Prof. Shi-Woo Rhee Improves Coloration of Carbon Nanodots Using Surface Functionalization
Carbon nanodots (C-dots) are a new class of fluorescent carbon nanomaterials that have excellent biocompatibility and photostability. They have numerous properties including strong UV absorption and blue-to-green photoluminescence, and have been recently used as an imaging agent in biomedical systems or as a phosphor in light-emitting devices.
Prof. Shi-Woo Rhee’s (Dept. of Chemical Engineering) research team has chemically modified the surface of C-dots via surface functionalization to control their photoluminescence. This new development shows that surface functional groups play a major role in the photoluminescence of C-dots, providing important information about its origin. Prof. Rhee’s research also expands the practicality of C-dots to be used for bioimaging, photovoltaics, and optoelectronics. The team’s research was published in Scientific Reports.
The surface functionalization gives the C-dots new energy levels and long-wavelength photoluminescence of very narrow spectral widths. The team also used C-dots as a phosphor, converting UV light to a variety of colors including green, yellow, orange, and red light of high color purity.
The research was supported by the Samsung Research Funding Center of Samsung Electronics.
(a) Photographs of light-converting films. (b) Structure of LEDs. (c) Emission spectra of LEDs. (d) Photographs of LEDs during operation.