Metal Oxide Nanoarrays for Chemical Sensing: A Review of Fabrication Methods, Sensing Modes, and Their Inter-correlations

Abstract

In recent years, engineered nanostructure assemblies such as nanowire arrays have attracted much research attention due to their unique chemical and functional characteristics collectively. The engineered nano-assemblies usually carry the characteristics distinct from bulk as a result of a size effect in their comprised elemental building blocks. The nanoscale size induced high surface-to-volume ratio is a fundamental attribute responsible for various chemical and physical properties required in various technologically important applications such as catalysts and sensors. This review article surveys the latest progress in engineered metal oxide nanostructure arrays, i.e., nanoarrays, for advanced chemical sensors' design and application. It starts with an overview of gaseous chemical sensors followed by surveys of various fabrication methods and routes for metal oxide nanoarrays. Different sensing modes and corresponding applications have been highlighted in the mixed gaseous chemical sensing, which provides new approaches and perspectives to meet the challenges of selective gas sensing, such as the cross-sensitivity and inter-correlation of multiple sensing signals.

Current Trends in Nanomaterials for Metal Oxide-Based Conductometric Gas Sensors: Advantages and Limitations. Part 1: 1D and 2D Nanostructures

“…That is why since 2000, the development of gas sensors based on 1D structures has become one of the most popular areas of research in the field of gas sensors [ 5 , 86 , 106 , 144 , 145 , 149 , 214 , 215 , 216 ]. If there is an interest only in the performances of 1D-based gas sensors, then I recommend referring to the reviews [ 144 , 204 , 217 , 218 , 219 , 220 , 221 , 222 , 223 , 224 , 225 ], where such information is presented. As with conventional gas sensors, based on nanostructured crystallites, the sensing properties of individual NWs are affected by the NW diameter, the NW synthesis procedure, the feature of surface functionalization, and the reactions that occur on the NW surfaces.…”

A Short Review on Various Engineering Applications of Electrospun One-Dimensional Metal Oxides

“…Gas sensors based on semiconductor metal oxides are widely used in many areas, including chemical pollution control in air and rooms, alarms to detect the threat of poisonous substances and even medical diagnostics performed on the basis of a patient’s breath. The popularity of these types of sensors is due to their high sensitivity, low cost and ease of manufacture, as well as their compatibility with modern electronic devices [ 129 , 130 , 131 , 132 , 133 , 134 ].…”

Fabrication and Application of TiO2 Based Thin Film Capacitive Biosensor towards Fruit Freshness Detection on Silicon Substrate

“…Titanium dioxide is an n-type wide band gap semiconductor that is chemically stable, inexpensive and environment-friendly [18]. Different metal oxide based thin film sensors have been fabricated for different sensing applications [19,20]. WO 3 and TiO 2 are widely used in sensing applications owing to high stability, high sensitivity and nontoxicity.…”