Application of membranes and filtering films for gas sensors improvements

Thin film SnO2-based gas sensors: Film thickness influence

“…As we indicated earlier, films with such a thickness have very low sensitivity to ozone [53]. Due to the high activity of ozone, the top layers of the SnO 2 film could act as a filter [54], which at a sufficient film thickness would prevent a deep penetration of ozone into the gas sensing material. The obtained results also cannot be applied to the SnO 2 films deposited at temperatures higher than 500 • C. As has already been established [13], the decrease in sensor response for these films already takes place at d > 100 nm.…”

Ambient temperature selective ammonia gas sensor based on SnO2-APTES modifications

“…Human breath contains a wide variety of volatile organic compounds which are polar or nonpolar, oxidant or reductant. It's well known that SnO2 sensor which usually operates at temperature between 350-500 °C can give a response to most of these types of gases, unfortunately without distinction (selectivity) or even with compensating effect for oxidant/reducing gases [47]. Field effect transistors functionalized with ester end group have shown responses to a wide variety of volatile organic compounds like alcohols and alkanes [39].…”

Successive ionic layer deposition (SILD) as a new sensor technology: synthesis and modification of metal oxides

“…Oxides formed by the SILD method could possibly be used as precoats in catalytically active filters, by separating the noble metals from the gas sensing metal oxides. The effectiveness of such a possibility has been discussed in [29].…”