High resolution imaging analysis of CdSe/ZnS core–shell quantum dots (QDs) using Cs-corrected HR-TEM/STEM

Autor: Kyuho Park, M. J. Cho, Youngil Jang, Dongseon Jang, Hui-Youn Shin
Rok vydání: 2013
Předmět:
Zdroj: Journal of Materials Science: Materials in Electronics. 24:3744-3748
ISSN: 1573-482X
0957-4522
Popis: CdSe/ZnS core–shell structured nano-crystal quantum dots (QDs) are ideal candidates for light-emission applications due to their high quantum efficiency, narrow-band, and particle-size-tunable photoluminescence. In particular, their small size results in the quantum confinement of semiconductor nano-crystals, which widens their energy gaps. In general, high resolution imaging analyses of QDs using a transmission electron microscope are very difficult due to their significantly small size. Successful imaging depends on the capabilities of TEM equipment and the contrast of the QDs sample relative to the supporting film. In this work, all imaging analyses were performed on a TEM equipped with a probe Cs corrector. The samples for observing QDs were prepared by drying each QDs solution on a lacey carbon Cu (300 mesh) grid previously coated with an ultra-thin graphene monolayer (thickness = 0.3 nm), due to the need to minimize the effect of the supported film.
Databáze: OpenAIRE