tailieunhanh - Báo cáo hóa học: " Quantum dots coordinated with conjugated organic ligands: new nanomaterials with novel photophysics"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Quantum dots coordinated with conjugated organic ligands: new nanomaterials with novel photophysics | Nanoscale Res Lett 2007 2 282-290 DOI s11671-007-9062-8 NANO REVIEW Quantum dots coordinated with conjugated organic ligands new nanomaterials with novel photophysics Nathan I. Hammer Todd Emrick Michael D. Barnes Received 27 April 2007 Accepted 8 May 2007 Published online 6 June 2007 to the authors 2007 Abstract CdSe quantum dots functionalized with oligo- phenylene vinylene OPV ligands CdSe-OPV nanostructures represent a new class of composite nanomaterials with significantly modified photophysics relative to bulk blends or isolated components. Singlemolecule spectroscopy on these species have revealed novel photophysics such as enhanced energy transfer spectral stability and strongly modified excited state lifetimes and blinking statistics. Here we review the role of ligands in quantum dot applications and summarize some of our recent efforts probing energy and charge transfer in hybrid CdSe-OPV composite nanostructures. Keywords Single molecule spectroscopy Hybrid nanomaterial Quantum dot Blinking Conjugated polymer Energy transfer Charge transfer Photovoltaic Atomic force microscope Introduction Over the past several years semiconductor nanocrystals quantum dots have attracted enormous interest in virtually all areas of the physical sciences. The tunable optical N. I. Hammer El M. D. Barnes Department of Chemistry University of Massachusetts Amherst MA 01003 USA e-mail nhammer@ M. D. Barnes e-mail mdbarnes@ T. Emrick Department of Polymer Science and Engineering University of Massachusetts Amherst MA 01003 USA e-mail tsemrick@ and electronic properties of quantum dots make them ideal building blocks in nanoscale photonic photovoltaic and light-emitting diode LED device applications 1-19 . In addition their robust photoluminescence makes them attractive for probing dynamics in biological systems at the single molecule level 20-23 . One of the keys to the successful use of quantum dots in any application is the