Ultrafast Carrier Dynamics in Type II ZnSe/CdS/ZnSe Nanobarbells

Autor:	Patrick Z. El-Khoury, Maria Kirsanova, Alexander N. Tarnovsky, Alexander Nemchinov, Ian Nemitz, Mikhail Zamkov, Nishshanka N. Hewa-Kasakarage
Rok vydání:	2010
Předmět:	Materials science business.industry General Engineering General Physics and Astronomy Electron Marcus theory Nanocrystal Excited state Femtosecond Ultrafast laser spectroscopy Optoelectronics General Materials Science Nanorod Spectroscopy business
Zdroj:	ACS Nano. 4:1837-1844
ISSN:	1936-086X 1936-0851
DOI:	10.1021/nn100229x
Popis:	We employ femtosecond transient absorption spectroscopy to get an insight into ultrafast processes occurring at the interface of type II ZnSe/CdS heterostructured nanocrystals fabricated via colloidal routes and comprising a barbell-like arrangement of ZnSe tips and CdS nanorods. Our study shows that resonant excitation of ZnSe tips results in an unprecedently fast transfer of excited electrons into CdS domains of nanobarbells (0.35 ps), whereas selective pumping of CdS components leads to a relatively slow injection of photoinduced holes into ZnSe tips (tau(h)= 95 ps). A qualitative thermodynamic description of observed electron processes within the classical limit of Marcus theory was used to identify a specific charge transfer regime associated with the ultrafast electron injection into CdS. Potential photocatalytic applications of the observed fast separation of carriers along the main axis of ZnSe/CdS barbells are discussed.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::446ff4e938206bab3733586374ea930f https://doi.org/10.1021/nn100229x Zobrazit plný text záznamu