Recently, graphene quantum dots (GQDs) with polychrome emission capability have attracted much attention due to their multifarious applications. In this study, we report a facile and green approach for rapid preparation of multicolor emission GQDs. Experimentally, UV light was used to drive the lowtemperature synthesis, and a tunable emission wavelength of the GQDs was achieved through the synergistic effect of solvatochromic tuning and sulfur doping. Results show that multicolor emission wavelengths of green-GQDs (G-GQDs) from blue to yellow are obtained by simply controlling the polarity of the surrounding solutions. Moreover, red-GQDs with the emission wavelengths extended from green to red are further obtained by sulfur doping. Thereafter, G-GQDs were used to develop a trace water-detecting platform, ascribed to the high sensitivity of water-quenchable fluorescence, and a low detection limit of 0.061% was achieved. Meanwhile, based on the outstanding multicolor tunability of as-prepared GQDs, we successfully manufactured multicolor solid fluorescence films to fabricate multicolor light-emitting diode (LED) devices. Furthermore, high-quality white LEDs (WLEDs) are fabricated with the CIE coordinates of (0.341, 0.354) and a color temperature of 5161 K. This study highlights the potential of GQDs in various applications, including solid-state fluorescence films, optoelectronics, and optical molecular sensing.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.