A Density Functional Theory Investigation of Ammonia Oxidation on the M-doped β-Ni(OH)2 (M = Cr, Co, Cu, Fe) Surfaces

The ammonia oxidation reaction (AOR) has applications as a sustainable energy source and in wastewater remediation. Nickle based catalysts for the AOR reaction are ideal as they are cost efficient, have longer lifetimes than more expensive alterna- tives, and can produce value-added products. Dopants can be applied to these nickle catalysts to further increase their value. This work explores the effects on reaction potentials when β-Ni(OH)2 is doped with chromium, cobalt, copper, or iron using den- sity functional theory to model the AOR. Limiting potentials for dinitrogen production improved when β-Ni(OH)2 was doped with chromium and cobalt. Limiting potentials for nitrite production remained consistent when the β-Ni(OH)2 was doped with cobalt or iron. Compared to the pristine β-Ni(OH)2 surface, there was no improvement in the limiting potential of nitrate formation for any of the doped surfaces. This research be- gins to unfold the importance of exploring dopant addition to β-Ni(OH)2 as a method of improving the catalysts activity for the AOR.