“…For a brief overview of the current research status of isoprene sensing SMOs, Table 1 summarises the materials studied and their sensing performances published during recent years (2020-2023). [13][14][15][16][17][18][19][20][21][22][23][24][25] The most investigated SMOs for VOC sensing were transition-metal oxides, including In 2 O 3 , SnO 2 , WO 3 , MoO 3 , TiO 2 , ZnO, and Co 3 O 4 , 26 which were usually doped with a small amount of another element (or elements) for higher sensitivity to a particular gas (i.e., the selectivity for this gas). Several of the above SMOs, i.e., In 2 O 3 , 20 ZnO, 17 WO 3 , 21 and Co 3 O 4 , 25 have been studied for isoprene sensing and a number of elements, including Au, 17,21 Pt, 16 Pd, 20 Ti, 27 and Si, 12 have been tried as dopants.…”