Toward new gas-analytical multisensor chips based on titanium oxide nanotube array

Abstract

Reliable environmental monitoring requires cost effective but highly sensitive and selective gas sensors. While the sensitivity of the sensors is improved by reducing the characteristic dimensions of the gas-sensing material, the selectivity is often approached by combining the sensors into multisensor arrays. The development of scalable methods to manufacture such arrays based on low-dimensional structures offers new perspectives for gas sensing applications. Here we examine an approach to produce multisensor array chips based on the TiOx nanotube layers segmented by multiple Pt strip electrodes. We study the sensitivity and selectivity of the developed chip at operating temperatures up to 400 °C towards organic vapors in the ppm range. The results indicate that the titania nanotubes are a promising material platform for novel cost-effective and powerful gas-analytical multisensor units.

Light-Tuned DC Conductance of Anatase TiO2 Nanotubular Arrays: Features of Long-Range Charge Transport

“…The aTNTA layer has been fabricated by electrochemical anodization of the titanium foil 0.127 mm thick (99.7%, Sigma-Aldrich, St. Louis, MO, USA), according to the earlier reported protocols [ 27 ]. In brief, the process has been carried out at constant electrical bias of 30 V for approx.…”

“…However, a bigger part of the surface contains partially ordered tightly-packed nanotubes with double-sided shells having irregular circle shapes ( Figure 1 c). Some brighter areas observed in Figure 1 b relate to spatial distortions of the aTNTA [ 27 ]. The appeared nanotubes stand perpendicular to the substrate.…”

ZnO Nanowire Application in Chemoresistive Sensing: A Review

“…While, in biosensors, different analytes can be targeted with a special biomolecule, it is an especially difficult task to differentiate among the same type of gases (oxidizing or reducing), since depletion layer width change and consequently response will be in the same direction. Selective recognition of the gases can be addressed by variations in chemical adsorption and dissociation of the target gases at the NW surface; therefore, NW sensor selectivity can be approached by several methods: NW geometry control [ 36 , 37 ], NW functionalization [ 38 , 39 ], selective contact formation [ 40 ], heterojunction [ 41 ], operating temperature modulation [ 42 ], and sensor array formation [ 43 ].…”

Исследование Формирования Слоев Станната Цинка Методом Рентгеновской Фотоэлектронной Спектроскопии

“…При этом активно анализируются возможности замены нагревателей источниками оптического излучения [6]. Другим направлением является повышение селективности путем создания мультисенсорных систем [7]. Также для увеличения селективности газовых сенсоров используется создание перколяционных кластеров, возникающих на границах зерен оксидов металлов при изменении состава поверхностных фаз [8,9].…”