A palladium solution for hydrogen leaks
2011 R&D 100 Winner
Heated or electrically probed transducers in hydrogen leak sensors can increase the risk of heat-induced explosions, making them unsuitable for safety devices. The Hydrogen safety sensor based on nanostructured palladium cantilevers developed by Oak Ridge National Laboratory, Oak Ridge, Tenn., and the University of Tennessee, Knoxville, provides an alternate approach for sensing hydrogen leaks. The sensor responds to the presence of hydrogen gas in environments with varying temperature (0 to 30 C) and humidity, as well as gas species that interfere with the operation of most other palladium-based sensors.
The sensor contains palladium nanoparticles, small fractions of palladium oxide, and other additives, which together exhibit rapid and reversible volumetric responses in the presence of hydrogen gas. These responses impart hydrogen sensitivity and selectivity to a silicon nitride cantilever-based nanomechanical transducer. The high surface area nanostructured palladium film forms high oxide content under environmental conditions (concentration range of 0.1 to 100 V/V%) that facilitates rapid responses and interferent immunity. Volumetric responses are converted into deflections of the cantilever transducer, and the amount of cantilever bending can be read using optical probing. No electrical interrogation of the sensing elements in contact with the hydrogen-containing medium is required, eliminating the possibility of heat-induced or spark-induced explosions.
Hydrogen safety sensor
|(Back row, l-r): James Patton, Scott Hunter, Nickolay Lavrik, Michael Sepaniak
(l-r): Panos Datskos, Barton Smith
The Hydrogen safety sensor based on nanostructured palladium cantilevers Development Team
Nickolay Lavrik, Prinicpal Developer, Center for Nanophase Materials Sciences, Oak Ridge National Laboratory
Panos Datskos, Oak Ridge National Laboratory Measurement Science and Systems Engineering Division
Scott Hunter, Oak Ridge National Laboratory Measurement Science and Systems Engineering Division
James Patton, University of Tennessee at Knoxville
Michael Sepaniak, University of Tennessee at Knoxville
Barton Smith, Oak Ridge National Laboratory Measurement Science and Systems Engineering Division