Tin-Oxide-Nanowire-Based Electronic Nose Using Heterogeneous Catalysis as a Functionalization Strategy

Abstract

An electronic nose (e-nose) strategy is described based on SnO 2 nanowire arrays whose sensing properties are modified by changing their operating temperatures and by decorating some of the nanowires with metallic nanoparticles. Since the catalytic processes occurring on the metal nanoparticles depend on the identity of the metal, decorating the semiconducting nanowires with various metal nanoparticles is akin to functionalizing them with chemically specific moieties. Other than the synthesis of the nanowires, all other steps in the fabrication of the e-nose sensors were carried out using top-down microfabrication processes, paving the way to a useful strategy for making low cost, nanowire-based e-nose chips. The sensors were tested for their ability to distinguish three reducing gases (H 2 , CO, and ethylene), which they were able to do unequivocally when the data was classified using linear discriminant analysis. The discriminating ability of this e-nose design was not impacted by the lengths or diameters of the nanowires used.

Utilization of both-side metal decoration in close-packed SnO2 nanodome arrays for ultrasensitive gas sensing

“…It is apparent that Au decoration enhances gas sensing properties of SnO 2 nanodome arrays owing to two sensitizations such as electronic and chemical sensitizations [26,36,37], which have been already reported in our previous studies [24,25]. The underlying mechanism for the response enhancement by both-side Au decoration is described with schematics in Fig.…”

Unprecedented Insulator-to-Metal Transition Dynamics by Heterogeneous Catalysis in Pd-Sensitized Single Vanadium Oxide Nanowires

“…[38][39][40] To date, many chemical sensors based on novel metal nanoparticles and semiconductor oxides such as tin oxide, tungsten oxide, titanium dioxide, etc., have been reported. [41][42][43][44] However, a major disadvantage is that these sensors operate only at temperatures greater than 100°C (may show low sensitivity at lower temperatures), thus resulting in higher power consumption and a reduction in their stability. On the contrary, a VO 2 based MIT sensor is able to operate at temperatures lower than the MIT temperature of (~ 68 °C) and can show ultra-high sensitivity of ~ 1000 fold enhancement.…”

Polarity Index Dependence of M13 Bacteriophage-based Nanostructure for Structural Color-based Sensing

“…Innovative structures fabricated using M13 bacteriophage have been used to produce piezoelectric nanostructures, virusbased full-color pixels, and highly effective surface plasmon resonance (SPR) sensors [1][2][3][4][5][6][7][8][9][10]. Furthermore, in less than a decade, M13 bacteriophage-based color sensor systems have shown great potential for the detection of cancer cells and various target chemicals, such as TNT, antibiotics, and endocrine-disrupting chemicals (EDCs) [11][12][13][14][15][16][17][18][19].…”