Novel Fiber Sensors for Contaminant Monitoring Applications

78095S Related to the Department of Energy (DOE) responsibility to remediate nuclear weapons sites, there is a need to characterize and monitor the soils, subsurface sediments, and ground water in order to determine various contaminant levels. In particular, new in situ technologies are urgently needed to detect, monitor, and quantify gas or liquid contaminants in DOE tanks or DOE landfills. This project seeks to address this problem by using fiber-optics-based sensors, due to their simplicity, miniature size, geometrical flexibility, and low cost. Moreover, their ruggedness enables their possible deployment in harsh environments. In Phase I, a novel cavity-enhanced absorption technique known as Integrated Cavity Output Spectroscopy (ICOS) will be employed to develop a novel fiber based sensor. The sensor will be used to record concentration measurements of multiple gases including ammonia (NH3), methane (CH4), and carbon dioxide (CO2) in DOE tanks or landfills. Ultrahigh sensitivity (an enhancement factor up to 10,000) is expected, along with increased accuracy, repeatability, and specificity in real time. Commercial Applications and Other Benefits as described by the awardee: In addition to measuring ammonia, methane, and carbon dioxide, this highly sensitive fiber sensor should be extremely well suited for measuring CO2 and CO2 isotope ratio in atmospheric research, for monitoring CO and NO in power plants and chemical plants, and as a multi-species analyzer capable of measuring a wide range of environmentally significant species including nitrogen compounds, sulfur compounds, ammonia, and dioxins.