A mesoporous carbon-based catalyst derived from cobalt and boron co-doped melamine formaldehyde gel for oxygen reduction reaction

Effect of Nitrogen-Containing Carbon Shell-Coated Carbon Support on the Catalytic Performance of Platinum–Cobalt Alloy Catalyst for Oxygen Reduction

“…Figure a shows that the large broad peak at approximately 2θ = 25° corresponds to the (002) plane of graphitic carbon and the small peak at 2θ = 44° corresponds to the (101) plane. The existence of these two peaks indicates that these C@NC contain turbostratic graphitic carbon structures, which are composed of two-dimensional long-range ordered graphitic carbon structures and amorphous carbon structures Figure a shows that as the calcination temperature increases from 600 to 900 °C, the (101) peak intensity of the C@NC first decreased and then increased.…”

“…The existence of these two peaks indicates that these C@NC contain turbostratic graphitic carbon structures, which are composed of two-dimensional longrange ordered graphitic carbon structures and amorphous carbon structures. 26 Figure 3a shows that as the calcination temperature increases from 600 to 900 °C, the (101) peak intensity of the C@NC first decreased and then increased. The minimum value is reached at 700 °C, which indicates that the amorphous carbon content in the C@NC-700 is the largest when the calcination temperature is 700 °C.…”

The effect of nitrogen species on the catalytic properties of N-doped graphene

“…Effective electrocatalysts in fuel cells 4 , 5 , lithium–air batteries 6 , 7 , and zinc–air batteries 8 , 9 should be active in the oxygen reduction reaction (ORR) 10 – 12 , the key reaction in devices of this sort. Some very promising alternatives to noble-metal electrode materials are carbon materials doped with non-metal heteroatoms, e.g., phosphorus 13 – 15 , boron 14 , 16 or nitrogen 14 , 17 , 18 inserted into the basic carbon structure, of which the most promising catalysts are those containing nitrogen functional groups 19 – 21 , such as pyridine nitrogen (N-6) and pyrrole nitrogen (N-5). At the same time, very high concentrations of heteroatoms and a large amount of defects in the structure can contribute to a decrease in electronic conductivity and disadvantage the oxygen reduction reaction 22 .…”

In Situ Self‐Supporting Cobalt Embedded in Nitrogen‐Doped Porous Carbon as Efficient Oxygen Reduction Electrocatalysts

“…In general, Co-N x /C hybrids are synthesized using the following methods: i) direct-pyrolysis of cobalt-based macrocyclic compounds containing porphyrin, [10] phthalocyanine, [11] and 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ); [12] ii) post-treatment of cobalt salt, carbon and nitrogen source like urea, [13] pyridine [14] and melamine. [15] Ethylenediamine-tetra-acetic acid (EDTA) serves as nitrogen source and chelating agent coordinated with Co II ions, while also acting as a pore builder and creating numerous micropores/mesopores during the thermal pyrolysis thus favoring the exposure of more active sites and accelerating reactants transfer in the electrolyte. [16] In this work, we prepared a series of electrocatalysts of Coembedded in N-doped porous carbon materials (Co@CÀ T) produced by in-situ thermal pyrolysis of Co II /EDTA chelate complex supported on glucose precursor at different temperatures from 500 to 900°C under nitrogen atmosphere, as shown in Figure 1.…”

“…Apart from the intrinsic activities of the active centers, the ORR electrocatalytic performance of M‐N x /C materials is also governed by the specific surface area and porosity of the carbon matrix, which are related to the mass transfer and accessibility of active sites. In general, Co‐N x /C hybrids are synthesized using the following methods: i) direct‐pyrolysis of cobalt‐based macrocyclic compounds containing porphyrin, phthalocyanine, and 2,4,6‐tris(2‐pyridyl)‐1,3,5‐triazine (TPTZ); ii) post‐treatment of cobalt salt, carbon and nitrogen source like urea, pyridine and melamine . Ethylene‐diamine‐tetra‐acetic acid (EDTA) serves as nitrogen source and chelating agent coordinated with Co II ions, while also acting as a pore builder and creating numerous micropores/mesopores during the thermal pyrolysis thus favoring the exposure of more active sites and accelerating reactants transfer in the electrolyte …”