{"170581":{"#nid":"170581","#data":{"type":"event","title":"Prof. Colin D. Heyes, University of Arkansas","body":[{"value":"\u003Cp\u003EProf. Colin D. Heyes, University of Arkansas\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003E\u003Cem\u003ETuning Organic-Inorganic and Inorganic-Inorganic Interfaces of Quantum Dots for Ensemble and Single Molecule Fluorescence Applications\u003C\/em\u003E\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EPhysical Chemistry Seminar Series\u003C\/p\u003E\u003Cp\u003EDue to the high surface-to-volume ratio of nanoparticles, the fluorescence properties of colloidal quantum dots (QDs) are strongly affected by the various interfaces present. Simple core-only QDs have an inorganic-organic surface-ligand interface, while core-shell (or core-multishell) quantum dots have, in addition, inorganic-inorganic core-shell interfaces. We have systematically tuned the interfaces of cadmium-chalcogenide or copper-indium-chalcogenide cores and upon adding cadmium- and zinc-chalcogenide shells. The optical and structural properties at the ensemble and single particle level are analyzed by a combination of time-resolved fluorescence spectroscopy, single-particle fluorescence microscopy, quantitative FT-IR absorption spectroscopy, X-ray photoelectron (XPS) spectroscopy and high-resolution TEM\/HAADF-STEM\/EELS microscopy. In particular, we explore connections between the structural details of the interfaces and the quantum yield, radiative and non-radiative excited state decay rates, ligand binding, fluorescence blinking and the formation of a dark fraction. We also evaluate the response of these properties to external environments will be discussed to help devise strategies to tailor QDs for various applications. To illustrate these connections, I will present several applications utilizing bandgap and lifetime engineering of quantum dots \u2013 in particular for ultrasensitive biophysical and biomedical imaging.\u003C\/p\u003E\u003Cp\u003E\u003Ca href=\u0022http:\/\/chemistry.uark.edu\/4871.php\u0022\u003EProf. Heyes\u0027 web page\u003C\/a\u003E\u003C\/p\u003E\u003Cp\u003EFor more information contact \u003Ca href=\u0022mailto:angelo.bongiorno@chemistry.gatech.edu\u0022\u003EProf. Angelo Bongiorno\u003C\/a\u003E (404-385-5169).\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"\u003Cp\u003EProf. Colin D. Heyes, University of Arkansas\u003C\/p\u003E\u003Cp\u003E\u003Cstrong\u003E\u003Cem\u003ETuning Organic-Inorganic and Inorganic-Inorganic Interfaces of Quantum Dots for Ensemble and Single Molecule Fluorescence Applications\u003C\/em\u003E\u003C\/strong\u003E\u003C\/p\u003E\u003Cp\u003EPhysical Chemistry Seminar Series\u003C\/p\u003E","format":"limited_html"}],"field_summary_sentence":[{"value":"Prof. Colin D. Heyes, University of Arkansas"}],"uid":"27275","created_gmt":"2012-11-12 14:23:15","changed_gmt":"2016-10-08 02:01:17","author":"Shirley Tomes","boilerplate_text":"","field_publication":"","field_article_url":"","field_event_time":{"event_time_start":"2013-01-24T15:00:00-05:00","event_time_end":"2013-01-24T16:00:00-05:00","event_time_end_last":"2013-01-24T16:00:00-05:00","gmt_time_start":"2013-01-24 20:00:00","gmt_time_end":"2013-01-24 21:00:00","gmt_time_end_last":"2013-01-24 21:00:00","rrule":null,"timezone":"America\/New_York"},"extras":[],"groups":[{"id":"85951","name":"School of Chemistry and Biochemistry"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[{"id":"1795","name":"Seminar\/Lecture\/Colloquium"}],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cp\u003EShirley Tomes (404-894-0591) \u003Ca href=\u0022mailto:shirley.tomes@chemistry.gatech.edu\u0022\u003Eshirley.tomes@chemistry.gatech.edu\u003C\/a\u003E\u003C\/p\u003E","format":"limited_html"}],"email":[],"slides":[],"orientation":[],"userdata":""}}}