In situ exsolved Co components on wood ear-derived porous carbon for catalyzing oxygen reduction over a wide pH range

2021 ◽  
Author(s):  
Yu Xu ◽  
Haiyan Zhang ◽  
Ping Zhang ◽  
Min Lu ◽  
Xiaoji Xie ◽  
...  
Keyword(s):  
Transition Metal ◽  
Oxygen Reduction ◽  
Porous Carbon ◽  
Active Sites ◽  
Reduction Reaction ◽  
Great Promise ◽  
Wide Ph Range ◽  
Ph Range ◽  
Carbon Catalysts

Carbon-based catalysts with transition metal active sites hold great promise for electrochemically catalyzing oxygen reduction reaction (ORR). However, it is still challenging to fabricate carbon catalysts containing transition metal active...

Mechanism of Oxygen Reduction Reaction on Transition Metal–Nitrogen–Carbon Catalysts: Establishing the Role of Nitrogen-containing Active Sites

2018 ◽  
Vol 1 (11) ◽  
pp. 5948-5953 ◽  
Author(s):  
Yechuan Chen ◽  
Ivana Matanovic ◽  
Elizabeth Weiler ◽  
Plamen Atanassov ◽  
Kateryna Artyushkova
Keyword(s):  
Transition Metal ◽  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Active Sites ◽  
Reduction Reaction ◽  
Carbon Catalysts

scholarly journals Warped graphitic layers generated by oxidation of fullerene extraction residue and its oxygen reduction catalytic activity

2019 ◽  
Vol 10 ◽  
pp. 1391-1400 ◽  
Author(s):  
Machiko Takigami ◽  
Rieko Kobayashi ◽  
Takafumi Ishii ◽  
Yasuo Imashiro ◽  
Jun-ichi Ozaki
Keyword(s):  
Catalytic Activity ◽  
Oxygen Reduction ◽  
Active Sites ◽  
Reduction Reaction ◽  
Oxidation Time ◽  
Pt Catalyst ◽  
Oxidation Treatment ◽  
Orr Activity ◽  
Temperature Programmed ◽  
Carbon Catalysts

Carbon-based oxygen reduction reaction (ORR) catalysts are regarded as a promising candidate to replace the currently used Pt catalyst in polymer electrolyte fuel cells (PEFCs); however, the active sites remain under discussion. We predicted that warped graphitic layers (WGLs) are responsible for the ORR catalytic activity in some carbon catalysts (i.e., carbon alloy catalysts (CACs)). To prove our assumption, we needed to use WGLs consisting of carbon materials, but without any extrinsic catalytic elements, such as nitrogen, iron, or cobalt, which effectively enhance ORR activity. The present study employed a fullerene extraction residue as a starting material to construct WGLs. The oxidation of the material at 600 °C exposed the WGLs by removing the surrounding amorphous moieties. Transmission electron microscopy (TEM) observations revealed the formation of WGLs by oxidation treatment at 600 °C in an O2/N2 stream. Extending the oxidation time increased the purity of the WGL phase, but also simultaneously increased the concentration of oxygen-containing surface functional groups as monitored by temperature programmed desorption (TPD). The specific ORR activity increased with oxidation up to 1 h and then decreased with the intensive oxidation treatment. Correlations between the specific ORR activity and other parameters confirmed that the development of the WGL and the increase in the O/C ratio are the competing factors determining specific ORR activity. These results explain the maximum specific ORR activity after 1 h of oxidation time. WGLs were found to lower the heat of adsorption for O2 and to increase the occurrence of heterogeneous electron transfer.

In situ Fe2N@N-doped porous carbon hybrids as superior catalysts for oxygen reduction reaction

Nanoscale ◽  
2017 ◽  
Vol 9 (24) ◽  
pp. 8102-8106 ◽  
Author(s):  
Xiaoxiao Huang ◽  
Ziyu Yang ◽  
Bing Dong ◽  
Yazhou Wang ◽  
Tianyu Tang ◽  
...  
Keyword(s):  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Porous Carbon ◽  
Reduction Reaction

Preparation of monodisperse ferrous nanoparticles embedded in carbon aerogels via in situ solid phase polymerization for electrocatalytic oxygen reduction

Nanoscale ◽  
2020 ◽  
Vol 12 (28) ◽  
pp. 15318-15324
Author(s):  
Wei Hong ◽  
Xin Feng ◽  
Lianqiao Tan ◽  
Aiming Guo ◽  
Bing Lu ◽  
...  
Keyword(s):  
Oxygen Reduction ◽  
Active Sites ◽  
Solid Phase ◽  
Reduction Reaction ◽  
Carbon Aerogels ◽  
Structured Materials ◽  
Nitrogen Doped ◽  
Electrocatalytic Oxygen Reduction ◽  
Nitrogen Doped Carbon

Core–shell structured materials constructed by using Fe/Fe3C cores and nitrogen doped carbon shells represent a type of promising non-precious oxygen reduction reaction (ORR) catalyst due to well-established active sites at the interface positions.

scholarly journals Recent Advances in Non-Precious Transition Metal/Nitrogen-doped Carbon for Oxygen Reduction Electrocatalysts in PEMFCs

Catalysts ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 141 ◽  
Author(s):  
Meixiu Song ◽  
Yanhui Song ◽  
Wenbo Sha ◽  
Bingshe Xu ◽  
Junjie Guo ◽  
...  
Keyword(s):  
Transition Metal ◽  
Oxygen Reduction ◽  
Active Sites ◽  
Proton Exchange Membrane ◽  
High Efficiency ◽  
Catalytic Performance ◽  
Reduction Reaction ◽  
Proton Exchange ◽  
Nitrogen Doped ◽  
Nitrogen Doped Carbon

The proton exchange membrane fuel cells (PEMFCs) have been considered as promising future energy conversion devices, and have attracted immense scientific attention due to their high efficiency and environmental friendliness. Nevertheless, the practical application of PEMFCs has been seriously restricted by high cost, low earth abundance and the poor poisoning tolerance of the precious Pt-based oxygen reduction reaction (ORR) catalysts. Noble-metal-free transition metal/nitrogen-doped carbon (M–NxC) catalysts have been proven as one of the most promising substitutes for precious metal catalysts, due to their low costs and high catalytic performance. In this review, we summarize the development of M–NxC catalysts, including the previous non-pyrolyzed and pyrolyzed transition metal macrocyclic compounds, and recent developed M–NxC catalysts, among which the Fe–NxC and Co–NxC catalysts have gained our special attention. The possible catalytic active sites of M–NxC catalysts towards the ORR are also analyzed here. This review aims to provide some guidelines towards the design and structural regulation of non-precious M–NxC catalysts via identifying real active sites, and thus, enhancing their ORR electrocatalytic performance.

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