PbSe has an exciton Bohr radius of 46 nm, which allows the exploitation of quantum confinement effects to tune electronic and optical properties for applications including solar cells, solid-state lighting, flat-panel displays, photodetectors, etc. The synthesis of PbSe colloidal quantum dots (QDs) provides excellent control of these properties by controlling the PbSe diameter and composition. Gamma radiation detection and spectroscopy are new applications for PbSe QDs. Currently the industry standard for gamma ray spectroscopy is high-purity germanium semiconductor diode detectors, however these must be operated at liquid nitrogen temperatures and are expensive. In this presentation, we will show results on the synthesis and characterization of PbSe QDs, and their integration into devices for gamma radiation detection and spectroscopy. We have developed a microwave assisted procedure for the synthesis of PbSe QDs. The method is reproducible, where we are able to produce spherical PbSe QDs from 4-8 nm in diameter by controlling reaction time and temperature. The PbSe QDs are characterized by transmission electron microscopy, energy dispersive X-ray spectroscopy, UV-Vis-NIR spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. We then fabricate gamma ray detectors with the PbSe QDs. These devices are electronically characterized, and their response to gamma radiation is monitored. Optimal device structure and PbSe QD properties will be reported for gamma ray detection and spectroscopy.

Application of colloidal PbSe quantum dots for room temperature gamma ray spectroscopy

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.