Credit: Image adapted by permission from Macmillan Publishers Ltd: Nature Materials, ©2015
Nanoplates of a close relative of fool’s gold, a pyrite-type cobalt phosphosulfide (CoPS) catalyst (left), enhanced the light-harvesting properties of a photoelectrochemical cell that used the solar energy to produce hydrogen by splitting apart water. Films integrated into the cell (right) created an efficient solar-to-hydrogen cell using Earth-abundant cobalt rather than rare and expensive metals.