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Construction of 3D porous Cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage
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作者 Chen Chen Hongyu Xue +6 位作者 Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang Yongsong Luo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期191-200,共10页
Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation d... Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific capacities.However,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs anode.Herein,the three-dimensional porous Cu_(1.81)S/nitrogen-doped carbon frameworks(Cu_(1.81)S/NC)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of Cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for SIBs.Moreover,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/C cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 cycles.This work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode. 展开更多
关键词 copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries
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Template-Induced Graphitic Nanodomains in Nitrogen-Doped Carbons Enable High-Performance Sodium-Ion Capacitors
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作者 Chun Li Zihan Song +6 位作者 Minliang Liu Enrico Lepre Markus Antonietti Junwu Zhu Jian Liu Yongsheng Fu Nieves López-Salas 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第4期295-303,共9页
Sodium-ion capacitors(SICs)have great potential in energy storage due to their low cost,the abundance of Na,and the potential to deliver high energy and power simultaneously.This article demonstrates a template-assist... Sodium-ion capacitors(SICs)have great potential in energy storage due to their low cost,the abundance of Na,and the potential to deliver high energy and power simultaneously.This article demonstrates a template-assisted method to induce graphitic nanodomains and micro-mesopores into nitrogen-doped carbons.This study elucidates that these graphitic nanodomains are beneficial for Na+storage.The obtained N-doped carbon(As8Mg)electrode achieved a reversible capacity of 254 mA h g^(-1)at 0.1 A g^(-1).Moreover,the As8Mg-based SIC device achieves high combinations of power/energy densities(53 W kg^(-1)at 224 Wh kg^(-1)and 10410 W kg^(-1)at 51 Wh kg^(-1))with outstanding cycle stability(99.7%retention over 600 cycles at 0.2 A g^(-1)).Our findings provide insights into optimizing carbon’s microstructure to boost sodium storage in the pseudocapacitive mode. 展开更多
关键词 ANODE graphitic nanodomains N-doped carbons sodium-ion capacitor TEMPLATE
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Enhanced stability of nitrogen-doped carbon-supported palladium catalyst for oxidative carbonylation of phenol
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作者 Xiaojing Liu Ruohan Zhao +4 位作者 Hao Zhao Zhimiao Wang Fang Li Wei Xue Yanji Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期19-28,共10页
Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticle... Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and industry.Herein,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen source.The Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F127 addition.The hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd NPs.This process helped to improve metal dispersion.The increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF catalyst.Furthermore,density functional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/NCF during the reaction process.This work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts. 展开更多
关键词 Supported Pd catalyst N-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen STABILITY
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Electronic Communication Between Co and Ru Sites Decorated on Nitrogen-Doped Carbon Nanotubes Boosting the Alkaline Hydrogen Evolution Reaction
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作者 Meng-Ting Gao Ying Wei +8 位作者 Xue-Meng Hu Wenj-Jie Zhu Qing-Qing Liu Jin-Yuan Qiang Wan-Wan Liu Ying Wang Xu Li Jian-Feng Huang Yong-Qiang Feng 《电化学(中英文)》 CAS 北大核心 2024年第9期1-9,共9页
Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic ... Designing highly efficient Pt-free electrocatalysts with low overpotential for an alkaline hydrogen evolution reaction(HER)remains a significant challenge.Here,a novel and efficient cobalt(Co),ruthenium(Ru)bimetallic electrocatalyst composed of CoRu nanoalloy decorated on the N-doped carbon nanotubes(CoRu@N-CNTs),was prepared by reacting fullerenol with melamine via hydrothermal treatment and followed by pyrolysis.Benefiting from the electronic communication between Co and Ru sites,the as-obtained CoRu@N-CNTs catalyst exhibited superior electrocatalytic HER activity.To deliver a current density of 10 mA·cm^(-2),it required an overpotential of merely 19 mV along with a Tafel slope of 26.19 mV·dec^(-1)in 1 mol·L^(-1)potassium hydroxide(KOH)solution,outperforming the benchmark Pt/C catalyst.The present work would pave a new way towards the design and construction of an efficient electrocatalyst for energy storage and conversion. 展开更多
关键词 CoRu alloy ELECTROCATALYST Water splitting Hydrogen evolution reaction carbon nanotubes
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Elucidating the role of embedding dispersed cobalt sites in nitrogen-doped carbon frameworks in Si-based anodes for stable and superior storage
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作者 Yueying Chen Ping Li +8 位作者 Mianying Huang Chunlei Wu Qianhong Huang Tingyang Xie Xiaoming Lin Akif Zeb Yongbo Wu Zhiguang Xu Yuepeng Cai 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期180-195,共16页
Unsatisfactory conductivity and volume effects have hindered the commercial application of siliconbased materials as advanced anode materials for high-performance lithium-ion batteries. Herein, nitrogen doped carbon s... Unsatisfactory conductivity and volume effects have hindered the commercial application of siliconbased materials as advanced anode materials for high-performance lithium-ion batteries. Herein, nitrogen doped carbon silicon matrix composite with atomically dispersed Co sites(Si/Co-N-C) is obtained via the design of the frame structure loaded with nano-components and the multi-element hybrid strategy. Co atoms are uniformly fixed to the N-C frame and tightly packed with nanoscale silicon particles as an activation and protection building block. The mechanism of the N-C framework of loaded metal Co in the Si alloying process is revealed by electrochemical kinetic analysis and ex situ characterization tests.Impressively, the nitrogen-doped Co site activates the intercalation of the outer carbon matrix to supplement the additional capacity. The Co nanoparticles with high conductivity and support enhance the conductivity and structural stability of the composite, accelerating the Li^(+)/Na^(+) diffusion kinetics. Density functional theory(DFT) calculation confirms that the hetero-structure Si/Co-N-C adjusts the electronic structure to obtain good lithium-ion adsorption energy, reduces the Li^(+)/Na^(+) migration energy barrier.This work provides meaningful guidance for the development of high-performance metal/non-metal modified anode materials. 展开更多
关键词 Co nanoparticles Nitrogen doped carbon Silicon Lithium/sodium storage Metal-organic frameworks(MOFs)
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Engineering single-atom Mn on nitrogen-doped carbon to regulate lithium-peroxide reaction kinetics for rechargeable lithium-oxygen batteries
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作者 Yaling Huang Yong Liu +3 位作者 Yang Liu Chenyang Zhang Wenzhang Li Jie Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期199-207,共9页
Precision engineering of catalytic sites to guide more favorable pathways for Li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-it... Precision engineering of catalytic sites to guide more favorable pathways for Li_(2)O_(2) nucleation and decom-position represents an enticing kinetic strategy for mitigating overpotential,enhancing discharge capac-ity,and improving recycling stability of Li-O_(2) batteries.In this work,we employ metal-organic frameworks(MOFs)derivation and ion substitution strategies to construct atomically dispersed Mn-N_(4) moieties on hierarchical porous nitrogen-doped carbon(Mn SAs-NC)with the aim of reducing the over-potential and improving the cycling stability of Li-O_(2) batteries.The porous structure provides more chan-nels for mass transfer and exposes more highly active sites for electrocatalytic reactions,thus promoting the formation and decomposition of Li_(2)O_(2).The Li-O_(2) batteries with Mn SAs-NC cathode achieve lower overpotential,higher specific capacity(14290 mA h g^(-1) at 100 mAg^(-1)),and superior cycle stability(>100 cycles at 200 mA g^(-1))compared with the Mn NPs-NC and NC.Density functional theory(DFT)cal-culations reveal that the construction of Mn-N_(4) moiety tunes the charge distribution of the pyridinic N-rich vacancy and balances the affinity of the intermediates(LiO_(2) and Li_(2)O_(2)).The initial nucleation of Li_(2)O_(2) on Mn SAs-NC favors the O_(2)-→LiO_(2)→Li_(2)O_(2) surface-adsorption pathway,which mitigates the overpoten-tials of the oxygen reduction(ORR)and oxygen evolution reaction(OER).As a result,Mn SAs-NC with Mn-N_(4) moiety effectively facilitates the Li_(2)O_(2) nucleation and enables its reversible decomposition.This work establishes a methodology for constructing carbon-based electrocatalysts with high activity and selectivity for Li-O_(2)batteries. 展开更多
关键词 Single-atom Mn MOFs-oriented architecture Rechargeable Li-O_(2)battery N-doped carbon Density functional theory calculation
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High-performance Pt catalysts supported on hierarchical nitrogen-doped carbon nanocages for methanol electrooxidation 被引量:5
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作者 蒋湘芬 王学斌 +5 位作者 沈丽明 吴强 王秧年 马延文 王喜章 胡征 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第7期1149-1155,共7页
Hierarchical nitrogen-doped carbon nanocages (hNCNC) with large specific surface areas were used as a catalyst support to immobilize Pt nanoparticles by a microwave-assisted polyol method. The Pt/hNCNC catalyst with... Hierarchical nitrogen-doped carbon nanocages (hNCNC) with large specific surface areas were used as a catalyst support to immobilize Pt nanoparticles by a microwave-assisted polyol method. The Pt/hNCNC catalyst with 20 wt% loading has a homogeneous dispersion of Pt nanoparticles with the average size of 3.3 nm, which is smaller than 4.3 and 4.9 nm for the control catalysts with the same loading supported on hierarchical carbon nanocages (hCNC) and commercial Vulcan XC-72, respec- tively. Accordingly, Pt/hNCNC has a larger electrochemical surface area than Pt/hCNC and Pt/XC-72. The Pt/hNCNC catalyst exhibited excellent electrocatalytic activity and stability for methanol oxidation, which was better than the control catalysts. This was attributed to the en- hanced interaction between Pt and hNCNC due to nitrogen participation in the anchoring function. By making use of the unique advantages of the hNCNC support, a heavy Pt loading up to 60 wt% was prepared without serious agglomeration, which gave a high peak-current density per unit mass of catalyst of 95.6 mA/mg for achieving a high power density. These results showed the potential of the Pt/hNCNC catalyst for methanol oxidation and of the new hNCNC support for wide applications. 展开更多
关键词 Methanol oxidationFuel cellsPlatinum catalystHierarchical nitrogen-doped carbon nanocagesHigh performance
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Preparation of nitrogen-doped carbon nanoblocks with high electrocatalytic activity for oxygen reduction reaction in alkaline solution 被引量:2
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作者 张亭亭 何传生 +1 位作者 黎琳波 林雨青 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1275-1282,共8页
The oxygen reduction reaction (ORR) is traditionally performed using noble‐metals catalysts, e.g. Pt. However, these metal‐based catalysts have the drawbacks of high costs, low selectivity, poor stabili‐ties, and... The oxygen reduction reaction (ORR) is traditionally performed using noble‐metals catalysts, e.g. Pt. However, these metal‐based catalysts have the drawbacks of high costs, low selectivity, poor stabili‐ties, and detrimental environmental effects. Here, we describe metal‐free nitrogen‐doped carbon nanoblocks (NCNBs) with high nitrogen contents (4.11%), which have good electrocatalytic proper‐ties for ORRs. This material was fabricated using a scalable, one‐step process involving the pyrolysis of tris(hydroxymethyl)aminomethane (Tris) at 800℃. Rotating ring disk electrode measurements show that the NCNBs give a high electrocatalytic performance and have good stability in ORRs. The onset potential of the catalyst for the ORR is-0.05 V (vs Ag/AgCl), the ORR reduction peak potential is-0.20 V (vs Ag/AgCl), and the electron transfer number is 3.4. The NCNBs showed pronounced electrocatalytic activity, improved long‐term stability, and better tolerance of the methanol crosso‐ver effect compared with a commercial 20 wt%Pt/C catalyst. The composition and structure of, and nitrogen species in, the NCNBs were investigated using Fourier‐transform infrared spectroscopy, scanning electron microscopy, X‐ray photoelectron spectroscopy, and X‐ray diffraction. The pyroly‐sis of Tris at high temperature increases the number of active nitrogen sites, especially pyridinic nitrogen, which creates a net positive charge on adjacent carbon atoms, and the high positive charge promotes oxygen adsorption and reduction. The results show that NCNBs prepared by pyrolysis of Tris as nitrogen and carbon sources are a promising ORR catalyst for fuel cells. 展开更多
关键词 nitrogen-doped carbon nanoblock Trihydroxymethyl aminomethane ELECTROCATALYST Oxygen reduction reaction NANOCATALYST
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Hierarchically porous nitrogen-doped carbon as cathode for lithium–sulfur batteries 被引量:11
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作者 Rui Wu Siguo Chen +5 位作者 Jianghai Deng Xun Huang Yujie Song Ruiyi Gan Xiaoju Wan Zidong Wei 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第6期1661-1667,共7页
Porous nitrogen-doped carbon is an especially promising material energy storage due to its excellentconductivity, stable physicochemical properties, easy processability, controllable porosity and low price.Herein, we ... Porous nitrogen-doped carbon is an especially promising material energy storage due to its excellentconductivity, stable physicochemical properties, easy processability, controllable porosity and low price.Herein, we reported a novel well-designed hierarchically porous nitrogen-doped carbon (HPNC) via acombination of salt template (ZnC12) and hard template (SiO2) as sulfur host for lithium-sulfur batter-ies. The low-melting ZnC12 is boiled off and leaves behind micropores and small size mesopores duringpyrolysis process, while the silica spheres are removed by acid leaching to generate interconnected 3Dnetwork of macropores. The HPNC-S electrode exhibits an initial specific capacity of 1355 mAh g^-l at 0.IC (IC= 1675 mAh g^-1 ), a high-rate capability of 623 mAh g-l at 2 C, and a small decay of 0.13% per cycleover 300 cycles at 0.2 C. This excellent rate capability and remarkable long-term cyclability of the HPNC-Selectrode are attributed to its hierarchical porous structures for confining the soluble lithium polysulfideas well as the nitrogen doping for high absorbability of lithium polysulfide. 展开更多
关键词 Hierarchically porous structure nitrogen-doped carbon Lithium-sulfur batteries
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Electrocatalytic hydrogen peroxide formation on mesoporous non-metal nitrogen-doped carbon catalyst 被引量:6
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作者 Frédéric Hasché Mehtap Oezaslan +1 位作者 Peter Strasser Tim-Patrick Fellinger 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2016年第2期249-255,共7页
Direct electrochemical formation of hydrogen peroxide(H2O2) from pure O2 and H2on cheap metal-free earth abundant catalysts has emerged as the highest atom-efficient and environmentally friendly reaction pathway and... Direct electrochemical formation of hydrogen peroxide(H2O2) from pure O2 and H2on cheap metal-free earth abundant catalysts has emerged as the highest atom-efficient and environmentally friendly reaction pathway and is therefore of great interest from an academic and industrial point of view. Very recently,novel metal-free mesoporous nitrogen-doped carbon catalysts have attracted large attention due to the unique reactivity and selectivity for the electrochemical hydrogen peroxide formation [1–3]. In this work,we provide deeper insights into the electrocatalytic activity, selectivity and durability of novel metal-free mesoporous nitrogen-doped carbon catalyst for the peroxide formation with a particular emphasis on the influence of experimental reaction parameters such as p H value and electrode potential for three different electrolytes. We used two independent approaches for the investigation of electrochemical hydrogen peroxide formation, namely rotating ring-disk electrode(RRDE) technique and photometric UV–VIS technique. Our electrochemical and photometric results clearly revealed a considerable peroxide formation activity as well as high catalyst durability for the metal-free nitrogen-doped carbon catalyst material in both acidic as well as neutral medium at the same electrode potential under ambient temperature and pressure. In addition, the obtained electrochemical reactivity and selectivity indicate that the mechanisms for the electrochemical formation and decomposition of peroxide are strongly dependent on the p H value and electrode potential. 展开更多
关键词 Electrochemical hydrogen peroxide FORMATION SELECTIVITY Mesoporous nitrogen-doped carbon Green synthesis ELECTROCATALYSIS Metal-free catalysis
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Effects of Potassium and Manganese Promoters on Nitrogen-Doped Carbon Nanotube-Supported Iron Catalysts for CO_2 Hydrogenation 被引量:6
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作者 Praewpilin Kangvansura Ly May Chew +6 位作者 Chanapa Kongmark Phatchada Santawaja Holger Ruland Wei Xia Hans Schulz Attera Worayingyong Martin Muhler 《Engineering》 SCIE EI 2017年第3期385-392,共8页
Nitrogen-doped carbon nanotubes (NCNTs) were used as a support for iron (Fe) nanoparticles applied in car- bon dioxide (CO_2) hydrogenation at 633 K and 25 bar (1 bar = 10-5 Pa). The Fe/NCNT catalyst promoted ... Nitrogen-doped carbon nanotubes (NCNTs) were used as a support for iron (Fe) nanoparticles applied in car- bon dioxide (CO_2) hydrogenation at 633 K and 25 bar (1 bar = 10-5 Pa). The Fe/NCNT catalyst promoted with both potassium (K) and manganese (Mn) showed high performance in CO_2 hydrogenation, reaching 34.9% conversion with a gas hourly space velocity (GHSV) of 3.1 L-(g·h)-1. Product selectivities were high for olefin products and low for short-chain alkanes for the K-promoted catalysts. When Fe/NCNT catalyst was promot- ed with both K and Mn, the catalytic activity was stable for 60 h of reaction time. The structural effect of the Mn promoter was demonstrated by X-ray diffraction (XRD), temperature-programmed reduction (TPR) with molecular hydrogen (H2), and in situ X-ray absorption near-edge structure (XANES) analysis. The Mn pro- moter stabilized wtistite (FeO) as an intermediate and lowered the TPR onset temperature. Catalytic ammo- nia (NH_3) decomposition was used as an additional probe reaction for characterizing the promoter effects. The Fe/NCNT catalyst promoted with both K and Mn had the highest catalytic activity, and the Mn-promoted Fe/NCNT catalysts had the highest thermal stability under reducing conditions. 展开更多
关键词 CO_2 hydrogenation Iron catalyst nitrogen-doped carbon nanotubes Manganese promoter Potassium promoter
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Nitrogen-doped carbon nanotube encapsulating cobalt nanoparticles towards efficient oxygen reduction for zinc–air battery 被引量:4
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作者 Haihua Wu Xiaole Jiang +5 位作者 Yifan Ye Chengcheng Yan Songhai Xie Shu Miao Guoxiong Wang Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1181-1186,共6页
Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt s... Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt substituted perfluorosulfonic acid/polytetrafluoroethylene copolymer and dicyandiamide as the pyrolysis precursor to synthesize nitrogen-doped carbon nanotube(N–CNT) encapsulating cobalt nanoparticles hybrid material. The carbon layers and specific surface area of N–CNT have a critical role to the ORR performance due to the exposed active sites, determined by the mass ratio of the two precursors. The optimum hybrid material exhibits high ORR activity and stability, as well as excellent performance and durability in zinc–air battery. 展开更多
关键词 nitrogen-doped carbon nanotube Perfluorosulfonic Acid/polytetrafluoroethylene copolymer Cobalt substitution Oxygen reduction reaction Zinc–air battery
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Novel Co_3O_4 Nanoparticles/Nitrogen-Doped Carbon Composites with Extraordinary Catalytic Activity for Oxygen Evolution Reaction(OER) 被引量:4
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作者 Xiaobing Yang Juan Chen +4 位作者 Yuqing Chen Pingjing Feng Huixian Lai Jintang Li Xuetao Luo 《Nano-Micro Letters》 SCIE EI CAS 2018年第1期137-147,共11页
Herein, Co_3O_4 nanoparticles/nitrogen-doped carbon(Co_3O_4/NPC) composites with different structures were prepared via a facile method. Structure control was achieved by the rational morphology design of ZIF-67 precu... Herein, Co_3O_4 nanoparticles/nitrogen-doped carbon(Co_3O_4/NPC) composites with different structures were prepared via a facile method. Structure control was achieved by the rational morphology design of ZIF-67 precursors, which were then pyrolyzed in air to obtain Co_3O_4/NPC composites. When applied as catalysts for the oxygen evolution reaction(OER), the M-Co_3O_4/NPC composites derived from the flower-like ZIF-67 showedsuperior catalytic activities than those derived from the rhombic dodecahedron and hollow spherical ZIF-67. The former M-Co_3O_4/NPC composite displayed a small overpotential of 0.3 V, low onset potential of 1.41 V, small Tafel slope of 83 m V dec^(-1), and a desirable stability.(94.7% OER activity was retained after 10 h.) The excellent performance of the flower-like M-Co_3O_4/NPC composite in the OER was attributed to its favorable structure. 展开更多
关键词 Co3O4 nanoparticles nitrogen-doped carbon ZIF-67 CATALYTIC Oxygen evolution reaction(OER)
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Nitrogen-doped carbon encapsulated in mesoporous TiO2 nanotubes for fast capacitive sodium storage 被引量:3
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作者 Baosong Li Shoaib Anwer +3 位作者 Xinhua Huang Shaohong Luo Jing Fu Kin Liao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第4期202-210,共9页
Controllable synthesis of insertion-type anode materials with beneficial micro-and nanostructures is a promising approach for the synthesis of sodium-ion storage devices with high-reactivity and excellent electrochemi... Controllable synthesis of insertion-type anode materials with beneficial micro-and nanostructures is a promising approach for the synthesis of sodium-ion storage devices with high-reactivity and excellent electrochemical performance.In this study,we developed a sacrificial-templating route to synthesize TiO_(2)@N-doped carbon nanotubes(TiO_(2)@NC-NTs)with excellent electrochemical performance.The asprepared mesoporous TiO_(2)@NC-NTs with tiny nanocrystals of anatase TiO_(2) wrapped in N-doped carbon layers showed a well-defined tube structure with a large specific surface area of 198 m^(2) g^(-1) and a large pore size of~5 nm.The TiO_(2)@NC-NTs delivered high reversible capacities of 158 m A h g^(-1) at 2 C(1 C=335 m A g^(-1))for 2200 cycles and 146 m A h g^(-1) at 5 C for 4000 cycles,as well as an ultrahigh rate capability of up to 40 C with a capacity of 98 m A h g^(-1).Even at a high current density of 10 C,a capacity of 138 m A h g^(-1) could be delivered over 10,000 cycles.Thus,the synthesis of mesoporous TiO_(2)@NC-NTs was demonstrated to be an efficient approach for developing electrode materials with high sodium storage and long cycle life. 展开更多
关键词 TiO2 nanotubes MoO3 template nitrogen-doped carbon ANODE Sodium-ion battery
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Nitrogen-Doped Carbon Nanotube-Supported Pd Catalyst for Improved Electrocatalytic Performance toward Ethanol Electrooxidation 被引量:3
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作者 Ying Wei Xinyuan Zhang +4 位作者 Zhiyong Luo Dian Tang Changxin Chen Teng Zhang Zailai Xie 《Nano-Micro Letters》 SCIE EI CAS 2017年第3期43-51,共9页
In this study, hydrothermal carbonization(HTC)was applied for surface functionalization of carbon nanotubes(CNTs) in the presence of glucose and urea. The HTC process allowed the deposition of thin nitrogen-doped carb... In this study, hydrothermal carbonization(HTC)was applied for surface functionalization of carbon nanotubes(CNTs) in the presence of glucose and urea. The HTC process allowed the deposition of thin nitrogen-doped carbon layers on the surface of the CNTs. By controlling the ratio of glucose to urea, nitrogen contents of up to 1.7 wt%were achieved. The nitrogen-doped carbon nanotube-supported Pd catalysts exhibited superior electrochemical activity for ethanol oxidation relative to the pristine CNTs.Importantly, a 1.5-fold increase in the specific activity was observed for the Pd/HTC-N1.67%CNTs relative to the catalyst without nitrogen doping(Pd/HTC-CNTs). Furtherexperiments indicated that the introduction of nitrogen species on the surface of the CNTs improved the Pd(0)loading and increased the binding energy. 展开更多
关键词 Direct alcohol fuel cells Hydrothermal carbonization nitrogen-doped carbon nanotubes Pdbased catalyst Ethanol electrocatalyst
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Ultrafine VN nanodots induced generation of abundant cobalt single-atom active sites on nitrogen-doped carbon nanotube for efficient hydrogen evolution 被引量:2
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作者 Yan Cheng Juhui Gong +7 位作者 Bo Cao Xuan Xu Peng Jing Shien-Ping Feng Rui Cheng Baocang Liu Rui Gao Jun Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第5期646-657,共12页
Development of highly active and stable non-noble electrocatalysts with well-defined nanostructures is crucial for efficient hydrogen evolution reaction(HER). Herein, a novel three-dimensional(3D) selfsupported electr... Development of highly active and stable non-noble electrocatalysts with well-defined nanostructures is crucial for efficient hydrogen evolution reaction(HER). Herein, a novel three-dimensional(3D) selfsupported electrode consists of vanadium nitride(VN) nanodots and Co nanoparticles co-embedded and highly active single Co atoms anchored in N-doped carbon nanotubes supported on carbon cloth(VN-Co@CoSAs-NCNTs/CC) is fabricated via a one-step in situ nanoconfined pyrolysis strategy, which shows remarkable enhanced HER electrocatalytic activity in acidic medium. During pyrolysis, the formed VN nanodots induce the generation of atomic Co Nxsites in NCNTs, contributing to superior electrocatalytic activity. Experimental and density functional theory(DFT) calculation results reveal that the electrode has multiple accessible active sites, fast reaction kinetics, low charge/mass transfer resistances,high conductivity, as well as downshifted d-band center with a thermodynamically favorable hydrogen adsorption free energy(△G_(H·)), all of which greatly boost the HER performance. As a result, the VNCo@CoSAs-NCNTs/CC electrode displays superb catalytic performance toward HER with a low overpotential of 29 mV at 10 mA cm^(-2) in acidic medium, which could maintain for at least 60 h of stable performance. This work opens a facile avenue to explore low-cost, high performance, but inexpensive metals/nitrogen-doped carbon composite electrocatalysts for HER. 展开更多
关键词 Single cobalt atoms nitrogen-doped carbon nanotubes Vanadium nitride nanodots Cobalt nanoparticles Hydrogen evolution reaction
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A correlation between structural changes in a Ni-Cu catalyst during decomposition of ethylene/ammonia mixture and properties of nitrogen-doped carbon nanofibers 被引量:1
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作者 O. Yu. Podyacheva A. N. Shmakov +4 位作者 A. I. Boronin L. S. Kibis S. V. Koscheev E. Yu. Gerasimov Z. R. Ismagilov 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第2期270-278,共9页
Changes of a 65Ni25Cu10A1203 catalyst consisting of Ni-enriched and Cu-enriched alloys were investigated in the bulk and on the surface during the growth of nitrogen-doped carbon nanofibers (N-CNFs) by decomposition... Changes of a 65Ni25Cu10A1203 catalyst consisting of Ni-enriched and Cu-enriched alloys were investigated in the bulk and on the surface during the growth of nitrogen-doped carbon nanofibers (N-CNFs) by decomposition of a 50%C2I-I4/50%NH3 mixture using in situ X-ray diffraction (XRD) analysis, ex situ X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) techniques. It was shown that N-CNF growth at 450-650 ℃is accompanied by dissolution of carbon and nitrogen in the Ni-enriched alloy, whereas Cu-enriched alloy remains inactive. A correlation between nickel and copper surface concentrations and properties of N-CNFs in relation to the nitrogen content was found. It was demonstrated that phase composition of the catalyst during N-CNF growth determines the type of N-CNFs structure. 展开更多
关键词 carbon nanofibers nitrogen-doped carbon nanofibers XRD in situ XPS CATALYST
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Robust copper nanocrystal/nitrogen-doped carbon monoliths as carbon monoxide-resistant electrodes for methanol oxidation reaction 被引量:1
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作者 Fei Chen Na Wu +4 位作者 Meixu Zhai Xue Zhang Ruihong Guo Tuoping Hu Mingming Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期247-255,共9页
Noble metal-based electrocatalysts present high activities for methanol oxidation reaction(MOR),but are limited by their high cost,low stability and poor resistance to carbon monoxide(CO) poisoning.The development of ... Noble metal-based electrocatalysts present high activities for methanol oxidation reaction(MOR),but are limited by their high cost,low stability and poor resistance to carbon monoxide(CO) poisoning.The development of active and stable non-noble metal electrocatalysts for MOR is desired,but remains a challenge.Herein,we report a simple strategy to make copper nanocrystal/nitrogen-doped carbon(Cu/N-C)monoliths,which can serve as active and robust electrodes for MOR.Copper nanocrystals were electrochemically deposited onto a conductive polyaniline hydrogel and calcined to form Cu/N-C monolith,where the active copper nanocrystals are protected by nitrogen-doped carbon.Owing to their extremely high electrical conductivity(1.25 × 10^(5) S cm^(-1)) and mechanical robustness,these Cu/N-C monoliths can be directly used as electrodes for MOR,without using substrates or additives.The optimal Cu/N-C(FT)@500 monolith shows a high MOR activity of 189 mA cm^(-2) at 0.6 V vs.SCE in alkaline methanol solution,superior to most of reported Cu-based MOR catalysts.Cu/N-C(FT)@500 also presents a better stability than Pt/C catalyst in the long-term MOR test at high current densities.Upon carbon monoxide(CO) poisoning,Cu/N-C(FT)@500 retains 96% of its MOR activity,far exceeding the performance of Pt/C catalyst(61% retention).Owing to its facile synthesis,outstanding activity,high stability and mechanical robustness,Cu/N-C(FT)@500 monolith is promising as a low-cost,efficient and CO-resistant electrocatalyst for MOR. 展开更多
关键词 Copper nanocrystal Methanol oxidation reaction Non-noble metal-based electrocatalysts Poison-resistant electrocatalysts nitrogen-doped carbon
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Pre-fixing defects in carbon framework for revealing the active sites of oxygen reduction reaction at nitrogen-doped carbon nanotubes 被引量:1
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作者 Bing Huang Kun Hou +2 位作者 Yang Liu Rongtao Hu Lunhui Guan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期521-527,I0012,共8页
Nitrogen-doped carbon-based materials are promising non-platinum group metal electrocatalysts for the oxygen reduction reaction(ORR).Understanding their ORR active sites is vital for the rational design and developmen... Nitrogen-doped carbon-based materials are promising non-platinum group metal electrocatalysts for the oxygen reduction reaction(ORR).Understanding their ORR active sites is vital for the rational design and development of nitrogen-doped carbon-based electrocatalysts with enhanced catalytic efficiency and selectivity.However,the conclusive analysis of the ORR mechanism of nitrogen-doped carbon-based electrocatalysts remains a grand challenge because the catalysts have a complex inhomogeneous structure.Here,we elucidate this problem using nitrogen-doped carbon nanotubes framework catalysts with fixed defect concentrations prepared by pre-thermal treatment at a low temperature.The generation of defects under high-temperature treatment was effectively suppressed to enable a simple model for ORR mechanism study.A correlation between ORR pathways and the different nitrogen species in the nitrogen-doped carbon catalysts was revealed through a combination of structural and electrochemical properties investigations.Besides,our results also demonstrate the importance of defects for ORR.We believe that the results will provide instructive guidance for designing and developing novel carbon nanomaterials for ORR. 展开更多
关键词 ELECTROCATALYSTS Oxygen reduction reaction DEFECTS nitrogen-doped carbon nanotube
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Metallurgical pyrolysis toward Co@Nitrogen-doped carbon composite for lithium storage 被引量:1
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作者 Yanyan Liu Kang Sun +4 位作者 Jianchun Jiang Wenshu Zhou Yuan Shang Chenxia Du Baojun Li b 《Green Energy & Environment》 SCIE CSCD 2021年第1期91-101,共11页
Elemental state matter-heteroatom-doped carbon composites are of great importance for the development of anode in lithium ion batteries(LIBs).In this article,metal–organic frameworks(MOFs)are adopted as precursor to ... Elemental state matter-heteroatom-doped carbon composites are of great importance for the development of anode in lithium ion batteries(LIBs).In this article,metal–organic frameworks(MOFs)are adopted as precursor to prepare Co composites via metallurgical pyrolysis under controllable conditions.The obtained nitrogen-doped porous carbon-Co nanocomposite possesses core–shell structure(Co@C–N).Co@C–N exhibits the best Li storage performances as anode active matter.After the 200th cycles at current density of 0.2 A g^(-1),a reversible capacity of 870 mAh g^(-1)is retained.A reversible capacity of 275 mAh g^(-1)still maintains with 5 A g^(-1).Co@C–N presents a high reversible capacity with excellent cycle stability.Considering the corresponding experimental and theoretical results,the Co0-based N-doped porous carbon composite is proposed to work as LIBs anode matter.These results provide a new design idea for electrode matters of metallic ion battery,and demonstrate that MOFs pyrolysis is an effective method for the construction of elemental state anode materials. 展开更多
关键词 Co nanoparticles(NPs) Core–shell structure Lithium ion battery anode Metal–organic framework(MOF) nitrogen-doped carbon
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