Investigation into the fluorescence quenching behaviors and applications of carbon dots

Abstract

Carbon dots (CDs) are novel fluorescent materials with low toxicity and good biocompatibility. Herein, the collisional/dynamic and photoluminescence (PL) center destruction quenching behaviors of a novel type of CDs were investigated. Moreover, the quenching behaviors of the CDs were exploited in applications. Firstly, dynamic PL quenching was achieved by Fe(3+) ions, which was proved by the Stern-Volmer equation, temperature dependent quenching and fluorescence lifetime measurements. Furthermore, a hemin sensor based on the Fe(3+)/CDs system was achieved. Secondly, quenching induced by PL center destruction was caused by hydroxyl radicals (˙OH), which were produced by high power UV light or the H2O2/Fe(2+) system; thus an H2O2 sensor with a low detection limit (0.9 ppb) was realized. Finally, we assumed that the CDs are really composed of cross-linked molecular clusters, and that the PL centers of the as prepared CDs are certain molecular/chemical groups.

Development of hydrophilicity gradient ultracentrifugation method for photoluminescence investigation of separated non-sedimental carbon dots

“…2(b)), and further confirms their polymer-like nature. The QYs of f1 and f5 both exceed 0.45, implying the high brightness of the polymer-like species under UV irradiation, which agrees with previous reports [28].…”

Production of yellow-emitting carbon quantum dots from fullerene carbon soot

“…The emission wavelength first moves to higher values when the pH is increased from 2 to 8, then decreases with a further increase in the pH. Similar trend has also been reported previously [23,24,45,[54][55][56], which could be caused by the change of surface charge density induced by the protonation-deprotonation processes.…”

Carbon Based Dots and Their Luminescent Properties and Analytical Applications

“…In general, the detection mechanisms are similar to those mentioned above. [240]. However, they proposed different mechanisms (Fig.…”

“…31 a Fe 3+ and H 2 O 2 sensors based on visual fluorescent detection were achieved, utilizing a special kind of CDs. The origin of the PL of these CDs may be their molecular state, and the PL can be quenched through electron transfer or PL center destruction [240]. b Sensing Principle of the N-Doped C-Dots based probe for Fe 3+ (upper figure) and PL microscopy images of Hela cells first incubated with N-CDs for 6 h and then incubated with FeCl 3 (lower figure) [91].…”