Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Highly efficient oxygen reduction electrocatalysts based on winged carbon nanotubes.

ABSTRACT: Developing electrocatalysts with both high selectivity and efficiency for the oxygen reduction reaction (ORR) is critical for several applications including fuel cells and metal-air batteries. In this work we developed high performance electrocatalysts based on unique winged carbon nanotubes. We found that the outer-walls of a special type of carbon nanotubes/nanofibers, when selectively oxidized, unzipped and exfoliated, form graphene wings strongly attached to the inner tubes. After doping with nitrogen, the winged nanotubes exhibited outstanding activity toward catalyzing the ORR through the four-electron pathway with excellent stability and methanol/carbon monoxide tolerance. While the doped graphene wings with high active site density bring remarkable catalytic activity, the inner tubes remain intact and conductive to facilitate electron transport during electrocatalysis.

SUBMITTER: Cheng Y

PROVIDER: S-EPMC3824170 | biostudies-other | 2013

REPOSITORIES: biostudies-other

ACCESS DATA

Json Xml

Publications

Highly efficient oxygen reduction electrocatalysts based on winged carbon nanotubes.

Cheng Yingwen Y Zhang Hongbo H Varanasi Chakrapani V CV Liu Jie J

Scientific reports 20131112

Developing electrocatalysts with both high selectivity and efficiency for the oxygen reduction reaction (ORR) is critical for several applications including fuel cells and metal-air batteries. In this work we developed high performance electrocatalysts based on unique winged carbon nanotubes. We found that the outer-walls of a special type of carbon nanotubes/nanofibers, when selectively oxidized, unzipped and exfoliated, form graphene wings strongly attached to the inner tubes. After doping wit ...[more]

PMID: 24217312

Similar Datasets

Graphdiyne and Nitrogen-Doped Graphdiyne Nanotubes as Highly Efficient Electrocatalysts for Oxygen Reduction Reaction.

Project description:Electrocatalysts with high efficiency and low cost are always urgently needed for oxygen reduction reaction (ORR). As a new carbon allotrope, graphdiyne (GDY) has received much attention due to its unique chemical structure containing sp- and sp2-hybridized carbons, and intrinsic electrochemical activity ascribed to its inherent conductivity. Herein, we prepared two graphdiyne materials named GDY nanotube and nitrogen-doped GDY (NGDY) nanotube via cross-coupling reactions on the surface of Cu nanowires. As metal-free catalysts, their electrocatalytic activities for ORR were demonstrated. The results showed that the NGDY nanotube presents more excellent electrochemical performance than that of the GDY nanotube, including more positive potential and faster kinetics and charge transfer process. The improvement can be ascribed to the greater number of structural electrocatalytic active sites from nitrogen atoms as well as the hollow nanotube morphology, which is beneficial to the adsorption of oxygen and acceleration of the catalytic reaction. This work helps develop high-quality graphdiyne-based electrocatalysts with well-defined chemical structures and morphologies for various electrochemical reactions.

| S-EPMC10706831 | biostudies-literature

Fe@N-Graphene Nanoplatelet-Embedded Carbon Nanofibers as Efficient Electrocatalysts for Oxygen Reduction Reaction.

Project description:An activated carbon nanofiber (CNF) is prepared with incorporated Fe-N-doped graphene nanoplatelets (Fe@NGnPs), via a novel and simple synthesis approach. The activated CNF-Fe@NGnP catalysts exhibit substantially improved activity for the oxygen reduction reaction compared to those of commercial carbon blacks and Pt/carbon catalysts.

| S-EPMC5049621 | biostudies-literature

Carbon-Based Electrocatalysts Derived From Biomass for Oxygen Reduction Reaction: A Minireview.

Project description:Oxygen reduction reaction (ORR) electrocatalysts derived from biomass have become one of the research focuses in hetero-catalysis due to their low cost, high performance, and reproducibility properties. Related researches are of great significance for the development of next-generation fuel cells and metal-air batteries. Herein, the preparation methods of various biomass-derived catalysts and their performance in alkaline, neutral, and acidic media are summarized. This review clarifies the research progress of biomass carbon-based electrocatalysts for ORR in acidic, alkaline and neutral media, and discusses the future development trends. This minireview can give us an important enlightenment to practical application in the future.

| S-EPMC7059099 | biostudies-literature

Sponge-like N-doped carbon materials with Co-based nanoparticles derived from biomass as highly efficient electrocatalysts for the oxygen reduction reaction in alkaline media.

Project description:The development of highly efficient and low-cost catalysts towards Oxygen Reduction Reaction (ORR) is of significance for renewable energy technologies such as proton-exchange membrane fuel cells and metal-air batteries. This study is to utilize the biomass of soybean straw as the supporting carbon materials to prepare nitrogen and cobalt dual-doped porous biocarbon electrocatalysts (CoNASS) possessing high content of N (1.92%), embedding cobalt nanoparticles and sponge-like structure with high specific surface area (1185.00 m2 g-1) as well as appropriate pore diameter (∼2.17 nm). Meantime, CoNASS exhibits a good electrocatalytic activity with a half-wave potential of 0.786 V (vs. RHE), comparable to a half-wave potential of 0.827 V (vs. RHE) for the commercial Pt/C. The detections of electrochemical kinetics show the electron transfer number of CoNASS is in the range of 3.84-3.92, which indicates 4-electron pathway dominantly occurs in ORR. And the limiting diffusion current density of CoNASS at 1600 rpm is around 5.8 mA cm-2 slightly higher than that of the benchmark Pt/C (5.6 mA cm-2). This work opens a new avenue to utilize soybean straw, one of agriculture waste of large quantity, to prepare high efficient and low-cost catalysts for ORR.

| S-EPMC9060698 | biostudies-literature

Zinc-Mediated Template Synthesis of Hierarchical Porous N-Doped Carbon Electrocatalysts for Efficient Oxygen Reduction.

Project description:The development of highly active and low-cost catalysts for use in oxygen reduction reaction (ORR) is crucial to many advanced and eco-friendly energy techniques. N-doped carbons are promising ORR catalysts. However, their performance is still limited. In this work, a zinc-mediated template synthesis strategy for the development of a highly active ORR catalyst with hierarchical porous structures was presented. The optimal catalyst exhibited high ORR performance in a 0.1 M KOH solution, with a half-wave potential of 0.89 V vs. RHE. Additionally, the catalyst exhibited excellent methanol tolerance and stability. After a 20,000 s continuous operation, no obvious performance decay was observed. When used as the air-electrode catalyst in a zinc-air battery (ZAB), it delivered an outstanding discharging performance, with peak power density and specific capacity as high as 196.3 mW cm-2 and 811.5 mAh gZn-1, respectively. Its high performance and stability endow it with potential in practical and commercial applications as a highly active ORR catalyst. Additionally, it is believed that the presented strategy can be applied to the rational design and fabrication of highly active and stable ORR catalysts for use in eco-friendly and future-oriented energy techniques.

| S-EPMC10254328 | biostudies-literature

Hydrogel-derived non-precious electrocatalysts for efficient oxygen reduction.

Project description:The development of highly active, cheap and robust oxygen reduction reaction (ORR) electrocatalysts to replace precious metal platinum is extremely urgent and challenging for renewable energy devices. Herein we report a novel, green and especially facile hydrogel strategy to construct N and B co-doped nanocarbon embedded with Co-based nanoparticles as an efficient non-precious ORR catalyst. The agarose hydrogel provides a general host matrix to achieve a homogeneous distribution of key precursory components including cobalt (II) acetate and buffer salts, which, upon freeze-drying and carbonization, produces the highly active ORR catalyst. The gel buffer containing Tris base, boric acid and ethylenediaminetetraacetic acid, commonly adopted for pH and ionic strength control, plays distinctively different roles here. These include a green precursor for N- and B-doping, a salt porogen and a Co(2+) chelating agent, all contributing to the excellent ORR activity. This hydrogel-based process is potentially generalizable for many other catalytic materials.

| S-EPMC4486930 | biostudies-literature

Unusual high oxygen reduction performance in all-carbon electrocatalysts.

Project description:Carbon-based electrocatalysts are more durable and cost-effective than noble materials for the oxygen reduction reaction (ORR), which is an important process in energy conversion technologies. Heteroatoms are considered responsible for the excellent ORR performance in many carbon-based electrocatalysts. But whether an all-carbon electrocatalyst can effectively reduce oxygen is unknown. We subtly engineered the interfaces between planar graphene sheets and curved carbon nanotubes (G-CNT) and gained a remarkable activity/selectivity for ORR (larger current, and n = 3.86, ~93% hydroxide + ~7% peroxide). This performance is close to that of Pt; and the durability is much better than Pt. We further demonstrate the application of this G-CNT hybrid as an all-carbon cathode catalyst for lithium oxygen batteries.We speculate that the high ORR activity of this G-CNT hybrid stems from the localized charge separation at the interface of the graphene and carbon nanotube, which results from the tunneling electron transfer due to the Fermi level mismatch on the planar and curved sp(2) surfaces. Our result represents a conceptual breakthrough and pioneers the new avenues towards practical all-carbon electrocatalysis.

| S-EPMC4164027 | biostudies-literature

Hemoglobin-carbon nanotube derived noble-metal-free Fe5C2-based catalyst for highly efficient oxygen reduction reaction.

Project description:High performance non-precious cathodic catalysts for oxygen reduction reaction (ORR) are vital for the development of energy materials and devices. Here, we report an noble metal free, Fe5C2 nanoparticles-studded sp(2) carbon supported mesoporous material (CNTHb-700) as cathodic catalyst for ORR, which was prepared by pyrolizing the hybrid adduct of single walled carbon nanotubes (CNT) and lyophilized hemoglobin (Hb) at 700?°C. The catalyst shows onset potentials of 0.92?V in 0.1?M HClO4 and in 0.1?M KOH which are as good as commercial Pt/C catalyst, giving very high current density of 6.34 and 6.69?mA cm(-2) at 0.55?V vs. reversible hydrogen electrode (RHE), respectively. This catalyst has been confirmed to follow 4-electron mechanism for ORR and shows high electrochemical stability in both acidic and basic media. Catalyst CNTHb-700 possesses much higher tolerance towards methanol than the commercial Pt/C catalyst. Highly efficient catalytic properties of CNTHb-700 could lead to fundamental understanding of utilization of biomolecules in ORR and materialization of proton exchange membrane fuel cells for clean energy production.

| S-EPMC4738279 | biostudies-literature

Highly Efficient Oxygen Reduction N-Doped Carbon Nanosheets Were Prepared by Hydrothermal Carbonization.

Project description:A metal-free carbon catalyst is a kind of oxygen reduction catalyst with great prospects. It is an important material with potential to replace the traditional Pt catalyst. In this paper, a kind of irregular and ultra-thin carbon nanosheet (K180M-300-900) with high catalytic activity was synthesized by hydrothermal calcination using okra as a biomass and NH4Cl as an N source. The prepared nitrogen-doped metal-free catalyst with high pyridine-N and graphitic-N provides an extremely large number of active sites and has certain lattice defects. Ultra-thin carbon nanosheets promote sufficient contact between the catalyst and electrolyte, promote the diffusion of oxygen, and result in a faster transfer rate of electrons. The initial potential and half-slope potential of K180M-300-900 are 0.99 V and 0.82 V, respectively, which are comparable to those of 20% Pt/C. In addition, the stability and methanol tolerance of this catalyst (K180M-300-900) are better than 20% Pt/C, so it has great development potential and application value. This result provides a new method to prepare metal-free carbon materials that will take the place of traditional Pt catalysts.

| S-EPMC10780226 | biostudies-literature

Polydopamine-coated graphene nanosheets as efficient electrocatalysts for oxygen reduction reaction.

Project description:Polydopamine-modified graphene (G-PDA) materials were synthesized by in situ polymerization of a dopamine monomer on the surface of graphene oxide. X-ray photoelectron spectroscopy (XPS) has confirmed that new N-containing functional groups are formed during the synthesis process, which result in the excellent electrocatalytic activity of the composite towards ORR in terms of onset potential, number of electron transferred and limiting current density. The electrocatalytic activity of the optimized G-PDA sample is better than N-doped graphene and comparable to the commercial 20 wt% Pt/C catalyst. Furthermore, compared with the Pt-based catalysts, the G-PDA showed superior stability and methanol resistance, which favored its practical applications in fuel cells.

| S-EPMC9080247 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data