Fundamental Properties in Colloidal Quantum Dots

Abstract

A multidisciplinary approach for the production and characterization of colloidal quantum dots, which show great promise for implementation in modern optoelectronic applications, is described. The approach includes the design and formation of unique core/shell structures with alloy-composed layers between the core and the shell. Such structures eliminate interfacial defects and suppress the Auger process, thus reducing the known fluorescence blinking and endowing the quantum dots with robust chemical and spectral stability. The unique design enables the generation and sustained existence of single and multiple excitons with a defined spin-polarized emission recombination. The studies described herein implement the use of single-dot magneto-optical measurements and optically detected magnetic resonance spectroscopy, for direct identification of interfacial defects and for resolving exciton fine structure. The results are of paramount importance for a fundamental understanding of optical transitions in colloidal quantum dots, with an impact on appropriate materials design for practical applications.

Spectroelectrochemistry of Quantum Dots

“…All these optoelectronic properties make QDs very useful for a number of applications in very different fields such as electroluminescent, photovoltaic, optoelectronic and electrochromic devices, light sources, light converters, photodetectors, bio‐sensing and bio‐imaging, among others …”

“…[26] All these optoelectronic properties make QDs very useful for a number of applications in very different fields such as electroluminescent, photovoltaic, optoelectronic and electrochromic devices, light sources, light converters, photodetectors, bio-sensing and bio-imaging, among others. [11,12,[30][31][32][33][34] With respect to carbon QDs, those related with graphene are highly interesting. The UV/VIS absorption spectrum of graphene QDs (GQDs) shows two main peaks, one around 230 nm assigned to π-π* transition of C sp 2 bonds and a shoulder at about 300 nm related to n-π* transitions of C=O or CÀ O bonds.…”

Quantum dot‑based fluorescent probes for targeted imaging of the EJ human bladder urothelial cancer cell line

“…In recent years, with the development of synthesis technology and surface chemical modification, the toxicity, biological compatibility and biological molecular coupling of QDs have been effectively improved (15). QD-based fluorescent probes are widely used in chemistry, biology, medicine and other fields due to their favorable optical properties and biological compatibility (16,17).…”

γ-Radiation Enhanced Luminescence of Thiol-Capped Quantum Dots in Aqueous Solution

“…Colloid semiconductor nanocrystals, which are also known as quantum dots (QDs), exhibit unique optical and optoelectronic properties due to quantum confinement effects [1]. They have attracted great attention for their wide range of applications including biological imaging, medical diagnosis, photodynamic therapy, light-emitting diodes, photovoltaic cells and display devices [2,3,4,5].…”