Carbon Nanorods Research Articles

Poly(ionic liquids) derived N, S co-doped carbon nanorod from in situ and template-free method as an efficient metal-free bifunctional electrocatalysts for direct methanol fuel cells

Developing highly efficient strategy for fabrication of bifunctional electrocatalysts for oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) is a challenging topic. In this work, we reported the in situ synthesis of N, S co-doped carbon nanorod material (N/S-C) by the facile template-free, one-step pyrolysis approach using N and S co-containing poly(ionic liquid) (PIL) of p[BZ][HSO 4 ] 2 as precursor derived from the simple chemically oxidative polymerization of ionic liquid benzidine sulfate ([BZ][HSO 4 ] 2 ) in the presence of ammonium persulfate as oxidant. The N/S-C catalysts have nanorod morphology with hierarchical porous architectures of abundant micropores and well-defined mesopores featuring high specific surface areas. The ORR performance of N/S-C-800 is extremely satisfactory in alkaline media with the onset and half-potentials of 0.985 V and 0.857 V (vs. RHE), respectively, which are comparable to that of commercial Pt/C (0.990 V and 0.852 V vs. RHE). It also delivers the favorable long-term stability and methanol tolerance, significantly outperforming commercial Pt/C. Moreover, the N/S-C-800 was served as a support for Pt nanoparticles, showing the higher methanol electrooxidation activity (806.74 mA mg Pt -1 ) compared with commercial Pt/C (356.32 mA mg Pt -1 ). These results show an effective route to design the attractive metal-free carbon-based electrocatalysts for direct methanol fuel cells. • The N/S co-doped carbon nanorod material was synthesized in situ via facile one-step pyrolysis approach using the poly(ionic liquids) (PILs) as precursor. • The N/S-C-800 catalyst exhibited the superior ORR activity and stability in alkaline media. • The Pt nanoparticles supported on the N/S-C-800 catalyst showed superior MOR activity.

Novel peapod-like Ni2P@N-doped carbon nanorods array on carbon fiber for efficient electrocatalytic urea oxidation and hydrogen evolution reaction

Designing and optimizing structure is an effective method to enhance electrocatalytic performance of transition metal-based catalysts. In this work, an innovative nanostructured electrode, consisted of peapod-like Ni2P@N-doped carbon nanorods array coating on carbon fiber (CF@p-Ni2P@NC), is devised and synthesized. The N-doped carbon layer is crucial for maintaining the peapod-like nanostructure, which allows for multi-channel electrolyte transport and gas product release. And the carbon layer coating Ni2P nanoparticles also enhance electrical conductivity and stability, thus ensuring fast electron transport from/to active sites and the long-term stability of catalyst during urea oxidation reaction (UOR)/hydrogen evolution reaction (HER). Benefit from the reasonable structure, CF@p-Ni2P@NC present perfect performance with getting 100 mA cm−2 at potential/overpotential of 1.417/0.194 V for UOR/HER in 1.0 M KOH containing 0.5 M urea. In addition, the overall urea-electrolysis system using CF@p-Ni2P@NC bifunctional electrode only requires 1.590 V to obtain 100 mA cm−2.

Rational design of a hollow porous structure for enhancing diffusion kinetics of K ions in edge-nitrogen doped carbon nanorods

Rational design of a hollow porous structure for enhancing diffusion kinetics of K ions in edge-nitrogen doped carbon nanorods

ZIF‐Mediated Anchoring of Co species on N‐doped Carbon Nanorods as an Efficient Cathode Catalyst for Zn‐Air Batteries

Developing efficient oxygen reduction reaction (ORR) catalyst is essential for the practical application of Zn‐air batteries (ZABs). In this contribution, we develop a novel zeolitic imidazolate framework (ZIF)‐mediated strategy to anchor Co species on N‐doped carbon nanorods for efficient ORR. Featuring ultrahigh N‐doping (10.29 at.%), monodisperse Co nanocrystal decoration, and well‐dispersed Co‐Nx functionalization, the obtained Co‐decorated N‐doped carbon nanorods (Co@NCNR) exhibit a decent ORR performance comparable to commercial Pt/C in alkaline media. Aqueous ZABs have been assembled using Co@NCNR as the cathode catalyst. The assembled ZABs manifest high initial open‐circuit voltage as well as high energy density. In addition, the Co@NCNR also demonstrates ideal ORR performance in quasi‐solid‐state ZABs.

Mesopore-Rich Fe-N-C Catalyst with FeN4 -O-NC Single-Atom Sites Delivers Remarkable Oxygen Reduction Reaction Performance in Alkaline Media.

Fe-N-C catalysts offer excellent performance for the oxygen reduction reaction (ORR) in alkaline media. With a view toward boosting the intrinsic ORR activity of Fe single-atom sites in Fe-N-C catalysts, fine-tuning the local coordination of the Fe sites to optimize the binding energies of ORR intermediates is imperative. Herein, a porous FeN4 -O-NCR electrocatalyst rich in catalytically accessible FeN4 -O sites (wherein the Fe single atoms are coordinated to four in-plane nitrogen atoms and one subsurface axial oxygen atom) supported on N-doped carbon nanorods (NCR) is reported. Fe K-edge X-ray absorption spectroscopy (XAS) verifies the presence of FeN4 -O active sites in FeN4 -O-NCR, while density functional theory calculations reveal that the FeN4 -O coordination offers a lower energy and more selective 4-electron/4-proton ORR pathway compared to traditional FeN4 sites. Electrochemical tests validate the outstanding intrinsic activity of FeN4 -O-NCR for alkaline ORR, outperforming Pt/C and almost all other M-N-C catalysts reported to date. A primary zinc-air battery constructed using FeN4 -O-NCR delivers a peak power density of 214.2mWcm-2 at a current density of 334.1mAcm-2 , highlighting the benefits of optimizing the local coordination of iron single atoms.

Carbon nanorods assembled coral-like hierarchical meso-macroporous carbon as sustainable materials for efficient biosensing and biofuel cell

Sustainable conversion of renewable biomass into high-performance electrode materials has attracted extensive scientific and technological attention. However, to our knowledge, the potential of biomass derived carbon in biosensors and biofuel cells (BFCs) developments remains to be explored. Herein, the carbon nanorods assembled coral-like hierarchical meso-macroporous carbon (CN-CHMC) was synthesized as a sustainable electrode material to construct biosensor and lactate/air BFC. The CN-CHMC from cucumber (Cucumis sativus) possesses porous structure and plentiful defects, which not only facilitate the effective immobilization of enzymes but also accelerate electron transfer on the bioelectrode surfaces. As an electrochemical lactate biosensor, the CN-CHMC-based biosensor exhibits a wider linear range with lower detection limit (3.6 μM) and higher sensitivities (57.18 and 30.99 μA mM−1 cm−2) compared to carbon nanotube (CNT)-based biosensor. The feasibility of CN-CHMC-based biosensor in practical analysis is demonstrated by detecting lactate contents in real samples. By coupling with bilirubin oxidase-based biocathode, the lactate/air BFC equipped with CN-CHMC reveals a higher output power (112.7 μW cm−2) than that of CNT-based BFC. More interestingly, the lactate/air BFC demonstrates the ability to harvest energy from multi-component samples. The application of CN-CHMC may provide a new avenue to synthesize electrode materials with economical cost and excellent electrochemical activity.

N-Doped Carbon Nanorods from Biomass as a Potential Antidiabetic Nanomedicine.

Insufficient glucose control remains a critical challenge for type 2 diabetes mellitus (T2DM) patients with currently used therapeutic drugs, which can also have detrimental side effects. The facile synthesis of nitrogen-doped carbon nanorods (N-CNRs) as therapeutic agents in a T2DM transgenic db/db mouse model is reported herein. N-CNRs are synthesized from silkworm powder without the assistance of any template and possess a hollow graphitic nature, rough surface, and good aqueous solubility, which make them ideal candidates for fabricating nanomedicines. N-CNRs are employed to reduce fasting blood glucose and ameliorate serum biomarker levels linked to oxidative stress and inflammation. Interestingly, through the downregulation of enhanced expression of glutathione peroxidase, superoxide dismutase, and catalase as well as inflammatory responses, N-CNRs reverse pancreatic dysfunction and normalize the secretory functions of pancreatic cells. Moreover, hepatic steatosis is attenuated by downregulating lipogenesis and increasing fatty acid oxidation. This finding may help in designing novel therapeutics for T2DM treatment.

Self-supported metal (Fe, Co, Ni)-embedded nitrogen-doping carbon nanorod framework as trifunctional electrode for flexible Zn-air batteries and switchable water electrolysis

To meet the practical demand of wearable/portable electronics, developing high-efficiency and durable multifunctional catalyst and in-situ assembling catalysts into electrodes with flexible features are urgently needed but challenging. Herein, we report a simple route to fabricate bendable multifunctional electrodes by in-situ carbonization of metal ion absorbed polyaniline precursor. Alloy nanoparticles encapsulated in graphite layer are uniformly distributed in the N-doping carbon nanorod skeleton. Profiting from the favorable free-standing structure and the cooperative effect of metallic nanoparticles, graphitic layer and N doped-carbon architecture, the trifunctional electrodes exhibit prominent activities and stability toward HER, OER and ORR. Notably, due to the protection of carbon layer, the electrocatalysts show the reversible catalytic HER/OER properties. The overall water splitting device can continuously work for 12 h under frequent exchanges of cathode and anode. Importantly, the bendable metal air batteries fabricated by self-supported electrode not only displays the outstanding battery performance, achieving a decent peak power density (125 mW cm−2) and exhibiting favorable charge-discharge durability of 22 h, but also holds superb flexible stability. Specially, a lightweight self-driven water splitting unit is demonstrated with stable hydrogen production.

Threading the MOF-derived mesoporous carbon host with CNT network: An effective modification layer for high-areal-capacity Li metal anodes

• The lightweight Al-MOF derived interfacial layer (0.39 mg cm −2 ) is constructed. • Atomically dispersed Al species engineer the lithiophilicity within the layer. • The interweaved CNTs reinforce the structural integrity of the interfacial layer. • As-constructed full cell achieves Energy/power dense metallic battery system. The ramified lithium dendrite growth and severe volume expansion upon the metallic plating process impede the practical deployment of the lithium metal anode in the energy-dense battery system. In this article, a thin modification layer of the Al-based metal–organic framework (MOF) is carbonized into the mesoporous carbon nanorods (PCRs) with atomically dispersed lithiophilic sites; meanwhile these storage units are structurally reinforced by the in-situ grown carbon nanotubes. The interfacial engineered substrate (Al-PCRs/CNTs-Cu) exhibits an enhanced Li affinity with mitigated nucleation barrier, and thus realizes the long-lifespan up to 1000 h at high-capacity-loading of 8 mAh cm −2 . When integrating the modified substrate with LiN 0.8 Co 0.1 Mn 0.1 O 2 (NCM-811) (∼10.5 mg cm −2 ) the cathode in a prelithiated full cell model (2*Li excess), the prototype exhibits a high energy density of 414.38 Wh kg −1 at the highest power density of 1243.14 W kg −1 . This dual-functionalized, carbonaceous interfacial layer provides a facile and effective approach to construct the energy/power-dense metallic batteries.

In Situ Carbonization Combined with a Low-Temperature Graphitization Technique for Preparation of CdS@graphitic Carbon Nanorods and Their Robust Photocatalytic Performance under Visible Light

In Situ Carbonization Combined with a Low-Temperature Graphitization Technique for Preparation of CdS@graphitic Carbon Nanorods and Their Robust Photocatalytic Performance under Visible Light

Synthesis of one-dimensional vanadium-doped CoS/Co9S8 heterojunctions as bifunctional electrocatalysts for zinc-air battery

Cobalt-based electrocatalysts have been considered promising materials for the oxygen evolution reaction (OER). Herein, we now report the synthesis of vanadium-doped CoS/Co9S8 heterostructures embedded on carbon nanorods (V-CoS/Co9S8@CNR), which was realized through one-step sulfurization of Zeolitic Imidazolate Framework-67 (ZIF-67) grown on V2O5 nanorods (V2O5@ZIF-67). The results of experiment and theoretical calculation verified that because of the vanadium dopant and the coupled nanointerface that can expedite the synergistic effect of Co9S8 and CoS, the obtained V-CoS/Co9S8@CNR showed an excellent OER catalytic performance (269 mV@10 mA/cm2) and comparable ORR catalytic performance. The assembled rechargeable Zn-air batteries displayed a superior performance as well as high charging–discharging cycling stability (>200 h) with a slight increase in the voltage gap.

Spiral effect of helical carbon nanorods boosting electrocatalysis of oxygen reduction reaction

Helical metal-organic frameworks (MOFs) were used as templates or precursors to fabricate helical carbon nanorods (HCNRs) for the first time. Helical carbon contains many topological defects such as pentagonal or heptagonal carbons, which have the potential to facilitate oxygen reduction reactions (ORR). HCNRs show more positive onset/half-wave reduction potentials and higher limited current density than straight carbon nanorods (SCNRs). They also exhibit four-electron oxygen reduction in tests of ORR, while the alternative SCNRs prefer a two-electron reduction mechanism. Experimental and theoretical studies reveal that these enhanced ORR activities can be attributed to pentagon/heptagon defects in HCNRs. This work provides an effective strategy to synthesize helical, defect-rich carbon materials and opens up a new perspective for utilization of a spiral effect for the development of more effective electrocatalysts.

A fully-conjugated covalent organic framework-derived carbon supporting ultra-close single atom sites for ORR

Covalent organic frameworks linked by CC bonds have gained great attention for various application, and their fully conjugated skeletons were potentially conversed into two-dimensional (2D) carbons. Herein, we described a novel strategy to fabricate 2D carbon nanorods from a sp2 carbon linked COF, which had a high surface area of 804.8 m2 g−1. The one-dimensional channels confined the Fe ions during pyrolysis, which facilitated to form ultra-close atomic sites. The resulting catalyst displayed high catalytic activity towards oxygen reduction reaction, with a half-wave potential of 0.82 V and a mass activity of 4087.9 mA mg−1 at 0.7 V versus RHE, which were high than those of Pt/C (0.81 V and 126.3 mA mg−1). The theoretical calculation revealed the close FeN4 sites achieved a lower *OH adsorption energy than isolated FeN4 sites. This work provides a new insight into developing single atom catalysts from COFs.

Extraordinary Compatibility to Mass Loading and Rate Capability of Hierarchically Porous Carbon Nanorods Electrode Derived from the Waste Tire Pyrolysis Oil

The conversion of waste tire pyrolysis oil (WTPO) into S‐doped porous carbon nanorods (labeled as WPCNs) with hierarchical pore structure is realized by a simple template‐directed approach. The specific surface area of as‐obtained porous carbon nanorods can reach up to 1448 m2 g−1 without the addition of any activating agent. As the capacitive electrode, WPCNs possess the extraordinary compatibility to capacitance, different electrolyte systems as well as long‐term cycle life even at a commercial‐level areal mass loading (10 mg cm−2). Besides, only an extremely small capacitance fluctuation is observed under the extreme circumstance (−40 to 80 °C), reflecting the excellent high‐ and low‐temperature performance. The relationship between the pore structure and capacitive behavior is analyzed by comparing WPCNs with mesopores‐dominated asphalt‐derived porous carbon nanorods (APCNs) and micropores‐dominated activated carbon. The molecular dynamics simulation further reveals the ion diffusion and transfer ability of the as‐prepared carbon materials under different pore size distribution. The total ion flow (NT) of WPCNs calculated by the simulation is obviously larger than APCNs and the NT ratio between them is similar with the experimental average capacitance ratio. Furthermore, this work also provides a valuable strategy to prepare the electrode material with high capacitive energy storage ability through the high value‐added utilization of WTPO.

Boosting electromagnetic wave absorption properties via the sulfidation strategy of Fe/Fe3C/N-doped carbon nanorods hybrids

Exploring novel electromagnetic wave (EMW) absorption materials with an excellent attenuation capacity is crucial for the increasingly serious problem of electromagnetic pollution. Herein, FeS/Fe3C/N-doped carbon nanorods (FCS) composites derived from metal-organic frameworks (MOFs) were developed via a facile carbonation-sulfidation strategy. By comparison with the carbonized products (Fe/Fe3C/N-doped carbon composites), the synergistic effect among multiple-components with heterogeneous interface and porous structure of FCS composites balance the impedance matching via reducing the complex permittivity, resulting in FCS composites excellent EMW absorption performance. Among them, the FCS-2 composite exhibits an outstanding EMW attenuation ability of −66.28 dB at only 1.61 mm, and the broad effective absorption bandwidth (EAB) achieves 6.2 GHz at 1.88 mm, covering the entire Ku band. Hence, this work inspires the development of exploring novel high-performance EMW absorption materials via the dual strategy of carbonation-sulfidation.

Enhanced Interfacial Evaporation and Desalination by Solar Heat Localisation Using Nitrogenated Graphitic Carbon and Co3o4 Nanorods

Enhanced Interfacial Evaporation and Desalination by Solar Heat Localisation Using Nitrogenated Graphitic Carbon and Co3o4 Nanorods

Poly(Ionic Liquids) Derived N,S Co-Doped Carbon Nanorod from in Situ and Template-Free Method as an Efficient Metal-Free Bifunctional Electrocatalysts for Direct Methanol Fuel Cells

Poly(Ionic Liquids) Derived N,S Co-Doped Carbon Nanorod from in Situ and Template-Free Method as an Efficient Metal-Free Bifunctional Electrocatalysts for Direct Methanol Fuel Cells

Se/N co-doped carbon nanorods for potassium ion storage

Herein, we make use of the large-sized Se atom to regulate the local structure of the graphitic lattice to optimize N-doping species to strengthen the adsorption of K+, which can greatly boost the capacitive capacity for PIBs.

Metal/nitrogen co-doped hollow carbon nanorods derived from self-assembly organic nanostructure for wide bandwidth electromagnetic wave absorption

Converting carbonaceous material into heteroatom-doped hollow nanomaterial is a promise route to realize lightweight and high-performance electromagnetic wave absorption (EMA). In this work, a series of metal/nitrogen co-doped hollow carbon nanorods (M-NHCRs, M represent as Fe, Co, Ni) were successfully fabricated via a facile self-assembly template strategy, which refers to self-assembling of 9,10-dibromoanthracene (DBA), surficial modification with polydopamine (PDA) and metal ions, and controlled pyrolysis. Among these M-NHCRs, Co-NHCR exhibits remarkable EMA performance, where the optimal reflection loss (RL) reaches −58.6 dB at a loading ratio of 5 wt%. Moreover, the effective absorption bandwidth (EAB) gets to 7.65 GHz. It is considered that the high-performance EMA should be attributed to the unique hollow structure, excellent conductance loss and improved polarization relaxation. This research not only provides a new idea for the design of lightweight electromagnetic absorbents with broadband efficient absorption, but also broadens the way of synthesizing hollow nanomaterials. • Hollow carbon nanorod was constructed by thermally removable self-assembly template. • Doping by trace of metal obviously enhances electromagnetic absorption performance. • Effective absorption bandwidth (EAB) gets to 7.65 GHz at low loading ratio.

Enhanced oxygen evolution catalyzed by in situ formed Fe-doped Ni oxyhydroxides in carbon nanotubes

In this work, rod-like NiOF-1 is synthesized and converted into hollow NiOF-1-Fe with etching effect. After pyrolysis, FeNi3 particles within in situ formed carbon nanotubes on hollow carbon nanorods are proposed as an efficient OER electrocatalyst.