“…(2) for a given analyte, a variety of catalysts can be used to construct the corresponding sensor; and, conversely, the same nanomaterial response to various gas analytes at different catalytic conditions {e.g., nanosized TiO 2 , SrCO 3 , ZrO 2 , Ce 1-x Zr x O 2 , γ-AlOOH, ZnO, YVO 4 :Eu 3+ have all been used as sensing materials for ethanol sensors, and α-Fe 2 O 3 and SnO 2 NTs have both been used in H 2 S sensors [33,40,41,46,47,49,62,78,79]; while nanosized Y 2 O 3 has been used as CTL sensing material in detection of ethyl acetate, benzene, benzaldehyde, trimethylamine and other gases or vapors [50,[56][57][58]68]; and, (3) the range of gas analytes has been broadened to involve, e.g., volatile alcohols, ketones, aldehydes, alkanes, ethers, esters, chloromethanes, and toxic inorganic gases.…”