Investigation of the Emission Spectral Properties of Carbon Dots in Packaged LEDs Using TiO2 Nanoparticles

Abstract

We examined light-emitting diodes (LEDs) packaged with silicone encapsulation of carbon dots (CDs) that is doped using TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> nanoparticles (TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> NPs). The results reveal that the adjustable emission spectra in a wide wavelength range (peak wavelength varies from ~430 to ~600 nm) can be obtained by controlling the amount of TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> NPs for CDs embedded in the silicone encapsulant, and that the various colors of LEDs can be produced using CDs at a concentration of 10 wt%. Moreover, the luminous intensity can be increased by 31% at a TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> NPs concentration of 0.05 wt%. These optical characteristics of CDs-based LEDs emerge from the enhanced light scattering ability of TiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> NPs, which increases the light reabsorption and extraction probability. Therefore, the proposed method has great potential for achieving low-cost and high-performance CDs-based LEDs for particular applications.