In the latest issue of the International Journal of Global Energy Issues, researchers report of an experimental device that use sunlight to convert glucose into hydrogen to power the cell, which produces several hundred millivolts.

The researchers have built the device with a transparent conductive glass electrode coated with a highly colored molecule that can mimic the natural process of photosynthesis. This molecule is incorporated into light-absorbing titania. The coating can absorb energy from sunlight and release it into another chemical layer on the electrode. This is connected to a platinum electrode and the pair is immersed in a glucose solution to complete the circuit.

When light shines on the light-active electrode enzymes in the chemical layer are triggered to react with glucose molecules in the solution and release hydrogen ions, the dissolved hydrogen ions then attract electrons from the platinum electrode, which causes a current to flow through the wire connecting the electrodes.

Source: EurekAlert