Sensors for Measuring Subsurface and Ambient Nitrogen Oxides (NOx and N2O) from Agricultural Production Systems

Two major anthropogenic events need immediate attention. First is climate change triggered byincreased emission of greenhouse gases (GHG) including carbon dioxide (CO ) nitrous oxide2 (N O) and methane (CH ). The second is increased air pollution from particulate matter (PM2.5)2 4 and ozone catalyzed by nitrogen oxides NO (NO =NO+NO ). Agricultural practices play a majorx x 2 role in exacerbating both problems. Fertilizers based on ammonium compounds and nitrates areessential for growing crops that feed humanity but their use leads to the formation and release ofN O and NO . In this SBIR project RedNOx an Ohio State University (OSU) start-up and2 x scientists and engineers from OSU will develop inexpensive N O and NO sensors that can be2 x deployed for both subsurface and ambient gas measurements. Sensors for N2O will utilize near- infrared spectroscopy and sensors for NO are based on solid-state electrochemical sensors. Thesex technologies have been demonstrated for making ppm and ppb measurements of ambient N O and2 NOrespectively. Phase I of the SBIR program will primarily focus on soil subsurfacex measurements a more difficult challenge and involve appropriate packaging of the sensorsincluding minimizing interferences and size of sensor and power electronics. Demonstration ofsensor performance under fertilization practices will be done at a research farm at OSU. Phase IIwill involve miniaturization developing wireless data transfer capability and promoting fieldconnectivity. Wide availability of N O and NO sensors will facilitate proper use of fertilizers2 x minimize GHG and polluting gases and provide farmers with means to avail of carbon credits.