Ultra-sensitive and selective Hg2+ detection based on fluorescent carbon dots

• FCDs were synthesized by one-step sodium hydroxide-assisted reflux method from PEG.
• The FCDs emit blue photoluminescence and have upconversion fluorescent property.
• The FCDs show ultra-sensitive detective ability for Hg2+ ions.

Fluorescent carbon dots (FCDs) were efficiently synthesized by one-step sodium hydroxide-assisted reflux method from poly(ethylene glycol) (PEG). The obtained FCDs exhibit excellent water-solubility and high stability. Under the UV irradiation, the FCDs could emit bright blue photoluminescence, and also they were found to show excellent up-conversion fluorescence. It was further demonstrated that such FCDs can serve as effective fluorescent sensing platform for Hg2+ ions detection with ultra-sensitivity and selectivity. The sensing system achieved a limit of detection as low as 1 fM, which is much lower than all the previous reported sensing systems for Hg2+ ions detection. This FCDs sensing system has been successfully applied for the analysis of Hg2+ ions in water samples from river, lake, and tap water, showing good practical feasibility.

Fluorescent carbon dots were efficiently synthesized by one-step sodium hydroxide-assisted reflux method from PEG and demonstrated to show high selectivity toward Hg2+ ions detection.Figure optionsDownload as PowerPoint slide