Fig. 8

a Overall XPS survey, b Zn peak analysis, c Co2p peak analysis, d O1s peak analysis, e Fe2p peak analysis, f C1s peak analysis for CoF1 sample.
a Overall XPS survey, b Zn peak analysis, c Co2p peak analysis, d O1s peak analysis, e Fe2p peak analysis, f C1s peak analysis for CoF1 sample.