| 초록 |
Electrochemical energy conversion has been expected to play a decisive role in the future energy landscape due to its high efficiency with potential scalability/reversibility. Noble metals, e.g. Pt, have been demonstrated promising catalytic activities in various important reactions such as oxygen reduction reactions, but their high cost and scarcity have limited widespread applications of the devices, remaining on-going challenges in development of catalysts free from noble metals. In this regard, non-precious metal catalysts, typically involving Fe-/N-species anchored on carbon substrates (Fe-N-C), have been made a great progress in their catalytic performance to date. Compared to the considerable attentions in activity, however instability of Fe-N-C has hitherto been much less investigated. In this study, degradation mechanisms of Fe-N-C has been investigated employing operando spectroscopic analysis: online inductively coupled plasma mass spectrometry and differential electrochemical mass spectroscopy in combination with scanning flow cells. The advanced analytical technologies measured real-time Fe demetallation and carbon corrosion along with simultaneous electrochemical operations. Various strategies for stable operations of Fe-N-C were further suggested. |
