Sensing environmental contaminants using carbon nanofibers doped tin-oxide composites

Abstract

Enhanced urbanization and industrialization has necessitated use of distributed miniaturized sensors for persistent observation of gases and various other contaminants that may be harmful to our well-being. Several metal oxide viz., SnO₂, ZnO, TiO₂, WO₂, Ga₂O₃, are examined for gas sensing applications for environmental contaminants with applications ranging from monitoring of industrial emission processes to heavily populated urban settings. In the present study, the objective is to investigate bulk sensors via ceramic processing of nanoparticles of several oxides reinforced with carbon nano-fibers (CNFs) and WO₃. The composites are subjected to different pressing pressures and changes in their sensing/detection characteristics is evaluated by their response to different concentrations of ethyl alcohol. It is observed that the sensitivity of SnO₂/CNF sensors for ethyl alcohol increased by almost two fold as compared to that of SnO₂ 8-ton pressed sensor with lower response time.