Detecting CO2 Using Nanowire Chemiresistive Sensor for Monitoring Air Quality in Enclosed Space Habitat
Year: 2014
Type: article
Abstract: Monitoring carbon dioxide (CO 2 ) concentration within an enclosed space habitat is critical to ensuring the safety of astronauts and their overall well-being in space because CO 2 produced through respiration can accumulate rapidly within closed spaces.If not properly managed, the space crew could experience increased respiratory rate, headaches and hyperventilation, impaired vision and hearing, and decreased cognitive abilities.Currently, non-dispersive infrared (NDIR) spectroscopy is considered the most sensitive system (for a calibrated condition of 21.1 °C and 1 atmosphere) for detecting CO 2 during manned space flight.However, measurements are not reliable and error rate increases with variation of temperature, pressure and composition of gas.A more robust and accurate sensor system is required for reliable measurement and monitoring of CO 2 under temperature/pressure variations.InnoSense LLC (ISL) explores the development of a polymer nanowire sensor as a potential robust and real-time air-quality monitoring system for accurate, reliable and sensitive detection of CO 2 in enclosed spaces.The nanowire sensor is a chemiresistive junction composed of two solid state electrodes bridged by conducting polymer materials in the form of ~70-150 nm diameter wires.The electron transport properties of the sensor change upon exposure to CO 2 .The nanowire sensors can detect CO 2 in the 0-10,000 ppm range with high sensitivity (~50 ppm) and selectivity in the presence of 0-80% relative humidity and temperatures from 0-60 °C.The sensor response time to CO 2 , across all measured concentration ranges, was 2 minutes.The sensors are capable of detecting CO 2 reversibly and self-regenerate to baseline signal within 30 minutes upon CO 2 removal.
Institutions: Los Alamos National Laboratory, InnoSense (United States)
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2276626917