Detection and imaging of reactive oxygen species associated with the electrochemical oxygen evolution by hydrodynamic scanning electrochemical microscopy

Hydrodynamic scanning electrochemical microscopy (SECM) was applied for the characterization of Pt and boron-doped diamond (BDD) macroelectrodes operated in a potential region producing reactive oxygen species (ROS) during oxygen evolution reaction (OER). Forced convection introduced by high-precision stirring enabled the formation of a stable diffusion layer of electrochemically produced species and tip-substrate voltammetry was used for the detection of different ROS species produced during OER at BDD. Hydrodynamic SECM imaging in substrate generation/tip collection mode revealed local differences in the production of the ROS species across the BDD electrode surface.