Nanoscience and Nanotechnology Commons^™

Incorporation Of Zinc In Pre-Alloyed Cuin[Zn]S2/Zns Quantum Dots, Jean Carlos Morales Orocu

Graduate Theses and Dissertations

Since the early 2000s heavy-metal-free quantum dots (QDs) such as CuInS2/ZnS have attempted to replace CdSe, their heavy-metal-containing counterparts. CuInS2/ZnS is synthesized in a two-step process that involves the fabrication of CuInS2 (CIS) nanocrystals (NCs) followed by the addition of zinc precursors. Instead of the usual core/shell architecture often exhibited by binary QDs, coating CIS QDs results in alloyed and/or partially alloyed cation-exchange (CATEX) QDs. The effect that zinc has on the properties of CIS NCs was studied by incorporating zinc during the first step of the synthesis. Different In:Cu:Zn ratios were employed in this study, maintaining a constant 4:1 …

Engineered Quantum Dots For Eva Nanocomposite Films And Tio2 Photocatalysts, Md Abdul Mumin

Electronic Thesis and Dissertation Repository

Light absorbing inorganic nanoparticles in transparent plastics such as poly(ethylene-co-vinyl acetate) (EVA) are of enormous interest in emerging solar materials, including photovoltaic (PV) modules and commercial greenhouse films. Quantum dots (QDs) have the potential to absorb UV light and selectively emit visible light. However, how to stabilize the QDs for long product life spans without "blinking" while enabling their easy integration into polymer systems is lacking. This work examines different approaches for loading mesoporous silica encapsulated QDs into EVA polymer films which can control plant growth in greenhouses or enhance PV panel efficiencies.

Highly luminescent CdS and CdS-ZnS core-shell QDs …

Synthesis And Characterization Of Cdse-Zns Core-Shell Quantum Dots For Increased Quantum Yield, Joshua James Angell

Master's Theses

Quantum dots are semiconductor nanocrystals that have tunable emission through changes in their size. Producing bright, efficient quantum dots with stable fluorescence is important for using them in applications in lighting, photovoltaics, and biological imaging. This study aimed to optimize the process for coating CdSe quantum dots (which are colloidally suspended in octadecene) with a ZnS shell through the pyrolysis of organometallic precursors to increase their fluorescence and stability. This process was optimized by determining the ZnS shell thickness between 0.53 and 5.47 monolayers and the Zn:S ratio in the precursor solution between 0.23:1 and 1.6:1 that maximized the relative …