Near-infrared enhanced carbon nanodots by thermally assisted growth

The near-infrared emission, matching the biological window, is conducive to biological applications. To date, most of the reported carbon nanodots emit the blue to green fluorescence and few of carbon nanodots emit the near-infrared with relatively lower efficiency. Here, we report an approach to generate or to enhance the near-infrared luminescence from the green luminescent carbon nanodots. Experiments reveal that the near-infrared emission is significantly enhanced by thermally assisted growth in vacuum, which is attributed to the formation of the larger nano-domains from the small carbon clusters at elevated temperatures. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4760275]