title: Electronic and surface properties of PbS nanoparticles exhibiting efficient multiple exciton generation.
abstract: Ultrafast transient absorption measurements have been used to study multiple exciton generation in solutions of PbS nanoparticles vigorously stirred to avoid the effects of photocharging. The threshold and slope efficiency of multiple exciton generation are found to be 2.5 ± 0.2 ×E(g) and 0.34 ± 0.08, respectively. Photoemission measurements as a function of nanoparticle size and ageing show that the position of the valence band maximum is pinned by surface effects, and that a thick layer of surface oxide is rapidly formed at the nanoparticle surfaces on exposure to air.
authors: School of Physics and Astronomy and the Photon Science Institute, University of Manchester, Oxford Road, Manchester M13 9PL, UK. samantha.hardman@manchester.ac.uk
authors: Samantha J O
authors: SJ
authors: Hardman
authors: Darren M
authors: DM
authors: Graham
authors: Stuart K
authors: SK
authors: Stubbs
authors: Ben F
authors: BF
authors: Spencer
authors: Elaine A
authors: EA
authors: Seddon
authors: Ho-Ting
authors: HT
authors: Fung
authors: Sandra
authors: S
authors: Gardonio
authors: Fausto
authors: F
authors: Sirotti
authors: Mathieu G
authors: MG
authors: Silly
authors: Javeed
authors: J
authors: Akhtar
authors: Paul
authors: P
authors: O'Brien
authors: David J
authors: DJ
authors: Binks
authors: Wendy R
authors: WR
authors: Flavell