Scottish university develops ‘record-braking’ temperature sensor

A University of Glasgow-led team has designed a smart skin sensor able to detect temperatures above 200°C. 

Up to now, similar sensors had to rely on multiple thermistors to measure temperature variation, meaning the breakthrough could make wireless technology cheaper and more sustainable. 

With the technology’s global market value standing at $5-8bn, the cutting-edge device has the potential to bring significant economic opportunities. 

Mahmoud Wagih, who led the study said: “Sensors are the main interface between the analogue world and smart devices. To communicate real-world changes in measurements like temperature or humidity to wireless smart devices, those measurements first need to be digitised. 

“Many researchers have used RF (radio frequency) and microwave devices to measure liquid formulations, temperature, humidity, and other physical and chemical parameters. However, this level of sensitivity has not been demonstrated before.” 

The innovative technology can detect a range from 30°C to more than 200°C and can sustain impacts to its framework without losing its sensitivity. 

It is made of a composite of carbon fibres and silicon rubber and works without battery power or onboard processing.  

Engineers partnered with fellow researchers from the University of Southampton to design the flexible material and the University of Loughborough to analyse the material’s electrical properties. The latter suggested anisotropic properties could enhance or reduce sensitivity to specific wireless signals. 

Other contributors included colleagues from the manufacturing firm PragmatIC Semiconductor Ltd in Cambridge. 

During testing, researchers used a 3D printer to mould the material and integrate it into other components, including antennas and resonators, before testing its capability to absorb RF radiation at temperatures up to 300°C.  

It is thought the technology could eventually underpin the design of vital sign monitoring, radar sensing, satellite communications, and 6G wireless networks.  

The next stage of the research, funded by the UK Engineering and Physical Sciences Research Council, will investigate new applications in sustainable and biodegradable wireless electronics. 

The team’s research paper, titled ‘Wide-range soft anisotropic thermistor with a direct wireless radio frequency interface’, has been published in the scientific journal Nature Communications.