Several critical industries – aerospace, defense, energy, and transportation – that have extreme environments require sensors to measure and monitor numerous variables under harsh conditions for human safety and the integrity of mechanical systems.
The petrochemical industry, for instance, requires monitoring of pipeline pressures at climes ranging from hot deserts to arctic cold. Several nuclear reactors operate in a temperature range of 300 – 1000 degrees Celsius, while deep geothermal wells have temperatures as high as 600 degrees Celsius.
In a new development, a team of researchers at the University of Houston has developed a new sensor that is functional in temperatures as high as 1650 degrees Fahrenheit or 900 degrees Celsius.
“Reliable, highly sensitive, and durable sensors that can withstand such extreme environments are necessary for the maintenance, efficiency, and integrity of these applications, stated the corresponding author of the research.
The study is published in the journal Advanced Functional Materials.
Earlier, the University of Houston team developed a 111-N piezoelectric pressure sensor from single-crystalline Gallium Nitride thin films for extreme environment applications. On the downside, the sensitivity of the sensor reduces at temperatures above 350 degrees Celsius, which is marginally higher than conventional transducers manufactured of lead zirconate titanate.
According to the findings of the team, the reduction in sensitivity was due to the insufficient bandgap. The team developed a sensor with aluminum nitride to test the hypothesis.
The hypothesis was proven by subjecting the sensor to temperatures of nearly 1000 degrees Celsius, which is the highest operating temperature among piezoelectric sensors, stated the first author of the article.
Meanwhile, the researchers were excited to find aluminum nitride offers a wider bandgap and a higher temperature range than Gallium Nitride. However, the technical challenges associated with the synthesis and fabrication of flexible, high-quality thin film aluminum nitride.