NiMo Solid Solution Nanowire Array Electrodes for Highly Efficient Hydrogen Evolution Reaction

Abstract

Developing high‐performance noble metal–free electrodes for efficient water electrolysis for hydrogen production is of paramount importance for future renewable energy resources. However, a grand challenge is to tailor the factors affecting the catalytic electrodes such as morphology, structure, and composition of nonprecious metals. Alloying catalytic metals can lead to a synergistic effect for superior electrocatalytic properties. However, alloy formation in solution at low synthesis temperatures may result in better catalytic properties as compared to those at high temperatures due to the controlled reaction kinetics of nucleation and growth mechanisms. Herein, an aqueous solution–based preparation technology is developed to produce NiMo alloy nanowire arrays. The NiMo alloy shows significantly improved hydrogen evolution reaction (HER) catalytic activity, featured with extremely low overpotentials of 17 and 98 mV at 10 and 400 mA cm−2, respectively, in an alkaline medium, which are better than most state‐of‐the‐art non‐noble metal–based catalysts and even comparable to platinum‐based electrodes. Analyses indicate that the lattice distortions induced by Mo incorporation, increased interfacial activity by alloy formation, and plenty of MoNi4 active sites at nanowires surface collectively contribute to remarkably enhanced catalytic activity. This study provides a powerful toolbox for highly efficient nonprecious metal–based electrodes for practical HER application.

Self‐Supporting Ni‐M (M = Mo, Ge, Sn) Alloy Nanosheets via Topotactic Transformation of Oxometallate Intercalated Layered Nickel Hydroxide Salts: Synthesis and Application for Electrocatalytic Hydrogen Evolution Reaction

“…This strict atomic ratio of bivalent and trivalent metal cations in LDHs limits the possible composition of multimetallic alloys. Given the reported excellent HER performance of Ni‐alloys such as NiSn, NiGe, and especially NiMo, there is an urgent need to develop a new method to produce self‐supporting Ni‐alloy nanostructures bypassing the trivalent metal restriction imposed by LDHs. Inspired by the tunable interlayer spacing of layered hydroxide salts (LHS), such as α‐Ni(OH) 2 , through intercalating anions adjustment, we speculate that a second metallic precursor in the form of oxometallate anions may be introduced into the interlayer gallery of LHS, which can then be further reduced to produce Ni‐alloy nanosheets, thus broadening the scope of the emerging LDHs derivatives.…”

Improving plasma sprayed Raney-type nickel–molybdenum electrodes towards high-performance hydrogen evolution in alkaline medium

“…The catalyst at the same time should be cost effective. Currently many scientific reports therefore focus on the development of more efficient and inexpensive HER catalysts for the cathode side to improve the performance of AWE electrolyzer [10][11][12][13] . Several non-precious metal-based materials, such as transition-metal chalcogenides 14 , carbides 15 and metal alloys 16 , have been widely studied and characterized as HER electrodes.…”

Defect Engineering of Molybdenum-Based Materials for Electrocatalysis

“…The performance of the porous Ni-Mo alloy microspheres catalyst could be close to that of Pt/C. Interestingly, Nairan et al reported a NiMo solid solution nanowire array electrode synthesized via a facile magnetic field assisted the growth process [89]. The doping of Mo atoms expanded t5.1.1he lattice of surface atoms (d-band shift), and thus, the intrinsic activity of the metal catalyst was significantly improved.…”