Abstract
Au nanoparticles (Au NPs)/CdTe/CdS QDs nanocomposite films were fabricated by deposition of Au NPs and layer-by-layer self-assembly of colloidal CdTe/CdS QDs. Photoluminescence (PL) spectra showed that Au NPs incorporation resulted in an increase of PL intensity about 16-fold compared with that of the samples without Au NPs. PL enhancement of Au NPs/CdTe/CdS QDs nanocomposite films can be controlled by tuning the thickness of spacer layer between the metal nanoparticles (MNPs) and QDs. Optical absorption spectra exhibited the incorporation of Au NPs boosted the absorption of Au NPs/CdTe/CdS QDs nanocomposite films. The results of finite-difference time-domain (FDTD) simulation indicated that the increased sizes of Au NPs resulted in stronger localization of electric field, which boosted the PL intensity of QDs in the vicinity of Au NPs. We thought that these were mainly attributed to localized SP enhancement effects of the Au NPs. Our experiment results demonstrated that Au NPs/QDs nanocomposite films would be a promising candidate for optoelectronic devices application.PACS78.55.-m; 82.33.Ln; 68.65.Hb
Highlights
Semiconductor quantum dots (QDs) have been attracted much attention on the application of solid-state lighting and photovoltaics due to the unique optical properties
The surface plasmon (SP) absorption band of Au nanoparticles (Au NPs) overlaps with the absorption and emission spectra of QDs, which might lead to an enhanced local electric field
The maximum absorbance was obtained when the spacer layer was six poly(diallyldimethylammonium chloride) (PDDA)/poly(sodium 4-styrenesulfonate) (PSS) bilayers. These results indicated that Au NPs incorporation boosted the absorption of QDs
Summary
Semiconductor quantum dots (QDs) have been attracted much attention on the application of solid-state lighting and photovoltaics due to the unique optical properties. The use of QDs in such applications needs the investigation of obtaining highly efficient QDs. Recently, an effective approach by using the interaction of surface plasmon (SP) with QDs has been raised to enhance the photoluminescence (PL) emission of QDs [1,2]. The overall effect of SP at work is determined by the competition between emission enhancement, excitation enhancement, and quenching [3]. Some research groups have demonstrated the application of MNPs in optoelectronic devices based on the SP resonance effects [4,5,6,7]. The effect of the size of MNPs and the thickness of spacer layer between MNPs and QDs on the plasmonic interaction has rarely been demonstrated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
