Genetically Modified Virus To Boost Efficiency Of Solar Cells - MIT

Nature's photosynthesis beats artificial solar cells hands down when it comes to efficiency. Photosynthesis, a phenomenon perfected by nature since the beginning of the life on Earth achieves near perfect efficiency in transporting the light energy from the Sun to the reaction centers in the plants where it's converted into life supporting units. Engineers at MIT have figured out a way to mimic this to achieve significant gain in the solar cell efficiency.

Researchers at MIT and Eni, an energy company from Italy used genetically modified viruses to make this happen. The work was published in a recent issue of journal 'Nature Materials'.


Seth Lloyd, one of the researchers and a professor of mechanical engineering explains the process. During photosynthesis, photon, which is basic unit of light hits the receptor on the plant leaves, called 'chromophore' and produces an 'exciton'. The exciton is a quantum particle of energy that jumps between chromophores to reach to the reaction center where it's harnessed.

The hopping path taken by excitons, however is not the shortest unless they make use of the quantum effects to select the best one. The efficient transfer of excitons require that the chromophores are arranged correctly with just the right gap between them. Lloyd says that this is known as Quantum Goldilocks Effect.

MIT researchers figured out a way to to bond genetically engineered viruses to bond with multiple synthetic chromophores or organic dyes. They produced several varieties of the virus with various spacings between the chromophores and pick up only the ones that worked the best.


The end result was that the team could improve the speed of excitons by almost 200% and increase the overall distance they traveled before dissipating. The team used laser spectroscopy and dynamical modeling to witness the entire light harvesting process. They also demonstrated that the genetically transformed viruses were actually using quantum coherence to improve the overall transportation of excitons.

The initial results of the laboratory experiements act as a 'proof of concept' providing a direction to the researchers to work on a practical system. Further exploration holds the potential to creation of economical and highly efficient solar cells.

Source: Quantum physics meets genetic engineering | MIT News | Massachusetts Institute of Technology