TiO2 nanofibers decorated with monodispersed WO3 heterostruture sensors for high gas sensing performance towards H2 gas

Abstract

A simple spin coating method was used to prepare the WO 3 -TiO 2 heterostructural nano bers (HNFs).Various kinds of techniques, including XRD, SEM, TEM, EDS and XPS, have described the structures, chemical constitutions and morphologies of the samples. Following the decoration of the WO 3 nanocubes on the surface of TiO 2 nano bers, XPS ndings con rmed the presence of W 5+ and the excess proportion of both chemisorbed reactive oxygen and oxygen vacancies. WO 3 incorporated TiO 2 thin lm sensor showed high sensing response (78%), rapid response (20 s) and recovery time (23 s) with respect to other gas molecules (NH 3 , NO 2 , LPG and SO 2 ). The nding demonstrates that the WO 3 -TiO 2 sensor showed good selective response towards H 2 gas. A unique path was created by this work to build hetero-highly ordered mesoporous metal oxides junctions for applications in H 2 gas sensor based devices.

Gas Sensing Technology for the Detection and Early Warning of Battery Thermal Runaway: A Review

“…Combining different MOSs (two or more) to construct heterostructures (p–n junction, p–p junction, and n–n junction) can effectively improve gas sensitivity, which may benefit from the introduction of more electron depletion layers, the change of energy band structure, the increase of adsorption sites, or the improvement of the catalytic activity of materials. − However, the construction of heterostructures will also lead to an increase in operating temperature in some cases due to a higher activation barrier at the material interfaces. , This feature is conducive to the gas sensors being applied in some high-temperature conditions but will inevitably increase the power consumption. Kumaresan et al synthesized nanofibers with n-WO 3 /n-TiO 2 heterostructure by simple spin-coating method, in which WO 3 nanoparticles were uniformly loaded on the surface of TiO 2 NFs. Compared with single MOS, n-WO 3 /n-TiO 2 exhibited a more excellent H 2 -sensing performance.…”

“…85,86 This feature is conducive to the gas sensors being applied in some high-temperature conditions but will inevitably increase the power consumption. Kumaresan et al 87 synthesized nanofibers with n-WO 3 /n-TiO 2 heterostructure by simple spin-coating method, in which WO 3 nanoparticles were uniformly loaded on the surface of TiO 2 NFs. Compared with single MOS, n-WO 3 /n-TiO 2 exhibited a more excellent H 2sensing performance.…”

Advances in functional guest materials for resistive gas sensors

“…Kumaresan et al 108 synthesized nanofibers with the n-WO 3 /n-TiO 2 heterostructure by uniformly loading WO 3 nanoparticles (guest) on the TiO 2 nanofiber (host) surface through a simple spin coating method. Compared to the original TiO 2 , n-WO 3 /n-TiO 2 exhibited a more excellent H 2 sensing performance.…”

Nanoporous WO3 Gasochromic Films for Gas Sensing

“…In recent decades, due to its high hydrogen diffusion ability nanoporous tungsten oxide (WO 3 ) has been widely applied in smart color-switchable films, 1 photocatalysts, 2 solar cells, 3 humidity sensors, 4 and gas sensors. 5 In contrast to other colorswitchable films, 6,7 gasochromic films, which appear blue when exposed to hydrogen and transparent when exposed to oxygen, have received considerable attention. 8 Gasochromic films only require a nanoporous layer (WO 3 ) and a catalyst layer (Pd), 9 which can lower the manufacturing cost and better facilitate the promotion and production of optical gas sensing and energy-saving applications.…”

“…In recent decades, due to its high hydrogen diffusion ability nanoporous tungsten oxide (WO 3 ) has been widely applied in smart color-switchable films, photocatalysts, solar cells, humidity sensors, and gas sensors . In contrast to other color-switchable films, , gasochromic films, which appear blue when exposed to hydrogen and transparent when exposed to oxygen, have received considerable attention .…”