Interface Engineering of Nite/Nico-Ldh Core-Shell Structure to Enhance Oxygen Evolution Electrocatalysis Performance

Abstract

Non-noble metal-based heterostructures have emerged as a promising strategy to construct high-efficient electrocatalysts for the Oxygen evolution reaction (OER). Herein, we reported a three-dimensional (3D) core-shell heterostructures of NiTe/NiCo-LDH (NiCo layered double hydroxides) on the Ni foam (NF) to resolve the low electronic conductivity and self-aggregation of NiCo-LDH. This NiTe/NiCo-LDH electrocatalyst could be prepared from a two-step reaction as hydrothermal reaction and electrodeposition approach. Benefiting from the existence of strong interface effects between the NiTe nanorod core and NiCo-LDH nanosheet shell, the NiTe/NiCo-LDH electrocatalyst exhibited superior activity for the OER at a current density of 100 mA cm-2 with an overpotential of 376 mV in 1.0 M KOH solution, which was significantly smaller than that of a single component of NiTe (586 mV), NiCo-LDH (410 mV) and commercial RuO2 (428 mV). Furthermore, the NiTe/NiCo-LDH catalyst indicated a long-term stability after 24 h continuous working. Density functional theory (DFT) computations unveil that the heterostructures modified the original electronic structures and weakened the atomic interaction in the LDH layers, which have effectively adjusted the d-band center of the catalytic active Co sites to the Fermi level. This work demonstrated an effective strategy of interfacial engineering to optimize electron transfer to boost OER performance.

Keywords: Interface engineering, NiTe/NiCo-LDH, electrodeposition, low overpotentials, Water splitting