An international team of scientists have made a breakthrough discovery by realizing why nanoporous gold (NPG) has a high catalytic activity and can be used for making fuel cells and durable catalytic converters, as opposed to bulk gold, which is inert.
The team, comprising of Dr. Keith McKenna, from the University of York and other colleagues from Japan, China and the U.S., created nanoporous gold by immersing an alloy of gold and silver in a chemical solution that dissolved the silver and left a porous gold structure with silver leftovers.
They then used transmission electron microscopy to outline the surface defects of the gold and established that they were responsible for the high catalytic properties of it. The residual silver made up for increased stability of the entire structure.
Finding better catalysts for hydrogen fuel cells is essential to the hydrogen economy envisioned by green technology evangelists. However, a cheap but good catalyst (besides the expensive platinum) still has to be found. The scientists behind this discovery are hoping that by explaining how these materials work, they will provide an important clue for future research.