Core Level Shifts of Hydrogenated Pyridinic and Pyrrolic Nitrogen in the Nitrogen-Containing Graphene-Based Electrocatalysts: In-Plane vs. Edge Defects was written by Matanovic, Ivana;Artyushkova, Kateryna;Strand, Matthew B.;Dzara, Michael J.;Pylypenko, Svitlana;Atanassov, Plamen. And the article was included in Journal of Physical Chemistry C in 2016.Computed Properties of C5H6ClN This article mentions the following:
A combination of N 1s XPS and 1st principles calculations of N-containing model electrocatalysts was used to elucidate the nature of the N defects that contribute to the binding energy (BE) range of the N 1s XPS spectra of these materials ≳400 eV. Exptl. core level shifts were obtained for a set of model materials, N-doped C nanospheres, Fe-N-C nanospheres, polypyrrole, polypyridine, and pyridinium chloride, and were compared to the shifts calculated using d. functional theory. The broad peak positioned at ∼400.7 eV in the N 1s XPS spectra of N-containing catalysts, which is typically assigned to pyrrolic N, contains contributions from other hydrogenated N species such as hydrogenated pyridinic functionalities. Namely, N 1s BEs of hydrogenated pyridinic-N and pyrrolic-N were calculated as 400.6 and 400.7 eV, resp., using the Perdew-Burke-Ernzerhof exchange-correlation functional. A special emphasis was placed on the study of the differences in the XPS imprint of N-containing defects that are situated in the plane and on the edges of the graphene sheet. D. functional theory calculations for BEs of the N 1s of in-plane and edge defects show that hydrogenated N defects are more sensitive to the change in the chem. environment in the C matrix than the nonhydrogenated N defects. Calculations also show that edge-hydrogenated pyridinic-N and pyrrolic-N defects only contribute to the N 1s XPS peak located at ∼400.7 eV if the graphene edges are oxygenated or terminated with bare C atoms. In the experiment, the researchers used many compounds, for example, Pyridinehydrochloride (cas: 628-13-7Computed Properties of C5H6ClN).
Pyridinehydrochloride (cas: 628-13-7) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Computed Properties of C5H6ClN