Figure 7From: Effects of cobalt precursor on pyrolyzed carbon-supported cobalt-polypyrrole as electrocatalyst toward oxygen reduction reactionXPS spectra for N1s core-level peaks in Co-PPy-TsOH/C catalysts prepared from various cobalt precursors. (a) Cobalt acetate; (b) cobalt nitrate; (c) cobalt oxalate; (d) cobalt chloride.Back to article page