September 2016

A team of scientists at Columbia University has discovered the possibility of greatly boosting the efficiency of hybrid organic inorganic perovskite (HOIP) solar cells.

The team showed how HOIPs have a far lower rate of energy loss than silicon cells, making it possible for the harvesting of excess electronic energy to increase the efficiency of solar cells. The recent Columbia study has actually found that it's possible to make HOIP-based solar cells even more efficient than anyone thought possible.

Researchers at Saudi Arabia's King Abdullah University of Science and Technology (KAUST) have shown how imploding bubbles in a solution can grow single crystals of perovskites especially suited for solar applications.

The researchers explain that hybrid perovskite materials can easily be fabricated on a large scale from a solvent solution. However, this process typically produces polycrystalline perovskite films that have a smaller solar light conversion efficiency than monocrystalline materials because the boundary between crystalline grains leads to losses. In particular, growth of single-crystalline perovskite solar cell films has not yet been achieved on top of other materials, which is a requirement for practical devices.

Researchers at the Energy Department's National Renewable Energy Laboratory (NREL) discovered a use for perovskites that could push forward the development of quantum computing.

The discovery, made quite accidentally, occurred while the researchers were investigating excitons in perovskites. The sample was illuminated with a short laser pulse whose wavelength was specifically tuned to avoid being absorbed by the sample. Instead, the exposure triggered a strong interaction of light with the perovskite, producing a shifted transition energy known as the optical Stark effect. The effect occurs in semiconductors, but typically can only be observed at extremely low temperatures in very high-quality, high-cost materials. NREL's scientists were able to observe the effect quite readily at room temperature in materials grown using solution processing.