Using Nanowires To Extract Excitons from a Nanocrystal Solid

作者：Dorn August^*; Strasfeld David B; Harris Daniel K; Han Hee Sun; Bawendi Moungi G

来源：ACS Nano, 2011, 5(11): 9028-9033.

DOI：10.1021/nn203227t

• nanowire
• nanocrystal
• energy transfer
• FRET
• cadmium selenide
• CdSe

Synthetic methods yielding highly uniform colloidal semiconductor nanocrystals with controlled shapes and sizes are now available for many materials. These methods have enabled geometrical control of optical properties, which are difficult or impossible to achieve in conventional bulk solids. However, incorporating nanocrystals efficiently into photodetectors remains challenging because of the low charge carrier mobilities typical of nanocrystal solids. Here we present an approach based on exciton energy transfer from CdSe/CdS core/shell nanocrystals to embedded CdSe nanowires. By combining the wide electronic tunability of nanocrystals with the excellent one-dimensional charge transport characteristics obtainable in nanowires, we are able to increase photocurrent extraction from a nanocrystal solid by 2-3 orders of magnitude. Furthermore, we correlate local device morphology with optoelectronic functionality by measuring the local photocurrent response in a scanning confocal microscope. We also discuss how nancocrystal/nanowire hybrid devices could be used in particle detector systems.

• 出版日期2011-11