Fabrication of Pd Doped WO3 Nanofiber as Hydrogen Sensor

Abstract

Pd doped WO 3 fibers were synthesized by electro-spinning. The sol gel method was employed to prepare peroxopolytungstic acid (P-PTA). Palladium chloride and Polyvinyl pyrrolidone (PVP) was dissolved in the sol Pd:WO 3 = 10% molar ratio. The prepared sol was loaded into a syringe connected to a high voltage of 18.3 kV and electrospun fibers were collected on the alumina substrates. Scanning electron microscope (SEM), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques were used to analyze the crystal structure and chemical composition of the fibers after heat treatment at 500 °C. Resistance-sensing measurements exhibited a sensitivity of about 30 at 500 ppm hydrogen in air, and the response and recovery times were about 20 and 30 s, respectively, at 300 °C. Hydrogen gas sensing mechanism of the sensor was also studied.

High Performance Acetylene Sensor with Heterostructure Based on WO3 Nanolamellae/Reduced Graphene Oxide (rGO) Nanosheets Operating at Low Temperature

“…Furthermore, morphological modulation and doping of WO 3 has been utilized to enhance the sensing response. Flower-like WO 3 [ 15 ], Pd-doped WO 3 [ 16 ], and Pt-doped WO 3 [ 17 ] have been reported for WO 3 gas sensing performance promotion. However, drawbacks like high working temperature, poor selectivity still restrain the application of WO 3 gas sensing materials [ 18 ].…”

Metal-seed planting fabrication of W–W18O49 core shell nanoflowers for gas sensors

“…[20][21][22][23] Particularly, the Pt, Pd or their oxide particle-coated WO 3 lms composed of one-dimensional nanostructures (such as nanowires, nanorods, nanoneedles, nanobers and nanotubes) have been proved to have a more outstanding performance in hydrogen detection in previous reports by our group 24,25 and other groups. [26][27][28][29][30][31][32] However, there is a long way to go before this new kind of nanomaterial is used in the actual sensor devices. One of the critical challenges is to controllably synthesize these nanostructures in the pre-designed regions (like the region between two electrodes) in the electronic unit devices, and keep these nanostructures xed and stable on the substrate.…”

Electrospun Polymeric Fibers Coated With Pd As A Sensitive Layer For Hydrogen Detection

“…For environmental monitoring, nowadays exist an increasing interest to detect hydrogen and hydrocarbons that can be found in marine and atmospheric environments, and in the process of oil production. Chemical sensors can be used for gas detection of gas leaks in clean rooms, leak detection in gas compressors, fail monitoring of high-voltage transformers and ripening process of fruits [1][2][3][4][5][6].…”

“…Palladium has been employed as a sensitive layer to detect hydrogen using the change of their conductive properties as a chemioresistor fabricated as thin layers or in the nanofiber matrices [2,5,22]. It has several advantages including a high permeation coefficient [22], ease of adsorption [2,5], workfunction control of the Pd/oxide interface [22], optical and conductive properties changed by the hydrogen content [22].…”