Fig. 2: Current distribution in an ePTFE electrode strongly depends on catalyst thickness.

a Infrared thermography setup for an electrochemical flow cell. b Space-dependent temperature increase on an ePTFE/1000 nm Cu electrode (left), an ePTFE/500 nm Cu electrode (center), and an ePTFE/50 nm Cu electrode (right) at –50 mA cm–2. c Space-dependent temperature increase on the same electrodes at –200 mA cm–2. d Impact of catalyst-layer thickness on the product selectivity of ePTFE electrodes at increasing current densities.