Semiconducting Nanocrystal Opto-Electronics
My Master’s work was devoted to synthesis, photophysical characterization, and device fabrication using quantum dots and nanocrystals. This work was the perfect way to kick off my research career in nanoscience, where I learned a wide range of skills from chemistry to femtosecond spectroscopy, electron microscopy, and device engineering. I specially thanks my Master’s advisor, Prof. Mikhail Zamkov and the Zamkov Lab!
Schematic of lead sulfide quantum dot sensitized solar cell
Nanocrystal Solar Cell: PbS on TiO2
One potential use of quantum dots is for the development of third generation solar cells technologies. Here we made advances in QD sensitized solar cells by growing lead sulfide quantum dots epitaxially on porous titanium dioxide thin films.
Transmission electron micrograph of lead sulfide/cadmium sulfide core/shell quantum dots.
Nanocrystal Solar Cell: PbS/CdS core/shell
In this study, we employed our laboratory's matrix encapsulation method to fabricate highly stable nanocrystal solar cells with a customizable band-gap for the tunability of photon absorption and nanoscale control of inter-particle distance.
Image of a flask containing fluorescent zinc selenide/cadmium sulfide dot-in-a-rod nanocrystals.
Nanocomposite photocatalyst: ZnSe/CdS/Pt
More complex nanocrystal composites can be used in photocatalysis to split water into hydrogen and oxygen using sunlight! These studies were the topic of my Master’s thesis, and lead to a number of deep photophysics publications including proof of concept, ultrafast charge carrier dynamics at the femtosecond time scale, and nanocrystal optimization to improve catalytic performance using the knowledge gained in the first two studies!
Image of a light emitting film comprising an inorganic matrix of cadmium selenide/cadmium sulfide core/shell quantum dots.
Nanocrystal light emitting films: CdSe/CdS core/shell
Core/shell quantum dots provide size tunable luminescence with high quantum efficiency. Particles were assembled into a chemically stable, inorganic matrix through the SMENA technique. Quantum does such as these are being developed into next generation displays because of their color customization, amenability to low cost, high throughput printability, and excellent color gamut range.