A catalyst is a substance that speeds up a chemical reaction without being consumed itself. The best catalyst is one where every metal atom counts: the finer the particles, the more atoms are on the surface and the more active the material. Scientists have long dreamed of anchoring single metal atoms on a support, but doing so uniformly and in large quantities has been challenging.
This new method resembles sandblasting, but instead of sand, it uses a stream of metal ions. The support is bombarded with ions, which slam into the surface and get stuck one by one. By controlling the energy and number of ions, uniform dispersion of single atoms can be achieved. This allowed the team to assemble 36 different catalysts and test their performance.
This approach paves the way for cheap, mass production of efficient catalysts for hydrogen production, air purification, and other important processes.
Platinum is one of the most expensive metals, but the new catalyst needs hundreds of times less of it than conventional ones because every atom works.
The idea of controlling matter at the level of individual atoms echoes the nanotechnology of science fiction novels, where machines assemble materials atom by atom.