Browse
Submit Data
Databases
API
Help

Dataset Information

31 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Highly ordered macroporous dual-element-doped carbon from metal-organic frameworks for catalyzing oxygen reduction.

ABSTRACT: Multiple heteroatom-doped carbons with 3D ordered macro/meso-microporous structures have not been realized by simple carbonization of metal-organic frameworks (MOFs). Herein, ordered macroporous phosphorus- and nitrogen-doped carbon (M-PNC) is prepared successfully by carbonization of double-solvent-induced MOF/polystyrene sphere (PS) precursors accompanied with spontaneous removal of the PS template, followed by post-doping. M-PNC shows a high specific surface area of 837 m² g^-1, nitrogen doping of 3.17 at%, and phosphorus doping of 1.12 at%. Thanks to the hierarchical structure, high specific surface area, and multiple heteroatom-doping, M-PNC exhibits unusual catalytic activity as an electrocatalyst for the oxygen reduction reaction. Computational calculation reveals that the P[double bond, length as m-dash]O group helps stabilize the adsorption of intermediates, and the position of P[double bond, length as m-dash]O relative to graphitic N significantly improves the activity of the adjacent carbons for electrocatalysis.

SUBMITTER: Xia W

PROVIDER: S-EPMC8162149 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Hierarchical Structure with Highly Ordered Macroporous-Mesoporous Metal-Organic Frameworks as Dual Function for CO<sub>2</sub> Fixation.

Project description:As a major greenhouse gas, the continuous increase of carbon dioxide (CO2) in the atmosphere has caused serious environmental problems, although CO2 is also an abundant, inexpensive, and nontoxic carbon source. Here, we use metal-organic framework (MOF) with highly ordered hierarchical structure as adsorbent and catalyst for chemical fixation of CO2 at atmospheric pressure, and the CO2 can be converted to the formate in excellent yields. Meanwhile, we have successfully integrated highly ordered macroporous and mesoporous structures into MOFs, and the macro-, meso-, and microporous structures have all been presented in one framework. Based on the unique hierarchical pores, high surface area (592 m2/g), and high CO2 adsorption capacity (49.51 cm3/g), the ordered macroporous-mesoporous MOFs possess high activity for chemical fixation of CO2 (yield of 77%). These results provide a promising route of chemical CO2 fixation through MOF materials.

| S-EPMC6538925 | biostudies-literature

A Unique Synthesis of Macroporous N-Doped Carbon Composite Catalyst for Oxygen Reduction Reaction.

Project description:Macroporous carbon materials (MCMs) are used extensively for many electrocatalytic applications, particularly as catalysts for oxygen reduction reactions (ORRs)-for example, in fuel cells. However, complex processes are currently required for synthesis of MCMs. We present a rapid and facile synthetic approach to produce tailored MCMs efficiently via pyrolysis of sulfonated aniline oligomers (SAOs). Thermal decomposition of SAO releases SO2 gas which acts as a blowing agent to form the macroporous structures. This process was used to synthesise three specifically tailored nitrogen (N)-doped MCM catalysts: N-SAO, N-SAO (phenol formaldehyde) (PF) and N-SAO-reduced graphene oxide (rGO). Analysis using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction (XRD) analysis confirmed the formation of macropores (100-350 µm). Investigation of ORR efficacy showed that N-SAOPF performed with the highest onset potential of 0.98 V (vs. RHE) and N-SAOrGO showed the highest limiting current density of 7.89 mAcm-2. The macroporous structure and ORR efficacy of the MCM catalysts synthesised using this novel process suggest that this method can be used to streamline MCM production while enabling the formation of composite materials that can be tailored for greater efficiency in many applications.

| S-EPMC7824199 | biostudies-literature

Synthesis of ordered carbonaceous frameworks from organic crystals.

Project description:Despite recent advances in the carbonization of organic crystalline solids like metal-organic frameworks or supramolecular frameworks, it has been challenging to convert crystalline organic solids into ordered carbonaceous frameworks. Herein, we report a route to attaining such ordered frameworks via the carbonization of an organic crystal of a Ni-containing cyclic porphyrin dimer (Ni2-CPDPy). This dimer comprises two Ni-porphyrins linked by two butadiyne (diacetylene) moieties through phenyl groups. The Ni2-CPDPy crystal is thermally converted into a crystalline covalent-organic framework at 581 K and is further converted into ordered carbonaceous frameworks equipped with electrical conductivity by subsequent carbonization at 873-1073 K. In addition, the porphyrin's Ni-N4 unit is also well retained and embedded in the final framework. The resulting ordered carbonaceous frameworks exhibit an intermediate structure, between organic-based frameworks and carbon materials, with advantageous electrocatalysis. This principle enables the chemical molecular-level structural design of three-dimensional carbonaceous frameworks.Carbon-based materials are promising alternatives to noble metal catalysts, but their structures are typically disordered and difficult to control. Here, the authors obtain ordered carbonaceous frameworks with advantageous electrocatalytic properties via the carbonization of nickel-containing porphyrin dimer networks.

| S-EPMC5524644 | biostudies-literature

Encoding ordered structural complexity to covalent organic frameworks.

Project description:Installing different chemical entities onto crystalline frameworks with well-defined spatial distributions represents a viable approach to achieve ordered and complex synthetic materials. Herein, a covalent organic framework (COF-305) is constructed from tetrakis(4-aminophenyl)methane and 2,3-dimethoxyterephthalaldehyde, which has the largest unit cell and asymmetric unit among known COFs. The ordered complexity of COF-305 is embodied by nine different stereoisomers of its constituents showing specific sequences on topologically equivalent sites, which can be attributed to its building blocks deviating from their intrinsically preferred simple packing geometries in their molecular crystals to adapt to the framework formation. The insight provided by COF-305 supplements the principle of covalent reticular design from the perspective of non-covalent interactions and opens opportunities for pursuing complex chemical sequences in molecular frameworks.

| S-EPMC10948875 | biostudies-literature

Advanced Bifunctional Oxygen Reduction and Evolution Electrocatalyst Derived from Surface-Mounted Metal-Organic Frameworks.

Project description:Metal-organic frameworks (MOFs) and their derivatives are considered as promising catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), which are important for many energy provision technologies, such as electrolyzers, fuel cells and some types of advanced batteries. In this work, a "strain modulation" approach has been applied through the use of surface-mounted NiFe-MOFs in order to design an advanced bifunctional ORR/OER electrocatalyst. The material exhibits an excellent OER activity in alkaline media, reaching an industrially relevant current density of 200?mA?cm-2 at an overpotential of only ?210?mV. It demonstrates operational long-term stability even at a high current density of 500?mA?cm-2 and exhibits the so far narrowest "overpotential window" ?EORR-OER of 0.69?V in 0.1?m KOH with a mass loading being two orders of magnitude lower than that of benchmark electrocatalysts.

| S-EPMC7154533 | biostudies-literature

Creation of Triple Hierarchical Micro-Meso-Macroporous N-doped Carbon Shells with Hollow Cores Toward the Electrocatalytic Oxygen Reduction Reaction.

Project description:A series of triple hierarchical micro-meso-macroporous N-doped carbon shells with hollow cores have been successfully prepared via etching N-doped hollow carbon spheres with CO2 at high temperatures. The surface areas, total pore volumes and micropore percentages of the CO2-activated samples evidently increase with increasing activation temperature from 800 to 950 °C, while the N contents show a contrary trend from 7.6 to 3.8 at%. The pyridinic and graphitic nitrogen groups are dominant among various N-containing groups in the samples. The 950 °C-activated sample (CANHCS-950) has the largest surface area (2072 m2 g-1), pore volume (1.96 cm3 g-1), hierarchical micro-mesopore distributions (1.2, 2.6 and 6.2 nm), hollow macropore cores (~91 nm) and highest relative content of pyridinic and graphitic N groups. This triple micro-meso-macropore system could synergistically enhance the activity because macropores could store up the reactant, mesopores could reduce the transport resistance of the reactants to the active sites, and micropores could be in favor of the accumulation of ions. Therefore, the CANHCS-950 with optimized structure shows the optimal and comparable oxygen reduction reaction (ORR) activity but superior methanol tolerance and long-term durability to commercial Pt/C with a 4e--dominant transfer pathway in alkaline media. These excellent properties in combination with good stability and recyclability make CANHCSs among the most promising metal-free ORR electrocatalysts reported so far in practical applications.

| S-EPMC6199056 | biostudies-literature

Metal-Organic-Framework-Derived Dual Metal- and Nitrogen-Doped Carbon as Efficient and Robust Oxygen Reduction Reaction Catalysts for Microbial Fuel Cells.

Project description:A new class of dual metal and N doped carbon catalysts with well-defined porous structure derived from metal-organic frameworks (MOFs) has been developed as a high-performance electrocatalyst for oxygen reduction reaction (ORR). Furthermore, the microbial fuel cell (MFC) device based on the as-prepared Ni/Co and N codoped carbon as air cathode catalyst achieves a maximum power density of 4335.6 mW m-2 and excellent durability.

| S-EPMC5063114 | biostudies-literature

Charging modulation of the pyridine nitrogen of covalent organic frameworks for promoting oxygen reduction reaction.

Project description:Covalent organic frameworks (COFs) are ideal templates for constructing metal-free catalysts for the oxygen reduction reaction due to their highly tuneable skeletons and controllable porous channels. However, the development of highly active sites within COFs remains challenging due to their limited electron-transfer capabilities and weak binding affinities for reaction intermediates. Herein, we constructed highly active catalytic centres by modulating the electronic states of the pyridine nitrogen atoms incorporated into the frameworks of COFs. By incorporating different pyridine units (such as pyridine, ionic pyridine, and ionic imidazole units), we tuned various properties including dipole moments, reductive ability, hydrophilicity, and binding affinities towards reaction intermediates. Notably, the ionic imidazole COF (im-PY-BPY-COF) exhibited greater activity than the neutral COF (PY-BPY-COF) and ionic pyridine COF (ion-PY-BPY-COF). Specifically, im-PY-BPY-COF demonstrated a half-wave potential of 0.80 V in 0.1 M KOH, outperforming other metal-free COFs. Theoretical calculations and in situ synchrotron radiation Fourier transform infrared spectroscopy confirmed that the carbon atoms in the ionic imidazole rings improved the activity by facilitating binding of the intermediate OOH* and promoting the desorption of OH*. This study provides new insights into the design of highly active metal-like COF catalysts.

| S-EPMC10904383 | biostudies-literature

Ice crystals growth driving assembly of porous nitrogen-doped graphene for catalyzing oxygen reduction probed by in situ fluorescence electrochemistry.

Project description:In recent years, doped carbonaceous materials as alternative catalysts for oxygen reduction reaction (ORR) have received considerable attention due to the low cost and high CO tolerance capability. Different theoretical studies have suggested that oxygen is reduced in a rapid sequence intermediated by diverse oxygen-containing reactive intermediates (ORI). However, due to the short lifetimes of the possible ORI, direct experimental evidence is very difficult to be obtained. Here, we report the synthesis of an ultralight and porous nitrogen-doped graphene (NG) by annealing graphite oxide (GO)-melamine scaffold shaped in ice template. The resultant NG exhibits excellent electrocatalytic activity toward 4e-reduction of oxygen with the onset potential as low as -0.05?V vs. Ag/AgCl in alkaline media. Using this material as model study, sensitive in situ fluorescence spectroelectrochemistry is applied to demonstrate the presence the reactive ORI. The global ORR pathway is unraveled as stepwise electron transfer involving hydroxyl radical as the important intermediate via both inner- and outer-sphere process. This result would likely provide a new insight into the further understanding of ORR mechanism on those intrinsic carbonaceous materials.

| S-EPMC4205891 | biostudies-other

Cobalt Nanoparticles Embedded into N-Doped Carbon from Metal Organic Frameworks as Highly Active Electrocatalyst for Oxygen Evolution Reaction.

Project description:Cystosepiment-like cobalt nanoparticles@N-doped carbon composite named Co-NPs@NC with highly efficient electrocatalytic performance for oxygen evolution reaction was prepared from carbonization of N-doped Co-MOFs. The optimized Co-NPs@NC-600 shows overpotentials of 315 mV to afford a current density of 10 mA·cm-2. Meanwhile, the electrocatalys presents excellent long-term durability. The outstanding electrocatalytic performance can be attributed to the unique cystosepiment-like architecture with high specific surface area (214 m2/g), high conductivity of N-doped carbon and well-distributed active sites.

| S-EPMC6572389 | 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