Artificial leaf looks set to flourish

The advance, reported in Nature Chemistry, has been made by BISfuel, a US Department of Energy funded Energy Frontier Research Center in the Department of Chemistry and Biochemistry at Arizona State University(ASU).

‘Initially, our artificial leaf did not work very well, and our diagnostic studies on why indicated that a step where a fast chemical reaction had to interact with a slow chemical reaction was not efficient,’ said ASU chemistry professor Thomas Moore in a statement. ‘The fast one is the step where light energy is converted to chemical energy, and the slow one is the step where the chemical energy is used to convert water into its elements viz. hydrogen and oxygen.’

The researchers took a closer look at how nature had overcome a related problem in the part of the photosynthetic process where water is oxidised to yield oxygen.

‘We looked in detail and found that nature had used an intermediate step,’ said Moore. ‘This intermediate step involved a relay for electrons in which one half of the relay interacted with the fast step in an optimal way to satisfy it, and the other half of the relay then had time to do the slow step of water oxidation in an efficient way.’