Multiple Exciton Generation in Semiconductor Nanocrystals: Toward Efficient Solar Energy Conversion

Journal Article · Tue Jan 01 04:00:00 EST 2008 · Laser and Photonics Reviews

DOI:https://doi.org/10.1002/lpor.200810013· OSTI ID:950131

Beard, M C; Ellingson, R J

Within the range of photon energies illuminating the Earth's surface, absorption of a photon by a conventional photovoltaic semiconductor device results in the production of a single electron-hole pair; energy of a photon in excess of the semiconductor's bandgap is efficiently converted to heat through interactions between the electron and hole with the crystal lattice. Recently, colloidal semiconductor nanocrystals and nanocrystal films have been shown to exhibit efficient multiple electron-hole pair generation from a single photon with energy greater than twice the effective band gap. This multiple carrier pair process, referred to as multiple exciton generation (MEG), represents one route to reducing the thermal loss in semiconductor solar cells and may lead to the development of low cost, high efficiency solar energy devices. We review the current experimental and theoretical understanding of MEG, and provide views to the near-term future for both fundamental research and the development of working devices which exploit MEG.

• Research Organization: National Renewable Energy Laboratory (NREL), Golden, CO.
• Sponsoring Organization: USDOE
• DOE Contract Number: AC36-99GO10337
• OSTI ID: 950131
• Journal Information: Laser and Photonics Reviews, Journal Name: Laser and Photonics Reviews Journal Issue: 5, 2008 Vol. 2
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
36 MATERIALS SCIENCE
77 NANOSCIENCE AND NANOTECHNOLOGY
ABSORPTION
CRYSTAL LATTICES
EFFICIENCY
ELECTRONS
EXCITONS
Materials Science and Semiconductors
PHOTONS
PRODUCTION
SEMICONDUCTOR DEVICES
SOLAR CELLS
SOLAR ENERGY
SOLAR ENERGY CONVERSION