NASA STTR 2005 Solicitation


RESEARCH SUBTOPIC TITLE:Batteryless, Wireless Remote Sensors
PROPOSAL TITLE:Passive Wireless Hydrogen Sensors Using Orthogonal Frequency Coded Acoustic Wave Devices

NAME: Applied Sensor Research & Development Corporation NAME:University of Central Florida
ADDRESS:Unit 2, 1195 Baltimore-Annapolis Blvd ADDRESS:4000 Central Florida Boulevard
CITY:Arnold CITY:Orlando
STATE/ZIP:MD  21012-1808 STATE/ZIP:FL  32816-8005
PHONE: (410) 544-4664 PHONE: (407) 823-2414

Jacqueline   Hines

TECHNICAL ABSTRACT ( Limit 2000 characters, approximately 200 words)
This proposal describes the continued development of passive orthogonal frequency coded (OFC) surface acoustic wave (SAW) based hydrogen sensors for NASA application to distributed wireless hydrogen leak detection systems. These novel sensors use an OFC SAW device structure, combined with Palladium (Pd) nanocluster film elements and hydrophobic self assembled monolayer (SAM) coatings to produce fast, reversible, highly sensitive hydrogen sensors capable of detecting a wide range of hydrogen concentrations at room temperature. The technical feasibility of these sensors was clearly demonstrated in Phase I. The Pd films experience conductivity changes due to the hydrogen induced stretching of the Pd nanoclusters and the quantum nature of conduction in nanocluster films. The performance of the SAW device will change in response to a change in conductivity of this film. Rapid (under 1 second) room temperature detection of hydrogen was observed, with complete reversibility of response. Compatibility of film conductivity with acoustic wave propagation and detection of changes in film conductivity using variations on SAW device delay were confirmed. Manufacturing compatible processes for SAM deposition and patterning were developed. The successful elimination of the potential technical risks accomplished in this Phase I effort provides a sound basis for further development of these sensors.

POTENTIAL NASA COMMERCIAL APPLICATIONS ( Limit 1500 characters, approximately 150 words)
The primary NASA application for the proposed sensors would be in a wireless multisensor system for hydrogen leak detection. With uniquely identifiable sensors, such a system could use low cost sensors mounted at numerous locations to remotely detect hydrogen leaks in real time. This system could continuously monitor "boot" air for leaks, and remotely alert personnel and/or trip alarms or initiate protective action if a leak is detected. The extreme sensitivity of these films to low levels of hydrogen, and their ability to operate reversibly without baseline drift at room temperature, should provide an advanced warning capability for leaks.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS ( Limit 1500 characters, approximately 150 words)
The commercial market for the proposed hydrogen sensors is extremely promising. Sensors will be needed for hydrogen leak detection in hydrogen storage, transport, and distributed hydrogen forming facilities, and for residential and automotive fuel cell applications. Use of hydrogen as a fuel for automotive and fleet vehicles is already emerging. Major automotive manufacturers see residential and industrial fuel cell use as a means to increase production volumes and lower costs. The high sensitivity, fast response times, reversibility, wide range of hydrogen concentration sensed, low cost, and small size would make the proposed sensors applicable to these emerging market segments.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Fluid Storage and Handling
Propellant Storage
Sensor Webs/Distributed Sensors

Form Printed on 01-23-07 12:19