This paper, written by researchers from Sichuan Key Laboratory of Chemical Synthesis and Pollution Control and others, discusses Microwave-assisted rapid green synthesis of photoluminescent carbon nanodots from flour and their applications for sensitive and selective detection of mercury(II) ions. The paper is published in an important journal < Sensors and Actuators B: Chemical >. IF：5.667.

In recent years, the research work of microwave chemical instrument used in the synthesis of materials has become a hot direction of scientific research, which has been paid great attention to by many scholars!

The article reports on the microwave-assisted rapid green synthesis of photoluminescent carbon nanodots (C-dots) with diameters in the range of 1–4 nm using flour as the carbon source. It suggests that the resultant C-dots exhibit high sensitivity and selectivity toward Hg2+ with a detection limit as low as 0.5 nM and a linear range of 0.0005–0.01 M. The practical use of this system for Hg2+ determination in real lake water samples is also demonstrated successfully.

In summary, microwave irradiation of an aqueous dispersion of flour has been proven to be a facile method for rapid green synthesis of C-dots. Such C-dots can serve as an effective fluorescent sensing probe for sensitive and selective detection of Hg2+ with a detection limit as low as 0.5 nM. Our observations are important because it provides us a rapid, low cost route toward green production of C-dots for sensing, bioimaging and optical imaging and other applications [2–5].

C-dots were prepared as follows: In a typical synthesis, 80 mg of flour was sealed and heated in a computer-controlled XH-800C microwave digestion system (Beijing XiangHu Science and Technology Development Co. Ltd.) at 180 ◦C for a period of 20 min. The precipitate was discarded and the supernatant was submitted to centrifugation at 14,000 rpm for 10 min. The pellet was dried under vacuum for 48 h and re-dispersed in distilled water at a concentration of 2 mg/mL for further characterization and use.