Pyridinic-Type N-Doped Graphene on Cobalt Substrate as Efficient Electrocatalyst for Oxygen Reduction Reaction in Acidic Solution in Fuel Cell

Abstract

In this study, we use density functional theory to investigate the catalytic activity of graphene (G), single vacancy defective graphene (G SV ), quaternary N-doped graphene (NG Q ), and pyridinic N-doped graphene (NG py , 3NG py , and 4NG py ) on Co(0001) substrate for an oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). The results show pyridinic N-doped graphene on a Co support exhibited better performance than the NG Q on a Co support and free-standing systems. According to the results, ORR intermediates (*OOH, *O, and *OH) become more stable due to the presence of a Co substrate. The single pyridinic (3NG py ) layer placed on Co(0001) is the most active site. The overpotential for Co/3NG py is rather higher compared to pure Pt( 111) catalyst (0.65 V). Therefore, pyridinic N-doped graphene with a cobalt support could be a promising strategy to enhance the ORR activity of N-doped graphene in PEMFCs.

Proton Exchange Membrane Fuel Cells (PEMFCs): Advances and Challenges

“…In their structure, the size of the active material determines the specific area, the catalytic activity, and the distance over which a solid-state diffusion process operates, where the size of pores and porosity affect mass transport and ion conduction in the electrolyte. New perspectives on fuel cell technology were analyzed in a recent work to reduce the costs of the membrane and improve cell efficiency, durability and reliability, allowing them to compete with the traditional combustion engine [ 347 ]. Fundamentals of theory and practical operation of a PEMFC involving various mathematical models, quantum mechanics, and DFT studies were performed to support the experimental results [ 217 , 348 , 349 ].…”

Zinc/graphitic carbon nitride co-mediated dual-template synthesis of densely populated Fe–Nx-embedded 2D carbon nanosheets towards oxygen reduction reactions for Zn–air batteries

“…Besides, the pyridinic-N and graphitic-N species are dominated within the N 1s spectra of SAs-Fe/N-CNSs-2, which can increase the current density and facilitate the 4-electron catalytic pathway for ORRs, respectively. [62][63][64] As revealed by the high-resolution Fe 2p spectra, the largest Fe-N percentage of SAs-Fe/N-CNSs-2 among the SAs-Fe/ N-CNSs-x catalysts further manifests the existence of the highest density of Fe-N x moieties within SAs-Fe/N-CNSs-2 (Fig. S8 †).…”

Environmental Technologies to Treat Rare Earth Element Pollution: Principles and Engineering

“…Unfortunately, rapid degradation and slow reaction kinetics substantially reduce the rate of commercialization of low-temperature FCs (Guterman et al, 2009(Guterman et al, , 2014. To mitigate these drawbacks, the following approaches have been tried: forming platinum alloys with d-metals (Gudko et al, 2009;McKeown & Rhen, 2018), control over the NPs size and shape (Chen et al, 2014(Chen et al, , 2020, formation of the core-shell (Alinezhad et al, 2020), Pt-skin or skeleton (Stamenkovic et al, 2006) and yolk (Ao et al, 2018) structures, preparation of PGM-free catalysts like Fe/N/C (Wan et al, 2019), Co/N/C (Haile et al, 2021;Li et al, 2019), Fe/Co/N/C (Lastovina et al, 2018b;Pimonova et al, 2019aPimonova et al, , 2019b, metal-free carbons, transition metal carbides (Guil-López et al, 2010) and nitrides (Abdelkareem et al, 2020) and ternary catalysts (Antolini, 2007).…”