In situ electron energy loss spectroscopy study of metallic Co and Co oxides

摘要: Determining the Co valence, particularly in Co-based nanocatalysts is a longstanding experimental challenge. In this paper, we utilize situ electron energy-loss spectroscopy and first-principles density functional theory calculations to distinguish between metallic Co, Co3O4, as well CoO. More specifically, differences O K- Co L-edges are utilized determine valence different Co-oxide particles. We will further demonstrate that while Co L3/L2-ratio equals of partially reduced near-edge fine-structure Co L-edge exhibits additional features not present any Co-oxide. The origin these be discussed. Based on our theoretical results, propose fitting method from Co-oxides.