Energy-Efficient, Room-Temperature, and Facile Synthesis of Carbon Quantum Dots from Interstitial Compound TiC for the Selective Detection of Fe(III)

The synthesis of carbon quantum dots (CQDs) from renewable resources is extensively regarded as a green approach, but this method is generally accompanied by high energy consumption and complex byproducts, which limit the large-scale production of CQDs. In this work, titanium carbide-derived CQDs (TiC-CQDs) were synthesized only by mixing titanium carbide and hydrogen peroxide (1 wt %) at room temperature. The resulting byproduct was converted to a precipitate by sodium hydroxide to purify the TiC-CQDs, and the reaction mechanism was further explored. The average lateral size of TiC-CQDs is 4.2 +/- 1.1 nm and shows excellent fluorescence properties. Moreover, in an acetic acid-sodium acetate buffer solution, the fluorescence of TiC-CQDs could be selectively quenched by a ferric ion (Fe3+) with a broad concentration range of 0.2-5 mu M and 5-60 mu M and a detection limit as low as 0.14 mu M. Due to the absence of the energy input, complex equipment, and nontoxic and harmless precursors, the novel room-temperature synthesis route of TiC-CQDs is energy-efficient, safe, green, and economical, and has great potential in industrial application.