Scientists create first solar cell with over 100% quantum efficiency

Researchers over on the National Renewable Energy Lab have reportedly made the 1st solar cell with an external quantum efficiency over 100%. Quantum efficiency pertains to the variety of electrons-per-second flowing in a solar cell circuit, divided by the variety of photons from the energy entering. The NREL team recorded an efficiency topping out at 114 percent, by creating the 1st working multiple exciton generation (MEG) cell. Using MEG, a single high energy photon can produce a couple of electron-hole pair per absorbed photon. The additional efficiency comes from quantum dots ‘harvesting’ energy that may rather be lost as heat. The cell itself uses anti-reflection coating on a clear conductor, layered with zinc oxide, lead selenide, and gold. NREL scientist Arthur J. Nozik predicted way back to 2001 that MEG would do the job, but it’s taken in the past for the thought to jump over from theory. The hope is, in fact, that this could result in more inexpensive solar energy, fueling the transport of the longer term .

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This post is tagged: national renewable energy, national renewable energy lab, number of electrons, quantum efficiency, reflection coating, renewable energy lab