Ni-Al layered double hydroxides electrodeposition from a chloride solution

Ni-Al LDHs was electrodeposited from a NiCl2-AlCl3 solution. In order to analyze the electrodeposition process, electrolytes with initial Al content range of 0-20% were used. With increasing Al content in the sample, the preferred orientations of (0 0 3) and (0 0 6), increased crystallinity, and decreased interlayer spacing were observed from the XRD results. A dissolution-re crystallization of (0 0 3) plane was detected among the Ni-Al LDHs from the strongly alkaline solution soaking results, which was found to be conducted easily in high Al-containing samples. The pH of the Al-containing electrolyte was much lower than that of pure NiCl2 solution because lower pH was needed to start a precipitation reaction in the AlCl3-NiCl2 solution. The electrodeposition yield and current efficiency were found to decrease obviously in the electrolytes with initial Al content higher than 10%, which was attributed to the increasing Al content in the sample and diffusion of the complex ions. The electrodeposition pattern was in-situ in the electrolyte initially containing 10% Al, then, it developed toward and off in-situ in electrolytes initially containing 0-10% and 1020% Al. (C) 2021 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

Automated summary

Ni-Al LDHs were electrodeposited from a NiCl2-AlCl3 solution, with variations in the initial Al content in the electrolyte affecting the preferred orientations, crystallinity, and interlayer spacing of the resulting materials. The presence of higher Al content led to decreased electrodeposition yield and current efficiency, attributed to increased Al content and diffusion of complex ions. The electrodeposition pattern evolved from in-situ to off in-situ as the initial Al content in the electrolyte changed.