Hard x-ray photoelectron spectroscopy (HAXPES) of bulk nickel hydroxide Ni(OH)2 with Au overlayer

Nickel hydroxide is a key material for batteries, supercapacitors, and electrocatalysis. In this study, hard x-ray photoelectron spectroscopy (HAXPES) using 5951 eV photons was employed to probe deep-core levels of commercial Ni(OH)2 powder with enhanced bulk sensitivity. The Ni 2p and Ni 2s HAXPES spectra are presented, showing characteristic multiplet and satellite features in the Ni 2p region and a significant chemical shift of the Ni 2s peak relative to reported values for metallic Ni.