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Office of Commercialization

Florida State University seeks partner to license:
Contact: Jack Sams - jsams@fsu.edu

A High-Efficiency Multi-junction Photovoltaic Cell for Harvesting Solar Energy

Solar energy is a renewable energy source that continues to receive increased interest worldwide as it is the most abundant source of free energy available on the planet.

At present, most of the commercially available solar cells are, at best, approximately 19% efficient in their ability to absorb energy from the sun. Increasing conversion efficiency will reduce the land acreage and support facilities needed to harvest a certain amount of energy. Improved cell design with higher efficiencies can theoretically reduce the amount of land use for solar power. However, these cells have not yet reached the market and are still in the development phase.

At the Florida State University, a novel multi-junction photovoltaic cell has been proposed by Dr. Simon Foo that will significantly increase solar energy conversion efficiency in excess of 40%, that is, more than double the efficiency of commercially-available crystalline silicon cells. The new design introduces a third layer to the solar cell that will enable the cell to absorb a wider range of the sunlight spectrum. The third layer is comprised of an Indium-Gallium-Antimonide (InGaSb) semiconductor material that improves the absorption of photons with wavelengths from near-infrared to the end of the infrared region of the solar spectrum. Importantly, of the infrared, visible light, and UV regions of the solar spectrum, it is the infrared region that contains the largest amount of harvestable energy.

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  • Aerospace
  • Building construction
  • Civil engineering
  • Electronics
  • Power stations
  • Stand-alone and grid-connected applications
  • Distributed power generation


  • More efficient than the single layer photovoltaic cells that are currently available on the market
  • More efficient than existing multi-junction solar cells that are currently under development
  • Is capable of harvesting energy of photons with wavelengths exceeding 598nm, the largest portion of the solar spectrum