Solid state carbon dioxide sensor

Abstract

A solid state, carbon dioxide (CO) sensor configured for sensitive detection of COin both dry and moist conditions. The COsensor utilizes a composite sensing material that detects COin the range of 100 ppm to 10,000 ppm. The sensing material is composed of O-MWCNTs and a metal oxide functionalizing agent, such as iron oxide (FeO) nanoparticles. The material has an inherent resistance and conductivity that is chemically modulated as the level of COincreases. The COgas molecules that are absorbed into the carbon nanotube composites cause charge-transfer and changes in the conductive pathway causes changes in conductivity of the composite sensing material. This change in conductivity provides a specificity and sensitivity for COdetection. The COsensor can be easily integrated into existing electronic circuitry and hardware configurations, including the hardware of a mobile computing device, such as a smart phone or tablet device.