- feldspars, aluminosilicate from mining waste may be combined with selected, expensive metals, e.g., Pt ($1450/oz), Ir ($1370/oz) and Ru ($367/oz) or cheaper Co ($70,000/t), Ni ($26,000/t) and Fe ($641/t) to form effective 'water splitting' catalysts
https://phys.org/news/2021-09-ingredient-cheaper-hydrogen-fuel-production.htmlWater splitting reactions that produce hydrogen are triggered using rare platinum ($1450/ounce), iridium ($1370/ounce) and ruthenium ($367/ounce), or cheaper but less active metals—cobalt ($70,000/ton), nickel ($26,000/ton) and iron ($641/ton).
Professor Ziqi Sun from the QUT School of Chemistry and Physics and QUT Centre for Materials Science and Dr. Hong Peng from the School of Chemical Engineering at the University of Queensland led research to create a new catalyst using only a small amount of these reactive metals.
They combined them with feldspars, aluminosilicate rock minerals found in mining waste that Professor Sun said some companies pay about $30/ton to dispose of.
In the experiment, featured on the August cover of Advanced Energy & Sustainability Research, the researchers triggered a water splitting reaction using heated-activated feldspars nanocoated with only 1–2 percent of the cheaper reactive metals.
"Water splitting involves two chemical reactions—one with the hydrogen atom and one with the oxygen atom—to cause them to separate," Professor Sun said.
"This new nanocoated material triggered the oxygen evolution reaction, which controls the overall efficiency of the whole water splitting process," he said.
Professor Sun said cobalt-coated feldspar was most efficient and optimizing the new catalysts could see them outperform raw metals or even match the superior efficiency of platinum metals.