Browse
Submit Data
Databases
API
Help

Dataset Information

21 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Nitrogen-Doped Ketjenblack Carbon Supported Co₃O₄ Nanoparticles as a Synergistic Electrocatalyst for Oxygen Reduction Reaction.

ABSTRACT: Developing a highly active and cost-effective cathode electrocatalyst with strong stability for oxygen reduction reaction (ORR) is extremely necessary. In this work, we reported a facile synthetic path to prepare a hybrid nanostructure formed of nitrogen-doped Ketjenblack carbon (N-KC) supported Co₃O₄ nanoparticles (Co₃O₄/N-KC), which could be used as a promising and stable electrocatalyst for ORR. Compared with the physical mixture of Co₃O₄ and N-KC and pure N-KC samples, the resulting Co₃O₄/N-KC nanohybrid afforded remarkably superb ORR activity with a half-wave potential of 0.82 V (vs. reversible hydrogen electrode, RHE) and a limiting current density of 5.70 mA cm^-2 in KOH solution (0.1 M). Surprisingly, the Co₃O₄/N-KC sample possessed a similar electrocatalytic activity but better durability to the 20 wt% Pt/C catalyst. The remarkable ORR activity of the Co₃O₄/N-KC nanohybrid was mainly due to the strong coupling effect between Co₃O₄ and N-KC, the N species dopant, high electroconductivity, and the large BET surface area. Our work enlightens the exploitation of advanced Co₃O₄/carbon hybrid material alternative to the Pt-based electrocatalysts.

SUBMITTER: Cheng G

PROVIDER: S-EPMC6904301 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Nitrogen-Doped Reduced Graphene Oxide Supported Pd4.7Ru Nanoparticles Electrocatalyst for Oxygen Reduction Reaction.

Project description:It is imperative to design an inexpensive, active, and durable electrocatalyst in oxygen reduction reaction (ORR) to replace carbon black supported Pt (Pt/CB). In this work, we synthesized Pd4.7Ru nanoparticles on nitrogen-doped reduced graphene oxide (Pd4.7Ru NPs/NrGO) by a facile microwave-assisted method. Nitrogen atoms were introduced into the graphene by thermal reduction with NH3 gas and several nitrogen atoms, such as pyrrolic, graphitic, and pyridinic N, found by X-ray photoelectron spectroscopy. Pyridinic nitrogen atoms acted as efficient particle anchoring sites, making strong bonding with Pd4.7Ru NPs. Additionally, carbon atoms bonding with pyridinic N facilitated the adsorption of O2 as Lewis bases. The uniformly distributed ~2.4 nm of Pd4.7Ru NPs on the NrGO was confirmed by transmission electron microscopy. The optimal composition between Pd and Ru is 4.7:1, reaching -6.33 mA/cm2 at 0.3 VRHE for the best ORR activity among all measured catalysts. Furthermore, accelerated degradation test by electrochemical measurements proved its high durability, maintaining its initial current density up to 98.3% at 0.3 VRHE and 93.7% at 0.75 VRHE, whereas other catalysts remained below 90% at all potentials. These outcomes are considered that the doped nitrogen atoms bond with the NPs stably, and their electron-rich states facilitate the interaction with the reactants on the surface. In conclusion, the catalyst can be applied to the fuel cell system, overcoming the high cost, activity, and durability issues.

| S-EPMC8538997 | biostudies-literature

Nitrogen-doped Graphene-Supported Transition-metals Carbide Electrocatalysts for Oxygen Reduction Reaction.

Project description:A novel and facile two-step strategy has been designed to prepare high performance bi-transition-metals (Fe- and Mo-) carbide supported on nitrogen-doped graphene (FeMo-NG) as electrocatalysts for oxygen reduction reactions (ORR). The as-synthesized FeMo carbide -NG catalysts exhibit excellent electrocatalytic activities for ORR in alkaline solution, with high onset potential (-0.09 V vs. saturated KCl Ag/AgCl), nearly four electron transfer number (nearly 4) and high kinetic-limiting current density (up to 3.5 mA cm(-2) at -0.8 V vs. Ag/AgCl). Furthermore, FeMo carbide -NG composites show good cycle stability and much better toxicity tolerance durability than the commercial Pt/C catalyst, paving their application in high-performance fuel cell and lithium-air batteries.

| S-EPMC4441168 | biostudies-literature

Synthesis of 2D Nitrogen-Doped Mesoporous Carbon Catalyst for Oxygen Reduction Reaction.

Project description:2D nitrogen-doped mesoporous carbon (NMC) is synthesized by using a mesoporous silica film as hard template, which is then investigated as a non-precious metal catalyst for the oxygen reduction reaction (ORR). The effect of the synthesis conditions on the silica template and carbon is extensively investigated. In this work, we employ dual templates-viz. graphene oxide and triblock copolymer F127-to control the textural features of a 2D silica film. The silica is then used as a template to direct the synthesis of a 2D nitrogen-doped mesoporous carbon. The resultant nitrogen-doped mesoporous carbon is characterized by transmission electron microscopy (TEM), nitrogen ad/desorption isotherms, X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), and rotating disk electrode measurements (RDE). The electrochemical test reveals that the obtained 2D-film carbon catalyst yields a highly electrochemically active surface area and superior electrocatalytic activity for the ORR compared to the 3D-particle. The superior activity can be firstly attributed to the difference in the specific surface area of the two catalysts. More importantly, the 2D-film morphology makes more active sites accessible to the reactive species, resulting in a much higher utilization efficiency and consequently better activity. Finally, it is noted that all the carbon catalysts exhibit a higher ORR activity than a commercial Pt catalyst, and are promising for use in fuel cells.

| S-EPMC5459128 | biostudies-literature

Novel Porous Nitrogen Doped Graphene/Carbon Black Composites as Efficient Oxygen Reduction Reaction Electrocatalyst for Power Generation in Microbial Fuel Cell.

Project description:To improve the power generation of a microbial fuel cell (MFC), a porous nitrogen-doped graphene/carbon black (NG/CB) composite as efficient oxygen reduction reaction (ORR) electrocatalyst was successfully synthesized by pyrolyzing graphene oxide (GO) encapsulated CB with cetyltrimethyl ammonium bromide as a bridge. This concept-to-proof synthesis can be considered as a template-like method. Based on this method, one composite named as NG/CB-10 was acquired using the optimized GO-to-CB mass ratio of 10:1. Electrochemical tests demonstrate that NG/CB-10 can catalyze ORR in neutral-pH medium through a four-electron pathway with positively shifted the onset potential, the enhanced current density and reduced charge transfer resistance. CB addition also prolongs the stability of NG/CB-10. The enhancement in electrochemical performance of NG/CB-10 was attributed to the enlarged surface area, abundant mesopores and high content of pyridinic nitrogen. The maximum power density of MFC equipping NG/CB-10 as cathode electrocatalyst reached 936 mW·m-2, which was 26% higher than that of NG and equal to that of platinum/carbon. The cost of NG/CB-10 was reduced by 25% compared with that of NG. This work provides a novel method to synthesize promising ORR electrocatalyst for MFC in the future.

| S-EPMC6631044 | biostudies-literature

Nitrogen-Doped Carbon Nanosheets Decorated With Mn2O3 Nanoparticles for Excellent Oxygen Reduction Reaction.

Project description:The purpose of this study is to develop an active, low cost, non-precious, stable, and high-performance catalyst for oxygen reduction reaction (ORR). In this regard, Mn2O3-decorated nitrogen-doped carbon nanosheets (Mn2O3/NC) are fabricated by a two-step strategy involving a hydrothermal method and a solid-state method. In the resultant structures, very fine Mn2O3 nanoparticles with an average size of about 5 nm are strongly attached to nitrogen-doped carbon nanosheets. The role of the Mn2O3 nanoparticles is to provide active sites for ORR, while the presence of the nitrogen-doped carbon not only enhances the conductivity of the overall structure but is also helpful for overall stability. The Mn2O3/NC shows good onset potential (0.80 V@-1 mA/cm2), methanol crossover effect, and stability (90%).

| S-EPMC6856643 | biostudies-literature

Nitrogen-Doped Porous Carbon Derived from Biomass Used as Trifunctional Electrocatalyst toward Oxygen Reduction, Oxygen Evolution and Hydrogen Evolution Reactions.

Project description:Tremendous developments in energy storage and conversion technologies urges researchers to develop inexpensive, greatly efficient, durable and metal-free electrocatalysts for tri-functional electrochemical reactions, namely oxygen reduction reactions (ORRs), oxygen evolution reactions (OERs) and hydrogen evolution reactions (HERs). In these regards, this present study focuses upon the synthesis of porous carbon (PC) or N-doped porous carbon (N-PC) acquired from golden shower pods biomass (GSB) via solvent-free synthesis. Raman spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) studies confirmed the doping of nitrogen in N-PC. In addition, morphological analysis via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) provide evidence of the sheet-like porous structure of N-PC. ORR results from N-PC show the four-electron pathway (average n = 3.6) for ORRs with a Tafel slope of 86 mV dec-1 and a half-wave potential of 0.76 V. For OERs and HERs, N-PC@Ni shows better overpotential values of 314 and 179 mV at 10 mA cm-2, and its corresponding Tafel slopes are 132 and 98 mV dec-1, respectively. The chronopotentiometry curve of N-PC@Ni reveals better stability toward OER and HER at 50 mA cm-2 for 8 h. These consequences provide new pathways to fabricate efficient electrocatalysts of metal-free heteroatom-doped porous carbon from bio-waste/biomass for energy application in water splitting and metal air batteries.

| S-EPMC7022927 | biostudies-literature

Theoretical Study on a Nitrogen-Doped Graphene Nanoribbon with Edge Defects as the Electrocatalyst for Oxygen Reduction Reaction.

Project description:Both theory and experiment show that sp2 carbon nanomaterials doped with N have great potential as high-efficiency catalysts for oxygen reduction reactions (ORR). At present, there are theoretical studies that believe that C-sites with positive charge or high-spin density values have higher adsorption capacity, but there are always some counter examples, such as the N-doped graphene nanoribbons with edge defects (ND-GNR) of this paper. In this study, the ORR mechanism of ND-GNR was studied by density functional theory (DFT) calculation, and then the carbon ring resonance energy was analyzed from the perspective of chemical graph theory to elucidate the cause and distribution of active sites in ND-GNR. Finally, it was found that the overpotential of the model can be adjusted by changing the width of the model or dopant atoms while still ensuring proper adsorption energy (between 0.5 and 2.0 eV). The minimum overpotential for these models is approximately 0.36 V. These findings could serve as guidelines for the construction of efficient ORR carbon nanomaterial catalysts.

| S-EPMC7081414 | biostudies-literature

Biomass Juncus Derived Nitrogen-Doped Porous Carbon Materials for Supercapacitor and Oxygen Reduction Reaction.

Project description:Juncus is a perennial herb aquatic plant found worldwide, with high reproductive ability in warm regions. It has three-dimensional hierarchical porous triangular networks structures composited of tubular fibers. Here, juncus derived nitrogen-doped porous carbon (NDPC) was prepared by mixing juncus and ZnCl2 through one-step pyrolysis and activation which is a low-cost, simple, and environmentally friendly method. The NDPC had hierarchical porous structures and a high specific surface area and was applied for supercapacitor and oxygen reduction reaction (ORR). The resulted NDPC-3-800 was prepared by mixing juncus with ZnCl2 at a mass ratio of 1:3 and then carbonized at 800°C, it was used as electrode material of a supercapacitor. The supercapacitor exhibited excellent specific capacitance of 290.5 F g-1 and 175.0 F g-1 in alkaline electrolyte at the current densities of 0.5 A g-1 and 50 A g-1, respectively. The supercapacitor showed good cycle stability, and the capacitance was maintained at 94.5% after 10,000 cycles. The NDPC-5-800 was prepared by mixing juncus with ZnCl2 at a mass ratio of 1:5 and then carbonized at 800°C. It exhibited outstanding ORR catalytic activity and stability attributing to their high specific surface area and abundant actives sites. The juncus can derive various materials for application in different fields.

| S-EPMC7174754 | biostudies-literature

Alloyed Pt<sub>3</sub>M (M = Co, Ni) nanoparticles supported on S- and N-doped carbon nanotubes for the oxygen reduction reaction.

Project description:Sulfur- (S-CNT) and nitrogen-doped (N-CNT) carbon nanotubes have been produced by catalytic chemical vapor deposition (c-CVD) and were subject to an annealing treatment. These CNTs were used as supports for small (≈2 nm) Pt3M (M = Co or Ni) alloyed nanoparticles that have a very homogeneous size distribution (in spite of the high metal loading of ≈40 wt % Pt), using an ionic liquid as a stabilizer. The electrochemical surface area, the activity for the oxygen reduction reaction and the amount of H2O2 generated during the oxygen reduction reaction (ORR) have been evaluated in a rotating ring disk electrode experiment. The Pt3M/N-CNT catalysts revealed excellent electrochemical properties compared to a commercial Pt3Co/Vulcan XC-72 catalyst. The nature of the carbon support plays a key role in determining the properties of the metal nanoparticles, on the preparation of the catalytic layer, and on the electrocatalytic performance in the ORR. On N-CNT supports, the specific activity followed the expected order Pt3Co > Pt3Ni, whereas on the annealed N-CNT support, the order was reversed.

| S-EPMC6604734 | biostudies-literature

Transition Metal (Fe, Co, Ni) Nanoparticles on Selective Amino-N-Doped Carbon as High-Performance Oxygen Reduction Reaction Electrocatalyst.

Project description:Metal-air batteries are attracting increasing attention as a superior renewable energy conversion device due to their high performance and strong potential. However, the high cost and low stability of the current Pt catalyst is the main obstacle preventing wide industrial application. In this work, we applied a plasma process to fabricate aniline and a transition metals electrode (Fe, Co, Ni) as the carbon-nitrogen and the metal nanoparticle (NP) precursors, respectively, for selective metal/amino-N-doped carbon catalysts. All three as-synthesized catalysts exhibited dominant amino-N as the major C-N bonding state. In electrochemical testing, Co/amino-N-doped carbon showed positive E1/2 potential (0.83 V vs. Reversible Hydrogen Electrode (RHE)). In addition, the calculated electron transfer number (n) of Co/amino-N-doped carbon at 0.5 V vs. RHE was 3.81, which was only slightly less than that of commercial Pt/C (3.97). This superior performance of transition metal/amino-N-doped carbon promotes it as an economical oxygen reduction reaction (ORR) electrocatalyst to replace expensive Pt/C in metal-air batteries.

| S-EPMC6566341 | biostudies-literature