Enhanced quantum dot emission for luminescent solar concentrators using plasmonic interaction

Abstract

a b s t r a c tPlasmonic excitation enhanced fluorescence of CdSe/ZnS core-shell quantum dots (QDs) in the presence of Au nanoparticles (NPs) has been studied for application in quantum dot solar concentrator (QDSC) devices. We observe that there is an optimal concentration of Au NPs that gives a maximum 53% fluorescence emission enhancement for the particular QD/Au NP composite studied. The optimal concentration depends on the coupling and spacing between neighboring QDs and Au NPs. We show the continuous transition from fluorescence enhancement to quenching, depending on Au NP concentration. The locally enhanced electromagnetic field induced by the surface plasmon resonance in the Au NPs leads to an increased excitation rate for the QDs. This is evidenced by excitation wavelength dependent fluorescence enhancement, where the locally enhanced field around the Au NPs is more pronounced close to the surface plasmon resonance (SPR) wavelength. However, at higher concentrations of Au NPs non-radiative energy transfer from the QDs to the Au NPs particles leads to a decrease of the emission, which is confirmed by detection of both a double exponential lifetime decay in, and a decrease in the lifetime of the QDs. The overall fluorescence emission enhancement depends on these competing effects; increased excitation rate and non-radiative energy transfer.

Ag colloids and arrays for plasmonic non-radiative energy transfer from quantum dots to a quantum well

“…The photoresponse following the plasmon resonance is widely observed for Ag and Au [53][54][55]. Enhanced absorption and emission of QDs using plasmonics has also been demonstrated with a view towards photovoltaics [56,57]. Therefore, in a light harvesting system the plasmonic element could potentially not only be used as a solar concentrator but could perform a second important role in enhancing ET between the QD layer and the QW.…”

Controllable photoluminescence enhancement of CdTe/CdS quantum dots thin films incorporation with Au nanoparticles

“…A stronger coupling of the plasmon resonance to the excitation wavelength resulted in a larger enhancement effect in PL. Wiederrecht GP et al also reported similar results that PL enhancement of CdSe QDs on Ag NPs film [3,18]. In addition, the absorption band of Au NPs overlapped with the emission band of QDs (Figure 1) inducing the enhanced local electric field, which might result in the increase of the emission rate of QDs.…”

“…There are two possible processes to enhance the PL emission: an increased emission rate and an increased excitation rate of the QDs, which are depended on the intensity of local electric field near metal nanoparticles (MNPs). 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].…”

Fluorescent Concentrators for Photovoltaic Applications

“…Quantum yields up to considerably more than 80% were achieved [125] for this QD type, and very recently considerably increased emissions (by max. 53%) were reached by exploiting plasmonic interaction between QDs and gold nanoparticles [126]. Using two commercial CdSe/ZnS-QD types for embedding tests including MMA/PMMA-solution, some PUR-types, a polyol, and an epoxy resin the last mentioned was found to be best suited since it resulted in the most efficient samples [73].…”