Exposed N and S Active Sites: An Indicator for Oxygen Reduction on Metal-Free Yam-Derived Porous Carbons

2017 ◽  
Vol 4 (12) ◽  
pp. 3156-3162 ◽  
Author(s):  
Hao Fan ◽  
Zhen Dong ◽  
Jianshe Zhao
Keyword(s):  
Oxygen Reduction ◽  
Active Sites ◽  
Porous Carbons ◽  
Metal Free

Metal–organic framework templated nitrogen and sulfur co-doped porous carbons as highly efficient metal-free electrocatalysts for oxygen reduction reactions

2014 ◽  
Vol 2 (18) ◽  
pp. 6316-6319 ◽  
Author(s):  
Jisen Li ◽  
Yuyun Chen ◽  
Yujia Tang ◽  
Shunli Li ◽  
Huiqing Dong ◽  
...  
Keyword(s):  
Porous Material ◽  
Oxygen Reduction ◽  
Metal Organic Framework ◽  
Porous Carbons ◽  
Oxygen Reduction Reactions ◽  
Metal Free ◽  
Highly Efficient ◽  
Metal Organic ◽  
Orr Activity ◽  
Co Doped

A novel MOF-templated nitrogen and sulphur co-doped porous material has been first synthesized. The representative NS(3 : 1)–C-MOF-5 shows high ORR activity, even comparable to commercial Pt–C.

scholarly journals Migration-Prevention Strategy to Fabricate Single-Atom Fe Implanted N-Doped Porous Carbons for Efficient Oxygen Reduction

Research ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Dong-Li Meng ◽  
Chun-Hui Chen ◽  
Jun-Dong Yi ◽  
Qiao Wu ◽  
Jun Liang ◽  
...  
Keyword(s):  
Oxygen Reduction ◽  
Active Sites ◽  
Carbonaceous Material ◽  
Nitrogen Sources ◽  
Reduction Reaction ◽  
Prevention Strategy ◽  
Alkaline Media ◽  
Single Atom ◽  
Porous Carbons ◽  
Iron Species

It is highly desired but challenging to achieve highly active single-atom Fe sites from iron-based metal-organic frameworks (MOFs) for efficient oxygen reduction reaction (ORR) due to the easy aggregation of iron species and formation of the inactive Fe-based particles during pyrolysis. Herein, a facile migration-prevention strategy is developed involving the incorporation of polyaniline (PANI) into the pores of iron porphyrinic-based MOF PCN-224(Fe) and followed by pyrolysis to obtain the single-atom Fe implanted N-doped porous carbons material PANI@PCN-224(Fe)-900. The introduced PANI inside the pores of PCN-224(Fe) not only served as protective fences to prevent the aggregation of the iron species during thermal annealing, but also acted as nitrogen sources to increase the nitrogen content and form Fe-Nx-C active sites. Compared with the pristine PCN-224(Fe) derived carbonization sample containing Fe-based particles, the carbonaceous material PANI@PCN-224(Fe)-900 without inactive Fe-based particles exhibited superb ORR electrocatalytic activity with a more positive half-wave potential, significantly improved stability in both alkaline media, and more challenging acidic condition. The migration-prevention strategy provides a new way to fabricate atomically dispersed metal active sites via pyrolysis approach for promoting catalysis.

scholarly journals Identification of catalytic sites for oxygen reduction and oxygen evolution in N-doped graphene materials: Development of highly efficient metal-free bifunctional electrocatalyst

2016 ◽  
Vol 2 (4) ◽  
pp. e1501122 ◽  
Author(s):  
Hong Bin Yang ◽  
Jianwei Miao ◽  
Sung-Fu Hung ◽  
Jiazang Chen ◽  
Hua Bing Tao ◽  
...  
Keyword(s):  
Energy Conversion ◽  
Oxygen Reduction ◽  
Oxygen Evolution ◽  
Active Sites ◽  
Carbon Nanomaterials ◽  
Specific Capacity ◽  
Open Circuit ◽  
Practical Significance ◽  
Metal Free ◽  
Highly Efficient

Oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are critical to renewable energy conversion and storage technologies. Heteroatom-doped carbon nanomaterials have been reported to be efficient metal-free electrocatalysts for ORR in fuel cells for energy conversion, as well as ORR and OER in metal-air batteries for energy storage. We reported that metal-free three-dimensional (3D) graphene nanoribbon networks (N-GRW) doped with nitrogen exhibited superb bifunctional electrocatalytic activities for both ORR and OER, with an excellent stability in alkaline electrolytes (for example, KOH). For the first time, it was experimentally demonstrated that the electron-donating quaternary N sites were responsible for ORR, whereas the electron-withdrawing pyridinic N moieties in N-GRW served as active sites for OER. The unique 3D nanoarchitecture provided a high density of the ORR and OER active sites and facilitated the electrolyte and electron transports. As a result, the as-prepared N-GRW holds great potential as a low-cost, highly efficient air cathode in rechargeable metal-air batteries. Rechargeable zinc-air batteries with the N-GRW air electrode in a two-electrode configuration exhibited an open-circuit voltage of 1.46 V, a specific capacity of 873 mAh g−1, and a peak power density of 65 mW cm−2, which could be continuously charged and discharged with an excellent cycling stability. Our work should open up new avenues for the development of various carbon-based metal-free bifunctional electrocatalysts of practical significance.

Facile potentiostatic preparation of functionalized polyterthiophene-anchored graphene oxide as a metal-free electrocatalyst for the oxygen reduction reaction

2015 ◽  
Vol 3 (10) ◽  
pp. 5426-5433 ◽  
Author(s):  
M. Halappa Naveen ◽  
Hui-Bog Noh ◽  
Md Shahriar Al Hossain ◽  
Jung Ho Kim ◽  
Yoon-Bo Shim
Keyword(s):  
Graphene Oxide ◽  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Active Sites ◽  
Reduction Reaction ◽  
Metal Free

A new polyterthiophene-anchored GO electrocatalyst was prepared. The C–N bonds of the polymer served as active sites for the ORR catalyst.

ZIF-derived in situ nitrogen-doped porous carbons as efficient metal-free electrocatalysts for oxygen reduction reaction

2014 ◽  
Vol 7 (1) ◽  
pp. 442-450 ◽  
Author(s):  
Peng Zhang ◽  
Fang Sun ◽  
Zhonghua Xiang ◽  
Zhigang Shen ◽  
Jimmy Yun ◽  
...  
Keyword(s):  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Reduction Reaction ◽  
Porous Carbons ◽  
Nitrogen Doped ◽  
Metal Free

Heteroatom-doped hierarchical porous carbons as high-performance metal-free oxygen reduction electrocatalysts

2015 ◽  
Vol 3 (22) ◽  
pp. 11725-11729 ◽  
Author(s):  
Yun-Pei Zhu ◽  
Youlin Liu ◽  
Yu-Ping Liu ◽  
Tie-Zhen Ren ◽  
Gao-Hui Du ◽  
...  
Keyword(s):  
Oxygen Reduction ◽  
High Activity ◽  
High Performance ◽  
Porous Carbons ◽  
Free Oxygen ◽  
Metal Free ◽  
Hierarchical Porous ◽  
Hierarchical Porous Carbons ◽  
Electrochemical Oxygen

Heteroatom-doped porous carbons synthesized through a universal polymerization–carbonization protocol exhibit considerable high activity and stability towards electrochemical oxygen reduction.

Template-free synthesis of polyacrylonitrile-derived porous carbon nanoballs on graphene for efficient oxygen reduction in zinc–air batteries

2021 ◽  
Vol 9 (15) ◽  
pp. 9644-9654
Author(s):  
Halima Begum ◽  
Mohammad Shamsuddin Ahmed ◽  
Seunghun Jung
Keyword(s):  
Fuel Cells ◽  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Porous Carbon ◽  
Active Sites ◽  
Reduction Reaction ◽  
Metal Free ◽  
Template Free ◽  
Energy Conversion Devices ◽  
Zinc Air Batteries

Introducing abundant active sites and improving their activity are two critical considerations for designing metal-free nitrogenous electrocatalysts for the oxygen reduction reaction (ORR) in energy conversion devices such as metal–air batteries and fuel cells.

Nitrogen-doped 3D porous carbons with iron carbide nanoparticles encapsulated in graphitic layers derived from functionalized MOF as an efficient noble-metal-free oxygen reduction electrocatalysts in both acidic and alkaline media

RSC Advances ◽  
2016 ◽  
Vol 6 (112) ◽  
pp. 110820-110830 ◽  
Author(s):  
Juanhong Xue ◽  
Ling Zhao ◽  
Zhiyu Dou ◽  
Yan Yang ◽  
Yue Guan ◽  
...  
Keyword(s):  
Oxygen Reduction ◽  
Noble Metal ◽  
Iron Carbide ◽  
Alkaline Media ◽  
Alkaline Solutions ◽  
Porous Carbons ◽  
Free Oxygen ◽  
Nitrogen Doped ◽  
Metal Free ◽  
Acidic And Alkaline Media

Functionalized 3D porous carbons comprising encased iron carbide species, derived from a MOF, display outstanding ORR performance in both acidic and alkaline solutions.

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