Room temperature manufacturing photoluminescent graphene quantum dots based on MXenes

Carbide-derived graphene quantum dot (GQDs) have high potential to the photoluminescent field owing to its non-toxicity, strong light harvesting capability and large surface area. In order to cost-effectively and stably produce GQDs, lowering synthesis temperature of GQDs is one of the great candidates, but it has been still a big challenge. Herein, the photoluminescent GQDs were obtained by KOH (aq) of MXene at room temperature controlling the reaction time and concentration. This facile and costeffective method can produce GQDs/TiO2 nanoparticles which had the average particle size about 1.5 nm with minor portion of amorphous carbon. The functionalized and defects in GQDs/TiO2 crystalline nanoparticles were characterized according to fabricating conditions and photoluminescent properties were precisely detected. Although the quantum yield of fabricated GQDs/TiO2 nanoparticles is 2.06%, it could be improved by optimizing the conditions of KOH activation. It was the meaningful result using facile synthesis for GQDs/TiO2 nanoparticles at room temperature and it could encompass key factor to manufacturing quantum dots. The technique can be considered general enough to expand to various research fields such as information security, display, biocompatible multicolor cellular imaging and sensors. (C) 2020 Elsevier Ltd. All rights reserved.