Ni-P nanoglass prepared by multi-phase pulsed electrodeposition

Abstract

NiP nanoglass consisting of nanometer-sized amorphous grains separated by amorphous interfaces was prepared by a specially designed multi-phase pulsed electrodeposition technique. The microstructure of the deposited NiP nanoglass was confirmed by X-ray diffraction, high-resolution transmission electron microscopy, small-angle X-ray scattering, and X-ray photoelectron spectroscopy. The formation of the NiP nanoglass, which is characterized by inhomogeneities on the nanometer length scale, is achieved via proper control of the rate of cluster formation and cluster growth by a multi-phase pulsed electrodeposition process.

Engineering medium-range order and polyamorphism in a nanostructured amorphous alloy

“…Figure 3b illustrates the differential reduced PDF pattern, G(r), obtained by a fast Fourier transform (FFT) of the difference S(Q), which was obtained from ED Ni 82 P 18 alloy pattern after subtracting 50% of the MG Ni 82 P 18 ribbon pattern. The formation of ED Ni-P amorphous alloys is proposed to consist of nucleation and growth of the amorphous nanograins 20 . The structural model 37 of nanostructured amorphous alloys assumes amorphous nano-grains regions and the interface regions between the nano-grains.…”

“…In this paper, we demonstrate that Ni 82 P 18 amorphous alloys, prepared using multi-phase pulsed ED within a specific pulse current range 20 , have a unique structure factor: for the second peak maximum, there are two sub-peaks with comparable diffraction intensities. The ED Ni 82 P 18 amorphous alloys consist of the following two kinds of amorphous structural components: nanometer-sized regions with solid-like structure (SLS, the atomic structure of melt-quenched MG-like Ni 82 P 18 ) and nanometer-sized regions with liquid-like structure (LLS, of loosepacking compared to a melt-quenched Ni-P ribbon sample).…”

“…Ni 82 P 18 amorphous alloys with a nanometer-sized microstructure (called ED Ni 82 P 18 alloys), characterized by two subpeaks in the second maximum of structure factor, can be prepared by changing the pulse current density based on ED (Supplementary Fig. 1) 20,23,43 . The ED Ni 82 P 18 alloys were found to contain LLSs with abundant loosely packed regions of increased free volume.…”

“…1 shows the structure factor patterns for different alloys prepared using different current densities. For additional details, we refer to Guo et al 20 . MG Ni 82 P 18 ribbons with the same composition as ED Ni 82 P 18 alloys were prepared using melt-spinning with a wheel speed of~30 m s −1 under high-purity argon atmosphere, on to a single copper wheel at 4000 r.p.m.…”

“…The ED amorphous alloys, e.g., the iron-group alloys 17 , which are similar to thermally synthesized alloys in structure, have been widely used in electronics applications, such as in computers, space technology, and energy storage devices, due to their attractive magnetic, mechanical, and chemical properties [16][17][18][19] . Pulsed ED has been successfully used to prepare Ni-P amorphous alloys 20,21 . The reported ED Ni-P amorphous alloys possessed similar diffraction patterns 22,23 as that of the MGs but showed nanoscale structure inhomogeneity.…”