Electrospun one-dimensional nanostructures: a new horizon for gas sensing materials

Abstract

Electrospun one-dimensional (1D) nanostructures are rapidly emerging as key enabling components in gas sensing due to their unique electrical, optical, magnetic, thermal, mechanical and chemical properties. 1D nanostructures have found applications in numerous areas, including healthcare, energy storage, biotechnology, environmental monitoring, and defence/security. Their enhanced specific surface area, superior mechanical properties, nanoporosity and improved surface characteristics (in particular, uniformity and stability) have made them important active materials for gas sensing applications. Such highly sensitive and selective elements can be embedded in sensor nodes for internet-of-things applications or in mobile systems for continuous monitoring of air pollutants and greenhouse gases as well as for monitoring the well-being and health in everyday life. Herein, we review recent developments of gas sensors based on electrospun 1D nanostructures in different sensing platforms, including optical, conductometric and acoustic resonators. After explaining the principle of electrospinning, we classify sensors based on the type of materials used as an active sensing layer, including polymers, metal oxide semiconductors, graphene, and their composites or their functionalized forms. The material properties of these electrospun fibers and their sensing performance toward different analytes are explained in detail and correlated to the benefits and limitations for every approach.

Review of advanced sensor devices employing nanoarchitectonics concepts

“…Detection systems for various chemical, physical, environmental, and biological targets, so-called sensors, have been continuously explored [1–4]. Although their usefulness was recognized even in the early stages of modern science and technology, the importance of sensors has been recently re-evaluated in the context of current research developments.…”

Electrospun Metal Oxide Nanofibers and Their Conductometric Gas Sensor Application. Part 2: Gas Sensors and Their Advantages and Limitations

“…Earlier in [15][16][17][18][19][20][21][22][23], it was shown that one of the most promising fields of application of metal oxide 1D nanomaterials is the development of conductometric gas sensors based on them. As it is followed from discussions presented in Part 1 of our article [24], metal oxide nanofibers are also a promising material for these applications, since a nanofiber mat, forming a gas-sensitive layer, is characterized by high porosity and a large surfaceto-volume ratio [12,25,26]. In addition, the metal oxide crystallites in nanofibers can have an extremely small size [27].…”

“…As it was indicated before, nanofibers are not 1D structures, in the classical understanding, as metal oxide nanowires or nanobelts and nanotubes. However, research has shown that the features of the nanofiber configuration and the size factor play a positive role in the development of gas sensors based on nanofibers [12,26,[65][66][67][68][69][70][71]. As mentioned above, metal oxide nanofibers, which usually have a diameter in the range of 50-1000 nm and a length from several micrometers to centimeters and meters, have many unique properties of gas-sensitive materials, such as a very large surface area per unit mass, high porosity and a small size of crystallites that form nanofibers.…”

“…In recent years, noticeable interest has been shown in one-dimensional (1D) metal oxide nanomaterials [1][2][3][4][5][6][7][8][9][10] such as nanowires, nanobelts and nanotubes. Many authors also include metal oxide nanofibers (NFs) in this group of nanomaterials [11][12][13][14], although in nature, they differ from classical 1D nanomaterials. Unlike classical 1D nanomaterials, which are monocrystalline in nature, metal oxide nanofibers are amorphous or polycrystalline.…”

Phenyliminophenothiazine based self-organization of polyaniline nanowires and application as redox probe in electrochemical sensors

“…They are also applicable as nanosized analogs of metallic conductors of macroscopic instruments. Large surface area maintains an interest in such materials in gas sensing 3 and liquids analysis 4 . Among variety of such materials, emeraldine, a semi-oxidized form of polyaniline, is most attractive due to easy preparation, low toxicity and low electric resistance 5 .…”