Electro-oxidation of ammonia on electrochemically roughened platinum electrodes
By Johnston, Sam; Suryanto, Bryan H. R.; MacFarlane, Douglas R.
Published in Electrochimica Acta
2019
Abstract
With the recent advances in sustainable ammonia production, the ammonia oxidation reaction (AOR) has gained interest. In this work, we present an evaluation of the performance of electrochemically roughened platinum electrodes (PtR) for aqueous AOR. Platinum electrodes were modified using square wave voltammetry at various frequencies in 0.5 M H2SO4. Platinum electrodes modified at frequencies in excess of 1 kHz tended to develop nano-structured surfaces with corresponding increases in the proportion of the active 311 phase of platinum resulting in improved AOR activity. Of the different surface structures formed by the roughening process, trigonal nano-pyramids (TNPs) with small average cross sections of 20