Journal ArticleDOI
Iron-based catalysts with improved oxygen reduction activity in polymer electrolyte fuel cells.
TLDR
In this paper, a microporous carbon-supported iron-based catalysts with active sites believed to contain iron cations coordinated by pyridinic nitrogen functionalities in the interstices of graphitic sheets within the micropores was produced.Abstract:
Iron-based catalysts for the oxygen-reduction reaction in polymer electrolyte membrane fuel cells have been poorly competitive with platinum catalysts, in part because they have a comparatively low number of active sites per unit volume. We produced microporous carbon-supported iron-based catalysts with active sites believed to contain iron cations coordinated by pyridinic nitrogen functionalities in the interstices of graphitic sheets within the micropores. We found that the greatest increase in site density was obtained when a mixture of carbon support, phenanthroline, and ferrous acetate was ball-milled and then pyrolyzed twice, first in argon, then in ammonia. The current density of a cathode made with the best iron-based electrocatalyst reported here can equal that of a platinum-based cathode with a loading of 0.4 milligram of platinum per square centimeter at a cell voltage of >/=0.9 volt.read more
Citations
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Journal ArticleDOI
Hollow nitrogen-doped carbon spheres as efficient and durable electrocatalysts for oxygen reduction
TL;DR: The hollow nitrogen-doped carbon spheres catalysts exhibited ORR activity comparable with a commercial Pt/C catalyst and superior stability in alkaline electrolyte medium.
Journal ArticleDOI
Molecular engineered nanomaterials for catalytic hydrogen evolution and oxidation
TL;DR: Key elements of bio-inspiration are showcased before embarking on a tour of a representative series of molecular hydrogen evolving catalysts and describing the toolbox available for benchmarking their performances and demonstrating the optimization required for implementing molecular-engineered materials into operational devices.
Journal ArticleDOI
Interconnected Hierarchically Porous Fe, N-Codoped Carbon Nanofibers as Efficient Oxygen Reduction Catalysts for Zn-Air Batteries.
TL;DR: Benefiting from the improved mass transfer and utilization of active sites attributed to interconnected hierarchical porous structures, HP-Fe-N/CNFs display excellent ORR catalytic activity in alkaline media, with a comparable onset potential and half-wave potential but superior selectivity, stability, and tolerance against methanol to commercial 30 wt % Pt/C.
Journal ArticleDOI
Dispersing Pt atoms onto nanoporous gold for high performance direct formic acid fuel cells
Rongyue Wang,Jianguo Liu,Pan Liu,Xuanxuan Bi,Xiuling Yan,Wenxin Wang,Xingbo Ge,Xingbo Ge,Mingwei Chen,Yi Ding +9 more
TL;DR: In this article, a molecular self-assembly/electro-deposition process is used to spread Pt atoms onto the surface of a nanoporous gold substrate, and the resulting nanocomposites demonstrate superior electrocatalytic performance toward formic acid electrooxidation, which can be attributed to a nearly ideal catalyst configuration where all the Pt atoms are involved in a highly desired direct reaction path.
Journal ArticleDOI
Exploring the active sites of nitrogen-doped graphene as catalysts for the oxygen reduction reaction
Wenpeng Ouyang,Dongrong Zeng,Xiang Yu,Fangyan Xie,Weihong Zhang,Jian Chen,Jing Yan,Fangjing Xie,Lei Wang,Hui Meng,Dingsheng Yuan +10 more
TL;DR: In this paper, Nitrogen-doped graphene is studied as a kind of nonnoble metal catalyst for the oxygen reduction reaction in the cathode of fuel cells, and the defect of graphene caused by nitrogen doping is detected by Raman spectra.
References
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Journal ArticleDOI
Activity benchmarks and requirements for Pt, Pt-alloy, and non-Pt oxygen reduction catalysts for PEMFCs
TL;DR: In this article, the authors quantified the activities and voltage loss modes for state-of-the-art MEAs (membrane electrode assemblies), specifies performance goals needed for automotive application, and provides benchmark oxygen reduction activities for state of the art platinum electrocatalysts.
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A class of non-precious metal composite catalysts for fuel cells
Rajesh Bashyam,Piotr Zelenay +1 more
TL;DR: The results of this study show that heteroatomic polymers can be used not only to stabilize the non-precious metal in the acidic environment of the PEFC cathode but also to generate active sites for oxygen reduction reaction.
Journal ArticleDOI
A New Fuel Cell Cathode Catalyst
TL;DR: The use of metal phthalocyanines as catalysts for the oxidation of organic compounds has been described in the literature as mentioned in this paper, and a number of these reports were tested as cathode catalysts in fuel cells.
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Dependence of PEM fuel cell performance on catalyst loading
TL;DR: In this paper, a determination of the cell voltage losses observed for Pt and PtRu loading reductions in H2/air and reformate/air polymer/electrolyte-membrane fuel cells (PEMFC) is presented.
Journal ArticleDOI
Heat-treated polyacrylonitrile-based catalysts for oxygen electroreduction
TL;DR: In this paper, a polyacrylonitrile (PAN) mixed with Co(II) or Fe(2) salts and high-area carbon and then heat treated, has been found to yield very promising catalysts for O2 reduction in concentrated alkaline and acid solutions.