Nitrogen-doped graphene usually have three main peaks, including pyridinic N, pyrrolic N, and quaternary N. Normally, We deconvoluted the XPS N1s spectrum. The binding energy (BE) of pyridinic N and pyrrolic N are at 398.6 and 399.5 eV, respectively. Why the BE of pyrrolic N is higher than that of pyridinic N?
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