Pulsed current-voltage electrodeposition of stoichiometric Bi₂Te₃ nanowires and their crystallographic characterization by transmission electron backscatter diffraction

Abstract

Bi2Te3 nanowires with diameters ranging from 25 to 270 nm, ultra-high aspect ratio, and uniform growth front were fabricated by electrodeposition, pulsing between zero current density during the off time and constant potential during the on time (pulsed-current-voltage method, p-IV). The use of zero current density during the off time is to ensure no electrodeposition is carried out and the system is totally relaxed. By this procedure, stoichiometric nanowires oriented perpendicular to the c-axis is obtained for the different diameters of porous alumina templates. In addition, the samples show a uniform growth front with ultra-high aspect ratio single crystal nanowires. The high degree of crystallinity was verified by transmission electron backscatter diffraction. This characterization revealed that the nanowires present both large single crystalline areas and areas with alternating twin configurations.

3D Bi2Te3 Interconnected Nanowire Networks to Increase Thermoelectric Efficiency

“…By analogy to classical fluid mechanics, this term can be interpreted as a heat viscosity effect. Accordingly, the effective thermal conductivity of electrodeposited 1D nanowires is reduced in comparison to electrodeposited thin films 10 because collisions reduce the heat flux in a region near the wire boundary (see Figure 2 c, inset 1, and Supporting Information Figure S5 , where the predicted and measured lattice conductivities are displayed for different 1D nanowire diameters). Alternatively, according to a kinetic interpretation, the reduction of the effective thermal conductivity in the wire can be attributed to a suppression of phonons with a mean free path larger than the diameter of the wire.…”

“…They were then sonicated to obtain arrays of tens of nanowires connected with the transversal nanocanals. The resulting 3D Bi 2 Te 3 nanowire networks were carefully dispersed on carbon grids avoiding structural bending or twisting (see Figure c), for electron tomography measurements and transmission electron backscatter diffraction (t-EBSD) . The transmission Kikuchi diffraction (TKD) analysis along the 3D nanostructure was performed using a Tescan MIRA SEM instrument (TESCAN, Czech Republic), with beam conditions of 30 kV and 5 nA, using a tilt of 20° and 3 mm of working distance.…”

Localization and Directionality of Surface Transport in Bi2Te3 Ordered 3D Nanonetworks

“…Bi 2 Te 3 was grown by pulsed electrodeposition inside the 3D-AAO structure in a three-electrode cell configuration as reported in refs and . The deposition process was controlled with a potentiostat (Autolab PGSTAT 302N) with Nova 2.0 software.…”

Recent progress in the electrochemical deposition of ZnO nanowires: synthesis approaches and applications

“…Due to its simplicity and robustness, hard-template electrodeposition is the most widely applied strategy for electrosynthesizing polymeric, metallic, alloyed, or semiconducting nanowires or nanorods, one that offers controlled properties and the controlled definition of shape 29,[98][99][100][101][102][103][104][105] .…”