Nitrogen: unraveling the secret to stable carbon-supported Pt-alloy electrocatalysts

Pt nanoparticles interacting with graphitic nitrogen of N-doped carbon nanotubes: Effect of electronic properties on activity for aerobic oxidation of glycerol and electro-oxidation of CO

“…Density functional theory calculations have been used to explore the bonding between Pt and various nitrogen sites. It was found that Pt atoms bond strongly with pyridinic nitrogen, especially sites containing three pyridinic nitrogens neighboring a carbon vacancy, which may result in increased strength of the metal-support interaction (MSI) [14,18]. However, experimental proofs supporting the preferential adsorption of Pt on specific nitrogen functionalities are still lacking to date.…”

“…Nitrogen dopants endow carbon materials with interesting electronic characteristics and surface chemistry, making nitrogen-doped carbon nanotubes (NCNTs) very attractive candidates as metal-free catalysts [7][8][9] or supports for metals [10][11][12]. Nitrogen atoms incorporated into CNTs can form a variety of functionalities, including quaternary (graphitic), pyridinic, pyrrolic nitrogen, and nitrogen oxides, which act as active sites to anchor metal nanoparticles (NPs) to achieve highly dispersed catalysts [12][13][14][15]. In addition, NPs electronically interact with the nitrogen-containing functionalities, leading to novel catalytic behavior through metal-support and metalsupport-reactant interactions [16][17][18][19].…”

“…Until 2013, direct observation of the spatial relationship between nitrogen functionalities and NPs was achieved by advanced aberration-corrected scanning transmission electron microscopy [14]. However, as one of the most important fundamental issues, it is still under debate which type of nitrogen functionality on NCNTs is responsible for anchoring metallic NPs.…”

Carbon nitrides: synthesis and characterization of a new class of functional materials

“…nitrogen content and the metal nanoparticles that constitute the catalytic centres. 33,34 Wöhler reported a characteristic ''snake-like'' appearance of the voluminous porous solid residue that emerged as the salt was burned in air. 38,39 That remarkable and seemingly magical property later led to the development of pyrotechnic materials that were packaged and sold as ''Pharaoh's serpents'' eggs, following a loose reference to the mystical behavior of Moses' staff.…”

Graphitic Carbon Nitride-Graphene Hybrid Nanostructure as a Catalyst Support for Polymer Electrolyte Membrane Fuel Cells

“…In addition, it was demonstrated that there is a strong "tethering" interaction between Pt nanoparticles and nitrogen atoms, and the N-dopant alters the catalyst electronic structure, leading to an increase in catalytic activity (22)(23)(24)(25). However, such doping strategies can only introduce limited amount of nitrogen in the material (22).…”