Using the energy in sunlight together with water and air to make fuel—artificial photosynthesis—is a little closer thanks to an advance involving nanoscale crystals known as quantum dots.

 

Researchers have been working on artificial photosynthesis for many years (see “Sun + Water = Fuel”). One approach involves using particles that combine light-absorbing materials with catalysts that can split water. But the light-absorbing materials tend to deteriorate quickly in sunlight, rendering the approach impractical.

 

In the latest issue of the journal Science, researchers from the University of Rochester show that quantum dots not only absorb the light but also are far more durable than previous light-absorbing materials. The new approach also has the advantage of not requiring any precious metals, so it might be relatively cheap.

 

The new approach doesn’t solve all of the challenges with artificial photosynthesis. The proof-of-concept system developed by the Rochester team does only half of the water-splitting reaction—that is, it makes hydrogen, but not oxygen.