2026-04-18T07:41:51Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1273272025-12-04T21:30:38Zcom_2072_1057col_2072_478812col_2072_478917

00925njm 22002777a 4500 dc Müller, Gerhard author Prades García, Juan Daniel author Hackner, Angelika author Ponzoni, Andrea author Comini, Elisabetta author Sberveglieri, Giorgio author 2019-01-16T11:19:03Z 2019-01-16T11:19:03Z 2018-12-06 2019-01-16T11:19:03Z Surface ionization (SI) provides a simple, sensitive, and selective method for the detection of high-proton affinity substances, such as organic decay products, medical and illicit drugs as well as a range of other hazardous materials. Tests on different kinds of SI sensors showed that the sensitivity and selectivity of such devices is not only dependent on the stoichiometry and nanomorphology of the emitter materials, but also on the shape of the electrode configurations that are used to read out the SI signals. Whereas, in parallel-plate capacitor devices, different kinds of emitter materials exhibit a high level of amine-selectivity, MEMS (micro-electro-mechanical-systems) and NEMS (nanowire) versions of SI sensors employing the same kinds of emitter materials provide significantly higher sensitivity, however, at the expense of a reduced chemical selectivity. In this paper, it is argued that such sensitivity-selectivity trade-offs arise from unselective physical ionization phenomena that occur in the high-field regions immediately adjacent to the surfaces of sharply curved MEMS (NEMS) emitter and collector electrodes. Detectors de gasos Ionització de gasos Gas detectors Ionization of gases Sensitivity-selectivity trade-offs in surface ionization gas detection