Sulfur-Rich N-Doped Co₉S₈ Catalyst for Highly Efficient and Durable Overall Water Electrolysis Application

Figure 5

(a) XPS survey spectra for the CoS, N-Co₉S₈, and S,N-Co₉S₈ catalyst measured within a binding energy range of 0 and 1400 eV. High-resolution XPS emission spectra: (b) Co 2p, (c) S 2p, and (d) N 1 s for the CoS, N-Co₉S₈, and S,N-Co₉S₈ catalysts. All of these high-resolution XPS spectra were calibrated with the C 1 s peak of the carbon contaminant and deconvoluted using a Gaussian curve fitting model.

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