Chemical reactions are at the centre of modern industry, from converting wastewater to hydrogen fuel through to turning vegetable oils into margarine. Catalysts make these chemical reactions faster and more energy efficient. New single atom catalysts act faster and are more energy efficient than traditional catalysts, making them an exciting prospect. However, their adoption has been hindered by the complexity and cost of production.
Now, an international team led by Prof. Shizhang Qiao at the University of Adelaide, has developed a simple, low-cost technique for 3D-printing single-atom catalysts. These catalysts are made up of many individual metal atoms dispersed in a scaffold, creating space between the atoms to allow maximum reaction efficiency. Prof. Qiao’s team found they could use a 3D bioprinter with cheap and readily available materials to print a polymer scaffold with the metal atoms embedded within it.
Atomic scale microscopy and elemental mapping at our University of Adelaide facility, along with X-ray spectroscopy at the Australian Synchrotron, were used to confirm the even dispersal of metal atoms within the polymer.
To test the printing system, the team printed a single atom catalyst designed to convert nitrates in wastewater into ammonia – the world’s most important fertiliser and one of the most energy intensive industrial chemical processes. Excitingly, this test demonstrated highly efficient ammonia production.
Moving forward, the team are exploring the potential of 3D-printed single-atom catalysts for other critical chemical reactions used in industry. They hope to make these catalysts technically and economically viable within ten years.
F. Xie et al., Nature Synthesis 2023
September 21, 2023