Dissolved Hydrogen Sensor

Aret¿ Associates proposes to develop a novel sensor using low-temperature co-fired ceramic (LTCC), thick-film technology, to measure changes of dissolved hydrogen concentration in the ocean environment. We will employ a unique layout of the classicWheatstone bridge design that uses screened-palladium metal resistors as the transducer. Palladium absorbs hydrogen gas and changes its electrical resistance in response to the absorption. The sensor has active and inactive bridge branches. Speciallyselected coatings will make the sensor impervious to resistor metallization surface changes due to wet/dry seawater cycling, and to chemical contamination. For Phase I, Aret¿ will address and resolve critical issues such as diffusion rate, sensitivity,and the effectiveness of a noise cancellation approach. We will verify these issues with modeling and breadboard development. For Phase II we will design, develop and test a small number of prototype sensors and test them with an already developed ASWarray. The primary goal for this SBIR program is the creation of a sensor that can exploit hydrogen signals in submarine wakes. If this goal is met, Aret¿ may team with an established maker of military sensors to make the technology available to the Navy.Aret¿ may also produce the sensors within its own organization, or with a subsidiary. There is a need, as is indicated by many papers in the literature, for sensors to measure hydrogen gas that results from reactions or leaks. The need is for reliable,inexpensive, simple, low-power sensors instead of large costly instrumentation such as gas chromatographs or mass spectrometers. Aret¿ believes that it has a competitive advantage given our sensor design with the novel interspersed electrode layout and theadaptive noise cancellation of temperature influences. The potential collaborators with whom discussions have begun are leaders in the gas-phase sensing area. Aret¿'s innovations may contribute to the commercially available technology.