Chemiresistive Sensors for Effective Agricultural Nitrogen Management and Nitrous Oxide Mitigation

The long-term objective of this research is to develop new N₂O sensing technologies that operate with low power requirements, which can be distributed in the field through the soil profile to give real-time quantification of N₂O production, consumption, and emissions. At the heart of the envisioned sensing device is a molecular recognition element, known as a “selector”, that can translate a chemical interaction with N₂O at the sensor surface into a measurable electrical signal. Therefore, the objective of the current project is to apply the tools of synthetic chemistry to construct new selectors that are capable of recognizing N₂O. 

The increasing concentration of nitrous oxide (N₂O) in the atmosphere is a major, and often understudied, environmental threat. It has ozone-depleting characteristics, a long atmospheric lifetime of 120 years, and global warming potential that is ~270 times that of carbon dioxide (CO₂). Roughly three quarters of all anthropogenic N₂O emissions result from agriculture, in particular nitrogen fertilization of soils – N₂O can moreover act as a marker for nitrogen waste in agriculture. Providing a cost-efficient means to measure local N₂O emissions “on farm” is therefore relevant for the development of next-generation sustainable cropping systems. Within the scope of this project, the researchers aim to develop and test prototype low-power consuming N₂O sensors. These sensors would enable farmers to optimize agricultural yields whilst mitigating environmental influence, reducing over-fertilization, and contributing to achievement of nitrogen reduction pathways.