Mo₆S₃I₆ Nanowire Network Vapor Pressure Chemisensors

Abstract

Mo6S3I6 nanowire networks of interest are found to change their resistance in response to the presence of analyte vapors. The vapor sensing behavior is quantitatively described very well phenomenologically in terms of the concentration of adsorbed analyte molecules in the contact tunneling junctions, and an expression is derived for the dynamics and sensor resistance in terms of analyte vapor pressure. The time response of the sensor is observed to follow simple adsorption–desorption kinetics. The network sensor shows very clear selectivity, whereby the response is related to the dipole moment of the analyte. The response function favors rapid detection of small analyte concentrations.

Gas Sensing Properties of NiSb2O6 Micro- and Nanoparticles in Propane and Carbon Monoxide Atmospheres

“…Among the gases of which there is a broad interest for being monitored are oxygen (O 2 ), carbon monoxide (CO), carbon dioxide (CO 2 ), sulfur dioxide (SO 2 ), nitrogen oxides (NO and NO 2 ), hydrogen sulfide (H 2 S), methane (CH 4 ), ethanol (C 2 H 5 OH), and propane (C 3 H 8 ) [ [6,7], as well as the compounds LaFeO 3 , Mo 6 S 3 I 6 , and CuCrO 2 [8][9][10]. These materials are nowadays considered as extraordinary gas detectors because they possess good physical and chemical stability in different atmospheres.…”

Inorganic molecular wires: Physical and functional properties of transition metal chalco-halide polymers

“…33, are found to change their resistance in response to the presence of analyte vapors [66,67]. The response was found to be arising from the contacts between bundles, and not due to a change of resistance of the nanowires.…”

“…Remarkably, recent experiments with reduced circuit size were found to significantly reduce the noise, effectively reducing the detection limit, which increases their potential for application [67]. Presently multi-element chemiresistive MoSI sensors using chemically different contact elements are being tested for discriminatory detection of gases and vapors.…”

“…This type of array sensor has numerous advantages over existing percolative graphite-polymer chemisensors. Particularly because it does not rely on a percolation threshold for operation, is has greater operating range and better chemical inertness [67].…”

“…The response function can be modeled in terms of chemisorptions' kinetics of the analyte under equilibrium conditions equilibrium in the contact region[67]. The shown data are for a number of common analytes.…”