Solar energy: Springtime for the artificial leaf
On a bright spring morning in Pasadena, California, the air is rich with the smells of cut grass and flowers. Photosynthesis seems effortless here: the fronds and blooms that line the walkways of the California Institute of Technology (Caltech) bask in the sunlight, quietly using its energy to store sugars, stretch their leaves, deepen their roots and tend to their cellular processes.
Inside Caltech’s Jorgensen Laboratory, however, more than 80 researchers are putting a lot of effort into doing the leaf’s job using silicon, nickel, iron and any number of other materials that would be more at home inside a cell phone than a plant cell. Their gleaming new labs are the headquarters of the Joint Center for Artificial Photosynthesis (JCAP), a 190-person research programme funded by the US Department of Energy (DOE) with US$116 million over five years. The centre’s goal is to use sunlight to make hydrogen and other fuels much more efficiently than real leaves ever made biomass.