Technical / Research - Page 1

A team of researchers from Hong Kong Polytechnic University (PolyU) has developed sensors which can be sprayed directly onto flat or curved surfaces. The sensors, made from a hybrid of carbon black (CB), graphene, other conductive nano-scale particles, and polyvinylidene fluoride (PVDF), can be networked to extract rich real-time information on the health status of the structure being monitored.

The technology includes a sensor network with a number of the sprayed nanocomposite sensors and an ultrasound actuator to actively detect the health condition of the structure to which they are fixed. When the ultrasound actuator emits guided ultrasonic waves (GUWs), the sensors will receive and measure the waves. If damage is detected, such as a crack in the structure, propagation of GUWs will be interfered by the damage, leading to the wave scattering phenomena to be captured by the sensor network. The damage can then be characterised quantitatively and accurately.

Researchers at Lancaster University’s tech start-up Quantum Base are working on a graphene-based identity tag that can be scanned using a smartphone, to provide a possible solution to the fake goods problem that is causing worldwide financial damage on a grand scale.

The researchers, who are showcasing their work at the Royal Society’s Summer Science Exhibition, have designed a tag that can be verified by the end user using a smartphone. While other authenticity identifiers exist, like holograms, security inks and chemical or physical markers, this new system relies on graphene to make it unique. The team explains that the 2D nature of graphene means that even the tiniest imperfections, caused by the smallest of changes in the structure of an atom, can be identified. It also makes replicating the tag hard for fraudsters, if not impossible.