Self aware materials and nano-sensing

The capability is developing materials that can sense, interpret and response to changes in their environment without the aid of external intervention.

The capability is developing materials that can sense, interpret and response to changes in their environment without the aid of external intervention.  A constituent development of this overall technology is nano-scale sensors and devices capable of detecting a wide range of solvent and gaseous borne chemical and biochemical species.

The challenge

Traditional sensors are widely used for monitoring changes in a particular local environment, but have limited sensitivity and selectivity, and cannot be widely distributed with a fine spatial resolution.

The key challenge for the next generation of sensors is the development of materials that can rapidly change their form or function in response to the environment, have very high sensitivity and which can be easily or routinely distributed over a very large range or embedded into other materials/structures whilst enabling monitoring extremely fine spatial resolution. This may be to promote long life or to optimize the functionality of the material for changing environments.

One way of achieving this is through the development of nano systems. The use of nano-sized materials creates many possibilities for the next generation of sensors, which can be cheap , accurate and specific to enable widespread use of sensor networks

Not only can such nano sensors allow sensory data to be acquired with finer spatial detail and greater sensitivity, but they can also be extremely cost effective. Furthermore, they can allow materials with an embedded sensing capacity to be obtained, which also have the ability to be integrated into larger monitoring and control systems.

Our response

Although the acquisition of sensor data can provide vital information, a key challenge that remains is deciding on what actions should be taken in response to this collected data.

CSIRO is developed distributed nano-sensors based on nano dot technologies and is investigating methods for these nano dots to communicate with each other or with nano-relay devices embedded in the material. In addition we are looking at how the signal from the nano-sensor can be used to trigger changes in the materials themselves.

CSIRO dot technology is based on quantum dots, carbon dots and graphene dots. These all have the property that they absorb broad band light and give of narrow band light. They can also be sensitised to detect different chemical species. By combining such dots with photo-voltaic materials versatile and economical multi-analyte sensors can be made.

Our research efforts are also focussed towards the development of reactionary sensor systems, whereby careful tailoring of the dots can enable signals to propagate to their neighbours when a change in the local environment has occurred.  This inter-dot communication can induce particles in their vicinity to take an action, whether it be continuing the propagation of this information, or undertaking their own chemical response to somehow negate the effects of this measured change in local environment.