Morphologies, Young’s Modulus and Resistivity of High Aspect Ratio Tungsten Nanowires

Abstract

High aspect ratio tungsten nanowires have been prepared by selective dissolution of Nickel-aluminum-tungsten (NiAl−W) alloys which were directionally solidified at growth rates varying from 2 to 25 μm/s with a temperature gradient of 300 K·cm−1. Young’s modulus and electrical resistivity of tungsten nanowires were measured by metallic mask template method. The results show that the tungsten nanowires with uniform diameter and high aspect ratio are well aligned. The length of tungsten nanowires increases with prolongation of etching time, and their length reaches 300 μm at 14 h. Young’s modulus of tungsten nanowires is estimated by Hertz and Sneddon models. The Sneddon model is proper for estimating the Young’s modulus, and the value of calculating Young’s modulus are 260–460 GPa which approach the value of bulk tungsten. The resistivity of tungsten nanowires is measured and fitted with Fuchs−Sondheimer (FS) + Mayadas−Shatzkes (MS) model. The fitting results show that the specific resistivity of W nanowires is a litter bigger than the bulk W, and its value decreases with decreasing diameter.

Preparation of polycrystalline tungsten nanofibers by needleless electrospinning

“…Tungsten nanowires are another type of morphology. They are produced by a range of methods, including the hard templating by mesoporous silica SBA-15 [36] or mesoporous carbon [37], the chemical vapor transport process from W filament [38], Ni-catalyzed vapor-phase decomposition of WO 2 (OH) 2 [39,40], decomposition of W(CO) 6 or WF 6 by a focused ion beam [41,42], electric field [43,44], and an electron beam [45][46][47], carbothermal reduction of WO 3 /CTAB lamellar composites [48], and especially by directional solidification and selective electrochemical dissolution of NiAl-W eutectic alloys [49,50] resulting in single-crystalline nanowires with extraordinary lengths and diameters around 200 nm.…”

Ga‐Based Liquid Metals: Versatile and Biocompatible Solutions for Next‐Generation Bioelectronics

“…[87,88] Compared to the conventional rigid electrodes, the elastic modulus of Ga-based LM electrodes is relatively close to the soft neural tissue. [89] Guo et al developed an implantable neural microelectrode array, comprising In-Ga alloy electrodes and 500 μm polydimethylsiloxane (PDMS) encapsulation. [90] The authors demonstrated that the LM electrodes with PDMS exhibit elastic modulus similar to that of the dura mater and skin by analyzing the stress-strain curve.…”

“…[ 87,88 ] Compared to the conventional rigid electrodes, the elastic modulus of Ga‐based LM electrodes is relatively close to the soft neural tissue. [ 89 ] Guo et al. developed an implantable neural microelectrode array, comprising In‐Ga alloy electrodes and 500 µm polydimethylsiloxane (PDMS) encapsulation.…”