Morphological analysis of the deposited copper electrocatalyst was performed through Scanning/Transmission Electron Microscopy using a JEOL F200 microscope operating at an accelerated voltage of 200 kV. The measured STEM resolution for the instrument is 0.136 nm. Imaging was performed in BF-STEM mode due to better resolution in liquids . Imaging was performed using a probe size of 7, coupled with a 40 mm condenser aperture, which resulted in an approximate probe current of 60 pA. The catalyst was analyzed at select experimental times to avoid beam induced damage imparted from continuous beam irradiation effects in liquid conditions . The raw images were processed with Gatan Digital Micrograph software.