Spectroscopy of N-doped graphene catalyst surface toward ORR under reaction conditions

Abstract

In this study, in-situ Raman spectroscopy and IR spectroscopy were operated to reveal ORR elementary steps under acidic condition on molecular catalyst containing pyri-N and strongly-hydrophobic. We found the pyri-N was protonated in sulfuric acid before ORR starts. At the same time, hydrogensulfate (HSO₄⁻) adsorbed as a counter anion. DFT calculations also showed these protonation steps and the protonated pyri-N can recierve an electron to form neutral atomic with the application of voltages. These hydrogenation steps could trigger the O₂ adsorption effectively.