Multiplexed Carbon Nanotube Sensing film for Smart Soil Application

Abstract

For smart management of soil, continuous monitoring of nitrogen (N) is essential. Current monitoring systems are either expensive or insensitive to nitrogen. The objective of this thesis is to develop an array of single walled carbon nanotube (SWCNT) sensors in order to monitor ammonia and NOx diffused from the soil in a crop field. The array includes a pure SWCNT sensor, a nafion-coated SWCNT sensor and a polyethylenimine-coated SWCNT sensor. Using ammonia gas, the sensitivity and specificity of a SWCNT sensors are characterized. The calibrated sensors are tested for sand mixed with fertilizer in order to measure the concentration of ammonia and NOx. The detection limit is evaluated in terms of the weight ratio of sand to fertilizer. The developed sensor with light weight and a small form factor can be embedded in an unmanned vehicle for smart management of soil and other environment.