification on the CO2 reduction rate in acetonitrile-Bu4NClO4 solution. By using a certain number of laser pulses, laser-induced periodic surface structures (LIPSS) consisting of grooves and spikes are formed. It is found that a higher number of laser pulses leads to a larger surface area of the copper cathode, a preferred platy orientation of the copper surface on [022] crystallographic direction, and an increased content of copper (I) oxide on the surface. Moreover, a tendency towards larger fluence values is observed, which promotes the increase in cathodic current density for CO2 reduction.