An enrichment method to detect low concentration formaldehyde

作者:Wang Jing*; Liu Li; Cong Song Ying; Qi Jin Qing; Xu Bao Kun
来源:Sensors and Actuators B: Chemical , 2008, 134(2): 1010-1015.
DOI:10.1016/j.snb.2008.07.010

摘要

A semiconductor gas sensor of tin oxide doped with hydroxyl (OH) functionalized multi-wall carbon nanotubes (MWCNTs) was fabricated for detecting indoor formaldehyde concentration. The response of the MWCNTs-doped SnO2 sensor was much higher than that of an undoped SnO2 sensor. In order to detect low concentration formaldehyde, a novel enrichment method utilizing active carbon was applied. The response of the sensor was obviously increased by the application of the enrichment method. The lowest concentration of formaldehyde gas detected by a 5 wt% MWCNTs-doped SnO2 sensor was 0.03 ppm.