JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2019
·
IF 3.218
Sumbal Farid,Weiwei Qiu,Jialin Zhao,Xuedan Song,Qing Mao,Suzhen Ren,Ce Hao
In recent years, a noticeable shifting from conventional fossil fuels to renewable energy based systems has embarked electrochemical splitting of water as the most promising way to produce clean energy of hydrogen. Generally, the lack of active and stable electrocatalysts for oxygen evolution reaction (OER) limits the practicability of water splitting as a renewable source of energy. In this work, interconnected 3D structure of cobalt oxides nanoparticles (Co 3 O 4 NPs) derived from ZIF-67 with nitrogen-doped carbon nanotubes (N-CNTs) of polypyrrole (PPy) origin is successfully synthesized as OER electrocatalysts. Impressively, the highly conductive N-CNTs that run through the Co 3 O 4 NPs not only endow the resulting product Co 3 O 4 /N-CNTs with large active surface area and enhanced charge transfer between Co 3 O 4 NPs, but also prevent Co 3 O 4 NPs from aggregation. As a result, the as-synthesized Co 3 O 4 /N-CNTs electrocatalyst exhibits outstanding OER activity with a low onset potential of ~1.37 V (vs RHE), overpotential of only 200 mV to attain a stable current density of 10 mA cm − 2 in basic media and very small Tafel slope of 40 mV dec − 1 . Moreover, the enhanced nitrogen-content also improves the OER kinetics by proficient charge transfer. The superb electrocatalytic performance and higher stability make the Co 3 O 4 /N-CNTs a proficient non-precious electrocatalyst for the OER.
研究领域:
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2020
·
IF 4.939
Li Wang,Lili Cui,Xin Ge,Nailin Yue,Xingquan He,Wei Zhang,Tewodros Asefa
Developing efficient nonprecious electrocatalysts that can drive the oxygen electrode reactions in zinc-air batteries (ZABs) is important but remains challenging. In this work, novel materials comprising Mn/Cu nanoclusters-grafted N-doped carbon nanotubes are synthesized by preparing and then pyrolyzing Mn/Cu polyphthalocyanine-encapsulated carbon nanotubes (CNTs), followed by treating the products with acidic solution. The materials are named CNTs@(Mn,Cu)PPc-T, where T denotes the pyrolysis temperature in °C, and they are demonstrated to serve as efficient oxygen electrode catalysts for zinc-air batteries (ZABs). Among them, the one synthesized at 900 °C, CNTs@(Mn,Cu)PPc-900, requires more positive onset and half-wave potentials for reduction of oxygen and a low overpotential for the evolution of oxygen. A rechargeable ZAB assembled with CNTs@(Mn,Cu)PPc-900 electrocatalyst delivers a high power density (158.5 mW cm −2 ) and displays an excellent stability in 200 cycles of charge/discharge (in over 33 h). Such performance is even superior to that of a ZAB containing the benchmark Pt/C + RuO 2 catalyst as an air cathode under identical testing condition.
研究领域:
材料科学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2022
·Vol. 12
·期 30
·19022-19028
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IF 4.036
Bin Li,Xiaojia Xu,Zhigang Hu,Yongjing Li,Mengjing Zhou,Jizhen Liu,Yajun Jiang,Peng Wang
Deep eutectic solvent (DES) was prepared by using acrylic acid (AA) and acrylamide (AM) as hydrogen bonding donors (HBD) and choline chloride (ChCl) as hydrogen bonding receptors (HBA). Nitrogen-doped carbon nanotubes (N-CNTs) were dispersed in DES as fillers, and N-CNTs/P(AA-co-AM) composite hydrogels were prepared by FP. The interaction mode between the hydrogel and N-CNTs was characterized by Fourier infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The mechanical properties, pH response and electrical conductivity of the composite hydrogels were studied. The results showed that the mechanical properties of the hydrogel were significantly enhanced with the increase of N-CNT content. The tensile strength and compressive strength of the FP4 composite hydrogel reached 5.42 MPa and 4.29 MPa, respectively. Due to the dissociation of carboxyl groups in AA in an alkaline environment the composite hydrogel showed excellent pH response performance. The conductivity of the hydrogel was also found to be improved with the content of N-CNTs. When the content of N-CNTs is 1.0 wt%, the conductivity of the hydrogel was 4.2 times higher than that of the hydrogel without N-CNTs, and connecting it to a circuit can make an LED lamp emit bright light. In this study, a simple and green method was proposed to prepare composite hydrogels with excellent mechanical properties and electrical conductivity by FP of DES in less than 5 min.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2023
·
IF 13.1
Baojun Wang,Zijie Xu,Hao Wu,Fangzhi Huang,Fenghua Liu,Shikuo Li,Hui Zhang
Multilayered Ti 3 C 2 T x MXene , due to its tunable dielectric constants and structural designability, has been identified as rising star for exploring high-efficiency electromagnetic wave absorbers. However, it is still a huge challenge to address insufficient external contact of multilayered MXene at lower filler loading. Herein, inspired by the layer-pillar-layer architecture, a controllable catalytic-assisted nitrogen-doped carbon nanotubes bridging strategy is rationally proposed on the interlaminations of multilayered MXene units (MXene/TiO 2 /NCNTs, denoted as MTNC) to enhance dielectric dissipation ability. Through chemical vapor deposition , the NCNTs bridges as pillars not only break the confinement effect of multilayered MXene architecture like the process of seed germination but also effectively optimize impedance matching and increase dielectric constants. Simultaneously, the unique NCNTs-encapsulated magnetic components successfully prevents the agglomerations of CoNi nanoparticles and local mismatching problems, which facilitates the construction of three-dimensional magnetic coupling network. Specifically, the N heteroatoms and formed TiO 2 species induce dielectric polarization and corresponding relaxation processes. Driven by unique layer-pillar-layer architecture, optimized impedance matching, and synergistic dielectric-magnetic dissipation capabilities, the resultant absorber delivers outstanding reflection loss value of −55.8 dB and broad absorption bandwidth of 5.88 GHz. This work provides a novel structural design strategy and enlightenment for developing high-performance multilayered MXene-based absorbers.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2024
·
IF 4.3
Yu Wang,Yanling Wang,Yunmei Du,Yanru Liu,Volodymyr Turkevych,Lei Wang
Transition metal nitrides (TMNs) have attracted great attention as ideal active materials in the field of electrocatalysts in recent years due to their excellent electrical conductivity, wide band gap and adjustable morphology. Pure phase Co 4 N nanoparticles encapsulated nitrogen-doped carbon (NC) nanotubes (Co 4 N@NC) were in-situ synthesized by one-pot method. In this paper, the morphology of carbon nanotubes is controlled by adjusting the pyrolysis time, so that more active sites are exposed on carbon nanotubes. Thus, the cobalt nitride catalyst with excellent catalytic performance for hydrogen evolution reaction (HER) in acidic electrolyte was obtained. In summary, due to the protection of mesoporous nitrogen-doped carbon to Co 4 N nanoparticles, large electrochemically active surface area, good conductivity and more exposed active sites, Co 4 N@NC possesses excellent HER performance in acidic electrolytes. The overpotential of Co 4 N@NC at the current density of 10 mA cm −2 is 117 mV (η 10 ), and it shows long-term stability in 0.5 M H 2 SO 4 solution for 50 h. This study provides a strategy for the development of catalysts for the controllable synthesis of high-performance transition metal nitrides.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Heliyon
·
2024
·
IF 3.4
Jun Dong,Qiqi Jiao,Hao Wang,Hong Wang,Yi-ke Ren
The shortcomings of precious metal based catalysts have limited the development of novel energies. So, developing low-cost and high performance transition metal based catalysts is one of the most feasible way to substitute the precious metal based catalysts. In all of the developed catalysts for oxygen reduction reactions (ORR), the iron-based nitrogen doped carbon nanotube (N-CNT) show great promise. In this paper, N-CNT with Fe 3 C encapsulated based catalysts (Fe 3 C@N-CNT) were synthesized. The encapsulation structure of Fe 3 C@N-CNT was confirmed by HAADF-STEM, XANES, XPS, XRD, SEM and other methods. XANES tests show that the doped nitrogen of Fe 3 C changed the length of Fe-C bond and furtherly influenced the electron transfer between encapsulated Fe 3 C and outer layer N-CNT. Electrochemical tests showed that the half-wave potential and onset potential ORR of 750 °C calcined Fe 3 C@N-CNT were 90 mV higher than that of 20 wt% Pt/C. The additional electric field between Fe 3 C and N-CNT modulated the C-N bond of surface N-CNT and enhanced the catalytic performance for ORR. This paper reveal that constructing encapsulated additional electron providing center is an effective way to design high performance catalysts.
研究领域:
材料科学
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电化学
·
催化材料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2025
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IF 5.4
Wei Xia,Congling Li,Li Zhang,Xuemin Yu,Li Zheng,Rui Liu,Aifeng Lv
The development of highly efficient electrocatalysts is of utmost importance for advancing electrochemical energy conversion technologies. Transition metal sulfide heterostructure electrocatalysts have been widely studied and applied in electrocatalysis due to their highly inherent activity in the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at the interface. We prepared NiS 2 /CoS 2 nanoparticle heterostructures doped with nitrogen-carbon nanotubes (CoS 2 /NiS 2 @N-CNTs) to induce the formation of bifunctional reaction sites. This design contributes to the excellent catalytic activity for electrocatalytic water splitting. The CoS 2 /NiS 2 @N-CNTs electrocatalyst exhibits prominent catalytic activities toward HER and OER, which required low overpotentials of 126 and 205 mV to yield the current density of 10 mA cm −2 in 1 M KOH. The prepared electrocatalysts exhibit fast reaction kinetics with tafel slopes of 71 and 82 mV dec −1 in HER and OER, respectively. The catalyst has a larger electrochemically active surface area (ECSA) of 1030 cm −2 and a strong electron transfer capability with an electrochemical impedance of 41 Ω. These properties are mainly attributed to the unique heterogeneous structure of the catalyst. In addition, CoS 2 /NiS 2 @N-CNTs catalyst is used as both the cathode and anode to fabricate a two-electrode system in a 1.0 M KOH solution measured at 1.53 V. Meanwhile, the stability measurement maintains for 23 h at a current density of 10 mA cm −2 with negligible degradation. This work has successfully developed an approach for rational design and novel synthesis of metal sulfide hybrids as bifunctional electrocatalysts with high activity and stability for overall water splitting.
研究领域:
材料科学
·
电化学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Electrocatalysis
·
2017
·Vol. 9
·期 2
·264-270
·
IF 2.398
Zhang Lulu,Chen Yongting,Zhao Pingping,Luo Wei,Chen Shengli,Shao Minhua
One of the main challenges to generate hydrogen is to develop cheap and highly active electrocatalysts toward hydrogen evolution reaction (HER). Herein, Fe 3 C nanorods encapsulated in N-doped carbon nanotubes (Fe 3 C@NCNT) were synthesized by a simple method involving the pyrolysis of a Fe-based metal organic framework (MOF) and melamine. The hybrid composite showed an excellent catalytic activity toward HER in an acidic electrolyte. The overpotential at the current density of 10 mA cm −2 was only 154 mV in a 0.5 M H 2 SO 4 solution, which was lower than most of the non-precious metal and metal-free catalysts. Density functional theory (DFT) calculation results suggested that the synergistic effect between Fe 3 C nanorods and N dopants could effectively tune the H adsorption energy on carbon resulting in an enhanced HER activity.
Graphical Abstract
研究领域:
材料科学
·
能源化学
·
理论计算
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Pengfei Wan,Xincheng Guo,Shengdong Jing,Shilan Li,Shengjun Lu,Yufei Zhang,Haosen Fan
Lithium-sulfur (Li-S) batteries present tremendous potential in promising high energy storage systems because of their high energy density and specific capacity. However, the shuttle effect and slow reaction kinetics of the intermediate lithium polysulfide (LiPSs) result in fast capacity fading. Herein, multicomponent synergy nitrogen-doped carbon nanotube (CNT) framework dotted by CoFe/FeN 0.0324 /TiN heterostructure (CoFe/FeN 0.0324 /TiN@N-CNT) were developed and prepared by in-situ nitridation approach as polysulfide mediator to simultaneously realize physicochemical adsorption and catalytic conversion of polysulfide. Transition metal nitrides, such as FeN 0.0324 , are known for their polar surfaces that can chemically adsorb polysulfides efficiently. Additionally, CoFe and TiN have been shown to catalyze polysulfide redox reactions. This understanding paves the way for the development of heterostructured CoFe/FeN 0.0324 /TiN nanoparticles that significantly enhance the immobilization, diffusion, and transformation of polysulfides. Moreover, nitrogen-doped carbon nanotubes (CNTs) decorated with bimetallic CoFe afford intriguing benefits. The CoFe alloy not only facilitates the in-situ growth of CNTs but also contributes to prominent Li + /electron conductivity. Together, CoFe and CNTs provide substantial physical confinement and catalytic sites, thereby accelerating redox kinetics and effectively mitigating the shuttle effect. Owing to these advantages, CoFe/FeN 0.0324 /TiN@N-CNT separators exhibit remarkable electrochemical properties including superior rate capacity of 738 mAh g −1 at 3C, high reversible capacity of 708 mAh g −1 at 0.5C after 400 cycles and 607 mAh g −1 at 1C after 1000 cycles with per cycle declining rate of 0.09 % and 0.048 %, respectively, and ultralong cycle life at 4C after 1000 cycle. Even with a relatively high sulfur loading of 2.3 mg, the modified batteries still exhibit a satisfactory reversible capacity at 0.5C. This work paves a unique avenue combined prudent spacial framework with heterogeneous synergy strategy for manufacturing high-energy–density Li-S batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Small Methods
·
2019
·Vol. 4
·期 2
·1900753
·
IF 0
Jipeng Liu,Liwei Dong,Dongjiang Chen,Yupei Han,Yifang Liang,Mengqiu Yang,Jiecai Han,Chunhui Yang,Weidong He
Metal oxides are arguably a promising solution to next-generation high-energy-density anode materials. In particular, molybdenum oxides own high theoretical specific capacity (1117 and 838 mA h g −1 for MoO 3 and MoO 2 , respectively), high chemical stability, and low cost. The low electronic conductivity of MoO 3 limits their charge–discharge rate performances and delithiation capability. By controlling the valence state of MoO x with carbon, partial MoO 3 can be reduced to MoO 2 with low electrical resistance and high-rate capacity. Nonetheless, both molybdenum oxides undergo large-volume expansion/shrinkage and even pulverization in the lithiation/delithiation process. Herein, through a facile pyrolysis method a MoO x /N-doped carbon nanotube (NCNT) anode with controllable valence states of Mo is designed. The high conductivity and flexibility of the NCNT matrix form a stable MoO 2 /MoO 3 anode with finely matched lattices and coordinated 3d electrons. Owing to molecularly close contact between electron-rich CNTs and MoO x , MoO x /NCNTs own a high conductivity of 0.36 S cm −1 , and mitigate the volume expansion in charges and discharges. The MoO 3 /MoO 2 /NCNTs anode delivers an unparalleled high gravimetric capacity of 970 mA h g −1 , over 100-cycle stability and high rate capability.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
Journal of Energy Storage
·
2022
·
IF 8.907
Kailin Li,Hao Teng,Qing Sun,Yongfei Li,Xiaoxue Wu,Xingjian Dai,Yi Wang,Simeng Wang,Yifan Zhang,Kexin Yao,Zhihao Bao,Jinsong Rao,Yuxin Zhang
At present, both easy agglomeration of carbon nanotubes themselves and waste caused by chemical vapor deposition (CVD) have great pollution, which limits the use of carbon nanotubes (CNTs). A large number of hollow polyhedrons containing N-doped carbon nanotubes and Co 3 O 4 nanoparticles (Co 3 O 4 NPs) were well fabricated on a biotemplate by hydrothermal method , stirring method and pyrolysis process . The regular polyhedron was uniformly arranged on the external surface of diatomite with a natural porous structure , which aims to avoid the agglomeration of CNTs. The electrochemical testing result shows that the composite has promising electrochemical performance, which is embodied in a high specific capacity 894.6 F/g at 2 A/g, good rate performance and high cycling property. Finally, an assembled Co 3 O 4 NP@CNTs@Diatomite//GR asymmetric supercapacitor has maximal energy density of 36.8 Wh/kg and maximal power density of 16,326.6 W/kg. Indeed, electrode design in this work provides an environmental synthesis idea for the decoration of CNTs on a certain substrate and displays an original electrode material based on diatomite.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2023
·
IF 4.8
Zanling Huang,Shuqi Zhu,Abebe Reda Woldu,Wenhua Gao,Jing-Xin Jian,Paul K. Chu,Qing-Xiao Tong,Liangsheng Hu
Electrochemical glucose detection co-catalyzed by bimetallic ions is carried out by introducing Co(II) and Cu(II) into the alkaline solution. The technique avoids the complicated electrode design and catalyst poisoning. By using nitrogen-doped carbon nanotubes (NCNT) loaded on carbon cloth (CC) as the working electrode, the bimetal co-catalytic system achieves a sensitivity of 6,909 mA M −1 cm −2 , a detection limit of 0.4 μM (S/N = 3), as well as good selectivity and stability. By performing systematic electrochemical and structural analysis, the mechanism of Co(II) and Cu(II) co-catalysis for glucose detection in the solution is elucidated. Co(II) supplies the dynamic reaction sites and source of active intermediate (CoOOH), while Cu(II) promotes the formation of CoOOH. The results provide mechanistic insights into bimetal co-catalysis of glucose detection and other electrochemical reactions .
研究领域:
电化学
·
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）