Synthesis and properties of NiCo crossed nanotube networks

This paper reports on the synthesis and the characterization of magnetic and magneto-transport properties of electrically interconnected Ni 1 − x Co x alloy crossed nanotube networks. The alloy nanotube networks have been fabricated by an adapted electrochemical technique based on a dealloying method previously used for the fabrication of pure Ni nanotubes. Here, we demonstrate that this synthesis approach can be adapted to fabricate NiCo alloy nanotubes with Co contents ( x ) up to 27%. Increasing the Co content within this range has revealed an increase in the nanotube walls that is accompanied by an increase in the effective magnetic anisotropy, which is attributed to a reinforcement of the magnetostatic field along the nanotube axis. Magneto-transport measurements are consistent with the typical behavior observed previously in magnetic nanotubes, where the dominant magnetization reversal process involves the propagation of vortex-like domain walls. Furthermore, the field position of the drop in resistance close to zero field is consistent with the coercive field, which depends on the nanotube material and wall thickness. The possibility of synthesizing complex electrically interconnected nanoarchitectures, such as crossed nanotube networks made of various ferromagnetic materials, using electrochemical deposition techniques is of particular interest for the development of potential applications in magnetic sensing devices, neuromorphic computing, and spintronics. • It has been demonstrated that NiCo alloy crossed nanotube networks can be fabricated using an adapted electrochemical dealloying technique. • The alloy composition can be precisely adjusted with a Co content below approximately 30%. • Both magnetic anisotropy and nanotube wall thickness increase as the Co content increases. • The magneto-transport behavior depends on the Co content and is dominated by magnetization reversal processes involving the propagation of vortex-like domain walls.