Glycerol-Bonded 3C-SiC Nanocrystal Solid Films Exhibiting Broad and Stable Violet to Blue-Green Emission

Abstract

We have produced glycerol-bonded 3C-SiC nanocrystal (NC) films, which when excited by photons of different wavelengths, produce strong and tunable violet to blue-green (360-540 nm) emission as a result of the quantum confinement effects rendered by the 3C-SiC NCs. The emission is so intense that the emission spots are visible to the naked eyes. The light emission is very stable and even after storing in air for more than six months, no intensity degradation can be observed. X-ray photoelectron spectroscopy and absorption fine structure measurements indicate that the Si-terminated NC surfaces are completely bonded to glycerol molecules. Calculations of geometry optimization and electron structures based on the density functional theory for 3C-SiC NCs with attached glycerol molecules show that these molecules are bonded on the NCs causing strong surface structural change, while the isolated levels in the conduction band of the bare 3C-SiC NCs are replaced with quasi-continuous bands that provide continuous tunability of the emitted light by changing the frequencies of exciting laser. As an application, we demonstrate the potential of using 3C-SiC NCs to fabricate full-color emitting solid films by incorporating porous silicon.

Fabrication and Characterization of Beaded SiC Quantum Rings with Anomalous Red Spectral Shift

“…There have already been reports that the surface structure (e.g., reconstruction or termination) of SiC NCs will influence their optical properties. [35] For example, SiC NCs with hydrogen and hydroxy bonding exhibit quite different optical properties, where a new peak at 510 nm emerges when the surface of SiC NCs is functionalized by H + and OH − . [35] …”

“…[35] For example, SiC NCs with hydrogen and hydroxy bonding exhibit quite different optical properties, where a new peak at 510 nm emerges when the surface of SiC NCs is functionalized by H + and OH − . [35] …”

“…However, these surface passivations (–CH 3 and –OR) are unlikely to lead to the anomalous red spectral shift according to previous studies. [35] …”

UV-blue photoluminescence from close-packed SiC nanocrystal film

“…[1][2][3][4] SiC is an outstanding wide-bandgap semiconductor for applications in high power, high temperature, and high frequency electronic devices owing to its superior physical and mechanical properties. The peak wavelength shifts from blue to near UV with increasing excitation energy and follows well the quantum-confinement effect.…”

Facile synthesis, microstructure and photophysical properties of core-shell nanostructured (SiCN)/BN nanocomposites

“…In particular, SiC and BN semiconductor nanocrystals have enabled and transformed research in technologically important areas including biolabeling789, microelectromechanical (MEMS) and optoelectronic devices101112. For example, emission wavelengths can now be precisely controlled by the nanostructure composition, the average grain size and the formation of core-shell structures4131415.…”