Waste-based catalyst economizes hydrogen production
S. Himmelstein | June 10, 2024
A sustainable method of managing metal machining waste that also lends itself to electrolytic hydrogen production without reliance on fossil fuels is being advanced by researchers in the U.K.
The process uses metal swarf, the particles generated as debris during metal machining, to anchor platinum or cobalt atoms. An efficient catalyst is formed with reduced concentrations of these elements, translating into a lower cost means of splitting water into hydrogen and oxygen.
The nanotextured surface of the waste material, characterized by grooves and ridges, forms space to securely contain the electrocatalysts at lower mass loadings than conventionally employed. Researchers from the University of Nottingham and electrolyzer design outfit Aqsorption applied magnetron sputtering to shower platinum atoms on the swarf's surface, which subsequently cohere into nanoparticles and settle into the nanoscale grooves.
As reported in the Journal of Material Chemistry A, this treated scrap material was demonstrated to produce hydrogen from water using only a tenth of the amount of platinum loading compared to state-of-the-art commercial catalysts. A laboratory-scale alkaline water electrolyzer incorporating 28 micrograms of platinum over 1 cm2 of swarf was documented to operate with 100% efficiency and yield 0.5 liters/minute of hydrogen gas.