Carbon‐Nanotube‐Templated, Sputter‐Deposited, Flexible Superconducting NbN Nanowire Yarns

Abstract

Flexible superconducting yarns consisting of sputter‐deposited NbN nanowires on highly aligned carbon nanotube (CNT) array sheets are reported. In the microscopic view, the NbN nanowires are formed on top of individual CNT fibrils, and the superconductivity property of the twist‐spun NbN–CNT yarn system is comparable to that of a typical NbN thin film on a normal solid substrate. Because of its intrinsic porosity, the system exhibits superior mechanical flexibility with a small bending radius. It also remains a superconducting state even when subjected to severe mechanical deformations, primarily due to the proximity superconductivity through carbon nanotube bundles. The results demonstrate the possibility of fabricating flexible superconducting yarns in a conventional thin‐film deposition process, using ultraflexible free‐standing CNT sheets as a template. In addition, preliminary tests on reducing the normal‐state resistance toward superconducting cable applications are presented.

High-performance solid-state Zn batteries based on a free-standing organic cathode and metal Zn anode with an ordered nano-architecture

“…1f show the D-band, G-band and 2Dband peaks at 1350, 1580 and 2691 cm À1 of the CNT lm, representing the disordered features of sp 2 domains, the rst-order scattering of the E 2g mode, and the resonance of two phonons, respectively. 30,31 Aer deposition of PANI nanowires on the CNT lm, a series of characteristic peaks of PANI appeared overlapping with the D and G-band peaks of the CNT lm at 1169, 1222, 1343, 1496, 1588 and 1620 cm À1 , which are assigned to the C-H in-plane bending of the quinoid ring, C-C ring deformation of the quinoid ring, C]N stretching of the quinoid ring, C]C stretching vibration of the quinoid ring, C-H bending of the benzenoid ring, and C-C stretching of the benzenoid ring, representing the deposition of PANI nanowires. 32,33 The exible Zn@CC anode was fabricated by a facile electrodeposition method.…”

Anomalous Negative Resistance Phenomena in Twisted Superconducting Nanowire Yarns

“…More details regarding the sample fabrication were reported in a previous work. 24 Notably in Figure 1e, the relative contrast in the SEM image of the yarn resulted from the alternation of the NbN-coated part in Figure 1d (which came from the top side of the CNTsheet substrate facing the NbN target during the sputtering process) and the bare CNT-sheet part (which mostly came from the bottom side of the substrate opposite the NbN target direction and has a morphology similar to that in Figure 1c). They are depicted as yellow and black strips, respectively, in the schematic, and the conventional four-probe contacts were applied to the NbN-CNT yarn for the electrical resistance measurement as in the photograph.…”

“…The detailed interface morphology between NbN and CNT can have various forms inside the twist-spun dual Archimedean scroll yarns for the real NbN−CNT yarn sample. 24 To check the reliability of the model described in the foregoing paragraph, we examined all possible four-probe resistance measurement configurations with the equivalent circuit model in Figure 4c. As summarized in Table 1, both ends of the sample are assigned to an input (i.e., I + for A 1 or A 2 in Figure 4c) and an output (i.e., I − for D 1 or D 2 ) of the current, and the two voltage probes are connected to four possible locations (i.e., V + and V − for two of B 1 , B 2 , C 1 , and C 2 ) in the intermediate region.…”

Fabrication of High Specific Electrical Conductivity and High Ampacity Carbon Nanotube/Copper Composite Wires

“…[ 8 ] However, when CNTs are combined to form a useable wire, these properties drop many order of magnitude. [ 9 ] Over the last decade there has been a great progress in creating CNTs wires using wet spinning (spinning using super‐acids [ 10–13 ] and surfactant‐based coagulation spinning [ 14–31 ] ) and dry spinning (aligned forest‐array spinning [ 32–54 ] and direct spinning of CNTs aerogel [ 40,55–87 ] ). Good quality CNTs wires are now commercially available.…”