Photogeneration and recombination of multiexcitons in nanocrystal quantum dots in relation to solar energy conversion

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

A usual assumption is that absorption of a single photon by a material produces a single electron-hole pair (exciton), while the photon energy in excess of the energy gap is dissipated as heat. In 2004, we reported for the first time that nanocrystals of PbSe could respond to absorption of a single photon by producing two or more excitons with the unity probability (Phys. Rev. Lett. 92, 186601, 2004). More recently, we observed generation of up to seven excitons per absorbed photon (Nano Lett. 6, 424, 2006), which corresponds to the ultimate limit allowed by energy conservation for the excitation energy used in these measurements. This presentation discusses such aspects of multi-exciton generation in nanocrystals as characteristic time scales of this process, statistics of photogenerated multiexciton populations, the limits on photon-to-exciton conversion efficiencies, and implications of multiexciton generation in photovoltaics and photocatalysis.

Original languageEnglish
Title of host publicationACS National Meeting Book of Abstracts
Publication statusPublished - 2007
Event233rd ACS National Meeting - Chicago, IL, United States
Duration: Mar 25 2007Mar 29 2007

Other

Other233rd ACS National Meeting
CountryUnited States
CityChicago, IL
Period3/25/073/29/07

Fingerprint

Energy conversion
Nanocrystals
Solar energy
Semiconductor quantum dots
Photons
Excitation energy
Photocatalysis
Conversion efficiency
Energy conservation
Energy gap
LDS 751
Statistics
Electrons

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Photogeneration and recombination of multiexcitons in nanocrystal quantum dots in relation to solar energy conversion. / Klimov, Victor I.

ACS National Meeting Book of Abstracts. 2007.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Klimov, VI 2007, Photogeneration and recombination of multiexcitons in nanocrystal quantum dots in relation to solar energy conversion. in ACS National Meeting Book of Abstracts. 233rd ACS National Meeting, Chicago, IL, United States, 3/25/07.
@inproceedings{06ff6e6d8a28447ea2b26f6edefcfb95,
title = "Photogeneration and recombination of multiexcitons in nanocrystal quantum dots in relation to solar energy conversion",
abstract = "A usual assumption is that absorption of a single photon by a material produces a single electron-hole pair (exciton), while the photon energy in excess of the energy gap is dissipated as heat. In 2004, we reported for the first time that nanocrystals of PbSe could respond to absorption of a single photon by producing two or more excitons with the unity probability (Phys. Rev. Lett. 92, 186601, 2004). More recently, we observed generation of up to seven excitons per absorbed photon (Nano Lett. 6, 424, 2006), which corresponds to the ultimate limit allowed by energy conservation for the excitation energy used in these measurements. This presentation discusses such aspects of multi-exciton generation in nanocrystals as characteristic time scales of this process, statistics of photogenerated multiexciton populations, the limits on photon-to-exciton conversion efficiencies, and implications of multiexciton generation in photovoltaics and photocatalysis.",
author = "Klimov, {Victor I}",
year = "2007",
language = "English",
isbn = "084127438X",
booktitle = "ACS National Meeting Book of Abstracts",

}

TY - GEN

T1 - Photogeneration and recombination of multiexcitons in nanocrystal quantum dots in relation to solar energy conversion

AU - Klimov, Victor I

PY - 2007

Y1 - 2007

N2 - A usual assumption is that absorption of a single photon by a material produces a single electron-hole pair (exciton), while the photon energy in excess of the energy gap is dissipated as heat. In 2004, we reported for the first time that nanocrystals of PbSe could respond to absorption of a single photon by producing two or more excitons with the unity probability (Phys. Rev. Lett. 92, 186601, 2004). More recently, we observed generation of up to seven excitons per absorbed photon (Nano Lett. 6, 424, 2006), which corresponds to the ultimate limit allowed by energy conservation for the excitation energy used in these measurements. This presentation discusses such aspects of multi-exciton generation in nanocrystals as characteristic time scales of this process, statistics of photogenerated multiexciton populations, the limits on photon-to-exciton conversion efficiencies, and implications of multiexciton generation in photovoltaics and photocatalysis.

AB - A usual assumption is that absorption of a single photon by a material produces a single electron-hole pair (exciton), while the photon energy in excess of the energy gap is dissipated as heat. In 2004, we reported for the first time that nanocrystals of PbSe could respond to absorption of a single photon by producing two or more excitons with the unity probability (Phys. Rev. Lett. 92, 186601, 2004). More recently, we observed generation of up to seven excitons per absorbed photon (Nano Lett. 6, 424, 2006), which corresponds to the ultimate limit allowed by energy conservation for the excitation energy used in these measurements. This presentation discusses such aspects of multi-exciton generation in nanocrystals as characteristic time scales of this process, statistics of photogenerated multiexciton populations, the limits on photon-to-exciton conversion efficiencies, and implications of multiexciton generation in photovoltaics and photocatalysis.

UR - http://www.scopus.com/inward/record.url?scp=37349063405&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=37349063405&partnerID=8YFLogxK

M3 - Conference contribution

SN - 084127438X

SN - 9780841274389

BT - ACS National Meeting Book of Abstracts

ER -