Growth and characterization of tungsten carbide nanowires by thermal annealing of sputter-deposited WCx films

Abstract

In this letter, the growth of dense W2C nanowires by a simple thermal annealing of sputter-deposited WCx films in nitrogen ambient is reported. Straight nanowires with a density of 250–260μm−2 and length∕diameter in the range of 0.2–0.3μm∕13–15nm were obtained from the 700°C-annealed samples, which exhibit good electron field emission characteristics with a typical turn-on field of about 1.7V∕μm. The self-catalytic growth of W2C nanowires is attributed to the formation of α-W2C phase caused by carbon depletion in the WCx films during thermal annealing.

Development of Gas Sensors Based on Tungsten Oxide Nanowires in Metal/SiO2/Metal Structure and Their Sensing Responses to NO2

“…The present results are different from those of our previous work. 16,17) in annealing temperature. It is suspected that, because the present sample was subjected to PECVD and BOE, it might contain extra oxygen-related particles inside the device structure.…”

“…In contrast, nanosized materials such as carbon nanotubes (CNTs), 12) SnO 2 nanoribbons, 13) SnO 2 nanowires, 14) In 2 O 3 nanowires, 15) and tungsten-based nanowires, [16][17][18][19][20][21] have attracted much attention in the fabrication of SS sensors because they have very high SVRs and good response for chemical sensing. In recent years, nanosensors with superior characteristics, such as high sensitivity, high response speed, and applicability to room-temperature operation, have been demonstrated.…”

“…[16][17][18][19][20][21] TONWs with typical diameters of 17 -23 nm, typical lengths of 0.2 -0.3 mm, and typical densities of 150 -720 mm À2 have been successfully grown. Essentially, the use of TONWs as gas sensing materials is very attractive because they exhibit physical and chemical properties that are very different from those of their bulk or film counterparts.…”

On-Chip Tungsten Oxide Nanowires Based Electrodes for Charge Injection

“…between nanowires and tungsten thin film was analyzed by SAD and it was found out that interfacial phase has d-spacings 2.36 Å and 1.36 Å corresponds to the phases -W 2 C(002) and -W 2 C(103), respectively (Wang et al, 2004). Chemical bonding states on the surface of the tungsten thin film and the nanowires were investigated by XPS (not shown).…”

Estudo da atividade e da estabilidade de eletrocatalisadores de Pt suportados em carbono, monocarbeto e dióxido de tungstênio frente a reação de redução de oxigênio

“…Efeitos sinérgicos são evidenciados pela adição de carbeto de tungstênio em metais como a Pt, que podem favorecer a redução do uso deste metal nobre [52]- [55]. Alguns autores acreditam que a dimensão e a dispersão das partículas de Pt podem ser melhoradas significativamente se a Pt for reduzida diretamente na superfície de WC/C, havendo consequentemente um aumento de atividade catalítica para a RRO [56].…”