Low-cost carbon nanodots could boost applications

Chinese researchers have developed a low cost way of producing luminescent carbon nanodots (CDs) with potential anti-counterfeiting applications.

CDs have been explored for a range of applications because they are chemically inert, have low toxicity and are water-soluble, which means they could potentially be used to create biocompatible, fluorescent inks and dyes.

A number of research groups have suggested that CD-based fluorescent inks could be used in anti-counterfeiting and other applications such as bioimaging, sensors and as components of LEDs, solar cells and lasers.

Their use remains experimental however as the methods used to make them are too costly and laborious to be commercially viable.

Now, the team from Shanxi University in China worked out a way to synthesise highly-stable CDs from plentiful and cheap cotton fibres - using a simple processed based on heat and microwave irradiation - that avoids the high-cost, complex and environmentally harmful techniques currently used in their production.

"The CDs have outstanding stability such that their photoluminescent intensity does not change even after ultraviolet radiation for four hours or storage for three months," they note.

The work has been published in the journal Sensors and Actuators B: Chemical (December 31, 2015).