Fuel from Photons

Biological photosynthesis is the main energy source for life on Earth, but as McCusker explains in his Perspective, artificial methods for harnessing solar energy efficiently have been difficult to achieve. McCusker highlights the report by Heyduk and Nocera, who have devised a molecule that can generate molecular hydrogen photolytically from protons in homogeneous solution. A key to the success of their system lies in the clever use of the valency of the metal atoms in the catalyst.