A correction was made to Figs. 5 and 6. The original versions of Figs. 5(b) and 6(b) needed correcting, as the original graphs were missing a second y-axis. The second y-axis has been added, along with a note in the legend, for both figures. The correction serves only as a rectification of a labelling error and does not affect the conclusions of the paper.
(a) XPS of Ni 2p, C 1s, and O 1s and (b) the relative atomic percentage of different nickel chemical states as a function of oxidation time. All experiments started with 15 s Ar sputtering, followed by in situ oxidation at 500 W power and 0 W applied bias.
(a) XPS of Ni 2p, C 1s, and O 1s and (b) the relative atomic percentage of different nickel chemical states as a function of oxidation time. All experiments started with 15 s Ar sputtering, followed by in situ oxidation at 500 W power and 0 W applied bias.
(a) XPS of Ni 2p, C 1s, and O 1 s, and (b) the relative atomic percentage of different nickel chemical states as a function of substrate bias. All experiments started with 15 s Ar sputtering, followed by in situ oxidation at 500 W power for 30 s.
(a) XPS of Ni 2p, C 1s, and O 1 s, and (b) the relative atomic percentage of different nickel chemical states as a function of substrate bias. All experiments started with 15 s Ar sputtering, followed by in situ oxidation at 500 W power for 30 s.
