title: Selenium Redox Reactivity on Colloidal CdSe Quantum Dot Surfaces.
abstract: Understanding the structural and compositional origins of midgap states in semiconductor nanocrystals is a longstanding challenge in nanoscience. Here, we report a broad variety of reagents useful for photochemical reduction of colloidal CdSe quantum dots, and we establish that these reactions proceed via a dark surface prereduction step prior to photoexcitation. Mechanistic studies relying on the specific properties of various reductants lead to the proposal that this surface prereduction occurs at oxidized surface selenium sites. These results demonstrate the use of small-molecule inorganic chemistries to control the physical properties of colloidal QDs and provide microscopic insights into the identities and reactivities of their localized surface species.
authors: Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States.
authors: Emily Y
authors: EY
authors: Tsui
authors: Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States.
authors: Kimberly H
authors: KH
authors: Hartstein
authors: Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States.
authors: Daniel R
authors: DR
authors: Gamelin
mesh_terms: D000478:Alkylation; D019187:Cadmium Compounds / Q000737:chemistry*; D003102:Colloids; D010084:Oxidation-Reduction; D045663:Quantum Dots / Q000737:chemistry*; D012643:Selenium / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D019187:Cadmium Compounds; D003102:Colloids; D018036:Selenium Compounds; C058667:cadmium selenide; D012643:Selenium