Evaluation of NiAl LDH, Al(OH)3, and Zn(OH)2nanoparticle-based coating on nickel foam for hydrogen evolution from aqueous solution

Developing high-performance electrocatalysts for the large-scale hydrogen evolution reaction via electrochemical water splitting is essential. In this research, nickel-aluminum-zinc nanoparticles were deposited onto three-dimensional nickel foam (NiAlZn/NF) using a hydrothermal method. The structure and morphology of the synthesized electrocatalyst were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The crystalline nature was studied using high-resolution transmission electron microscopy (HRTEM). Also, the activity of the hydrogen evolution reaction was investigated using linear scanning voltammetry (LSV) in a 1 M potassium hydroxide (KOH) electrolyte. The coated samples were compared with the bare nickel foam substrate. The results showed the potentials required to create a current density of 10 and 100 mA/cm2 for the 3Ni-4Al-1Zn specimen deposited on nickel foam are 196 and 479 mV, and for the 4Ni-3Al-1Zn are 233 and 484 mV, and for the 3Ni-3Al-1Zn, are 218 and 587 mV, and for the raw nickel foam, are 251 and 624 mV, respectively. Also, the electrochemical impedance spectroscopy (EIS) showed that the value of Rct for 3Ni4Al1Zn, 4Ni3Al1Zn, 3Ni3Al1Zn, and nickel foam is 6.4, 10.2, 18, and 22.1 Ω, respectively. Besides, 3Ni4Al1Zn/NF also shows long-term stability lasting six hours. The Rct value for the 3Ni4Al1Zn sample is lower than the rest, which indicates a better charge transfer during the electrochemical process. The results showed that the coated specimens performed better catalytic behavior in hydrogen generation than the bare nickel foam sample.