NM12.03.02 : Surface Modification of Near-Infrared I-III-VI Quantum Dots

5:00 PM–7:00 PM Apr 3, 2018 (America - Denver)

PCC North, 300 Level, Exhibit Hall C-E

Chloe Castaneda1 Nikolay Makarov1 Hunter McDaniel1 Karthik Ramasamy1

1, UbiQD, LLC, Los Alamos, New Mexico, United States

Near-Infrared (NIR) emitting fluorophores attract significant attention due to their potential use in a wide variety of applications including biolabeling, solar windows, and medical diagnostics. Currently available NIR fluorophores lack wavelength tunability, do not cover the entire NIR spectrum, cover only a small portion of the NIR, suffer from low brightness, have poor stability, low quantum yield (QY), small extinction coefficients, high self-absorption, and/or are composed of Restriction of Hazardous Substances Directive prohibited elements such as Cd, Hg, or Pb. UbiQD solves the problems of existing NIR fluorophores with I-III-VI semiconductor-based quantum dots (QDs). Moreover, these CuInSexS2-x/ZnS QDs have a tunable emission ranging from 550 nm to 1300 nm (visible-to-NIR) with QY >90% for most of that range, coupled with a large absorption cross section, and inherently large Stokes shifts. However, for these QDs to be used in almost any application, their surface must be modified for better compatibility with the host matrix or biological media. The conventional surface modification methods found in literature often create surface defects significantly reducing QY and brightness, we developed a surface modification method that allows our QDs to be soluble in different media while retaining most of their original optical properties. The results of the surface modification approach together with optical characterizations of QDs in different media will be presented.