JOURNAL OF MATERIALS SCIENCE
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2024
·Vol. 59
·期 38
·18090-18104
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IF 3.5
Gong Xin,Luo Pan,Wang Kaiming,Yang Yang,Zhu Huacheng,Yan Liping,Zhou Yanping
Vanadium nitride (VN) has gained much attention for microwave absorption due to its high electrical conductivity and easily tunable microscopic morphologies. However, its microwave dissipation ability is yet to be enhanced. In this work, vanadium nitride with 3D/2D hierarchical microflower structure is successfully fabricated via a rapid microwave hydrothermal method followed by a nitridation process enabled by the in-situ upstream thermal decomposition of melamine. By incorporating with N-doped graphene (N-rGO) in different ratios, the proportion of conduction loss and relaxation polarization loss in VN/N-rGO could be tuned, yielding a minimum reflection loss of − 45.9 dB at 10.4 GHz with 5 wt% filler loading. Further, to achieve optimal ultra-broadband microwave absorption, a rational double-layer absorber is constructed by attaching the N-rGO layer with lower normalized impedance but high dissipation capability under the VN/N-rGO layer with excessively high normalized impedance, delivering a maximum effective absorption bandwidth of 10.3 GHz at a total thickness of 4.9 mm. Impedance matching and power loss density distribution analysis are done to illustrate the working mechanism of the double-layer structure. Graphical abstract
研究领域:
材料科学
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电磁学
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产品关联
DOI
高影响因子
ACTA MATERIALIA
·
2024
·
IF 8.3
Tianqi He,Xiaoya Kang,Lu Wang,Yunlong Yang,Qianghong Wu,Yuanyou Peng,Fen Ran
In recent years, heterojunction has attracted widespread attention as an anode for sodium-ion batteries since they can effectively optimize the materials’ rate performance and cycling stability. However, the advantage is choked by multi-element composition and stepwise synthesis process. Herein, cobalt sulfide (Co 9 S 8 /CoS) homologous heterojunction deposited at vanadium nitride/carbon nanofibers is synthesized as an excellent anode for high-performance sodium-ion batteries in one step by employing the “3 d -orbital electron complementary effect” combined with high-temperature heat-treatment technology. The Co 9 S 8 /CoS homologous heterojunction successfully overcomes the inherent drawback of Co 9 S 8 and possesses an ultrafast charging/discharging process, outstanding reversible specific capacity, and remarkable rate capability. A systematic study reveals that vanadium nitride is a key trigger for forming Co 9 S 8 /CoS heterojunction. When used as anode materials for sodium-ion batteries, it reaches a high specific capacity of 353.0 mAh/g at a current density of 10 A/g (615.8 mAh/g at a current density of 0.05 A/g) due to the presence of heterointerface. Theoretical calculations show that the construction of the heterostructure enhances the sodium-ion storage capacity and storage kinetics compared with pristine Co 9 S 8 . This discovery opens an interesting strategy for constructing homogeneous heterojunctions and broadens the horizons for designing energy storage and conversion materials.
研究领域:
材料科学
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能源存储与转换
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
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2019
·Vol. 7
·期 10
·5513-5521
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IF 10.733
Peng Zhou,Danning Xing,Yuanyuan Liu,Zeyan Wang,Peng Wang,Zhaoke Zheng,Xiaoyan Qin,Xiaoyang Zhang,Ying Dai,Baibiao Huang
Trinickel nitride as a kind of promising hydrogen evolution reaction (HER) electrocatalyst has attracted much attention in recent years due to its high electrical conductivity and low cost. Herein, we designed and synthesized a novel and efficient Ni3N@VN–NF composite by nitriding treatment of a NiV-LDH precursor. The obtained electrode exhibits superior performances including a much lower overpotential of 56 mV at 10 mA cm−2 and Tafel value of 47 mV dec−1 compared to pure Ni3N–NF and VN–NF electrodes. The Ni3N@VN–NF composite as a cathode and a conventional OER electrode NiFe-LDH–NF as an anode were combined to form a complete water-splitting system. The voltage at 10 mA cm−2 is about 1.55 V, which is superior to the voltage value reported in many literature studies. In addition, the two-electrode system exhibits excellent durability after as long as 50 hours of operation.
研究领域:
材料科学
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电化学
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能源转换与存储
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
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2023
·
IF 5.2
Fupeng He,Jianbo Zhao,Qingqing Hu,Yongjie Liu,Qingyun Huang,Zhixiong You,Xuewei Lv
We investigate the isothermal kinetics of the reduction and nitridation of V 2 O 3 using NH 3 . The reaction mechanism is also discussed based on the thermodynamic and experimental results. The reaction procedure between V 2 O 3 and NH 3 can be divided into two stages. The first stage is mainly the deoxygenation process, whereas the second is the nitridation process. The deoxygenation process follows a two-dimensional phase boundary reaction model, and a modified integrated model (IM + diffusion) was proved to be the best function at temperatures above 1023 K. For the second stage, the three-dimensional diffusion model is determined as the mechanism function. Thermodynamic analysis predicts the feasibility between V 2 O 3 and NH 3 to form VN . The VN product is a solid solution (VN x O y ) (0 < x,y < 1, x + y = 1), which can be formed at 873 K. The Rietveld refinement analysis indicates the N content of VN x O y gradually increases with increasing temperature. The highest N content is approximately 15.83% at 1073 K for 2 h.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Energy Materials
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2019
·
IF 0
Kai Meng,Shuxian Wen,Lujing Liu,Zhijun Jia,Yi Wang,Zhigang Shao,Tao Qi
Layered MoS2 has attracted increasing interests as a promising low-cost alternative to Pt-based electrocatalysts for the hydrogen evolution reaction (HER). As is known to all, insufficient active sites and poor conductivity of MoS2 impede the improvement of its catalytic efficiency. In this work, the vanadium nitride (VN) with an enlarged specific surface area (VN(CTAB), CTAB refers to hexadecyltrimethylammonium bromide) was prepared as a substrate, and MoS2 nanoplates were vertically grown on the obtained VN(CTAB) for the first time. The synthesized MoS2–VN(CTAB) as an electrocatalyst for HER performs a low onset overpotential (85 mV) and small Tafel slope (53.31 mV dec–1) as well as superior stability. Besides the benefits from higher conductivity (106 S m–1) and greater stability of VN(CTAB) beyond the traditional carbon-based substrates, the expanded interlayer spacing (1.00 nm) and extra defects along with the lower valence states of Mo and S due to the stronger electron interaction between VN(CTAB) and MoS2 also effectively contribute to the excellent catalytic performance of MoS2–VN(CTAB). This study shows a new method to design efficient and stable HER electrocatalysts by means of non-carbon substrates.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
Journal of Cleaner Production
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2025
·
IF 10
Ziheng Han,Xiude Hu,Qiuyan Xue,Tuo Guo,Jingjing Ma,Qingjie Guo
The current challenge in the advancement of chemical looping ammonia synthesis (CLAS) technology lies in the poor reaction efficiency of binary transition metal nitrogen carriers (NC), which are limited to a single type. A new type of VN NC modified through the doping with transition metals (Ni, Fe, Co) has been investigated. The loading of Ni, Co and Fe significantly enhances the capability of VN to catalyze the dissociation of H 2 and increased the quantity of surface nitrogen vacancies (Nv), thereby promoting the transformation of nitrogen lattice to produce NH 3 . Theoretical calculation indicated that the presence of Ni is also indicative of its role in promoting the decomposition of H 2 and improving the affinity of lattice nitrogen for H*. The addition of 25 wt% Ni as a dopant has a pronounced activation effect on the VN. This results in a substantial increase in the lattice nitrogen conversion rate from 3.3% to 49.2%. The rate of ammonia production escalated from 30.5 μmol g −1 ·h −1 to 508 μmol g −1 ·h −1 . The Ni-VN demonstrates a sustained selectivity of 87% towards NH 3 at 850 °C. After conducting 8 cycles of experiments, it was observed that the activity of Ni-VN did not exhibit a significant decrease. This study offers a novel viewpoint on the advancement and formulation of transition metal-based NC, which contributes to the progress of low-carbon, environmentally friendly synthetic ammonia technology.
研究领域:
化学工程
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材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2021
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IF 9.127
Siyu Chen,Jinyang Ma,Changsheng Song,Xianshu Cai,Feng Jiao,Hongbin Du
Vanadium nitride (VN) is a promising energy storage material due to its high theoretical capacity and good electrical conductivity . However, the unbearable volume expansion due to the lithium insertion impedes its application for lithium-ion batteries (LIBs). Herein, a simple, template-free strategy is developed to synthesize a micron-sized flower-like hierarchical structure made of N-doped carbon layers , embedding VN nanoparticles and outer carbon shell (denoted as VN/NC-MF@C). Profiting from the unique structure, the VN/NC-MF@C composite delivers an excellent reversible capacity (601 mA h g −1 at 0.1 A g −1 ) and ultra-long cycle durability with retention of 92.6% after 5000 cycles at 2 A g −1 . More remarkably, the LiCoO 2 || VN/NC-MF@C full LIBs also demonstrate extraordinary long-term cycle stability, retaining 94.8% of the initial capacity after 1300 cycles at 1 A g −1 . The excellent electrochemical performance of the composite provides inspirations and strategies for developing new unique hierarchical materials with stable, high-performance properties for commercial use in LIBs.
研究领域:
材料科学
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能源存储与转换
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Liang Liu,Xiaoshuang Zhou,Wei Wang,Kewei Zhang,Xiankai Li,Long Chen,Yanhui Li
Cubic vanadium nitride (VN) holds substantial promise as an anode material for supercapacitors, owing to its high conductivity, theoretical capacity, and a wide negative voltage window. However, the tendency of VN to agglomerate, coupled with poor cycling stability from irreversible volume expansion during charge-discharge cycles, hinders its application in asymmetric supercapacitors. In this work, we reported a one-pot molten salt pyrolysis method to prepare VN/nitrogen doped porous carbon (VN/NPC) materials. The nitrogen-doped carbon material with 3D hierarchical porous structure not only facilitates ion diffusion and charge transport, but also serve as a matrix to in-situ synthesis VN nanoparticles to improve the cycling performance. The VN/NPC exhibits a specific capacitance of 272.3 F/g at 2 mV/s, and 268 F/g at 0.5 A/g. In addition, the VN/NPC demonstrates an excellent cycling stability with only 7 % capacity decay after 10,000 cycles. Furthermore, the all-solid-state asymmetric supercapacitors (ASCs) constructed using VN/NPC as anode and NiCo-layered double hydroxides (NiCo-LDH) as cathode deliver remarkable energy densities of 61.1 and 22.9 Wh/kg at power densities of 700.4 and 7496.6 W/kg, respectively. In addition, this ASCs exhibits excellent cycling stability with 83 % capacity retention after 10,000 cycles. This work provides a green and facile method to prepare anode materials with high capacitance and excellent cycle performance for high energy density ASCs devices.
研究领域:
材料科学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Hailun Yang,Pengge Ning,Hongbin Cao,Menglei Yuan,Jianpeng Feng,Jiaxin Yue,Zhenchao Liu,Gaojie Xu,Yuping Li
Hierarchically nanostructured carbon hybrids with highly exposed active sites and specific surface area have been widely researched in high-performed electrochemical capacitors. Inspired from the synergistic effect of uniformly distributed active components and stable carbon substrate, combining with green solvent extraction process, we explored a facile strategy to prepare vanadium nitride quantum dots/nitrogen-doped hierarchical carbon nanocomposites (VNQD/NDHCs) from vanadium aqueous solution, which can provide large pseudocapacitance and excellent electrochemical stability. Vanadate is selective recovered from aqueous solution in form of vanadium-organic compounds (VAORCs) as precursor. Primary amines favor not only the selective metal-polymer coordination, but also the formation of cross-linked carbon matrix. Then, during chemical molecules vapor deposition (CMVD), the vanadate is in-situ nitrided along with the formation of hierarchical carbon. The prepared VNQD/NDHCs-800 exhibits exceptional capacitance (318.3 F g −1 at 1 A g −1 ) and retains 89.7% of the initial capacities after 12000 cycles. SEM and TEM images confirm that a large amount of quantum dots are well embedded in a graphitic carbon matrix, which provides abundant electroactive sites and fast ion diffusion for capacitive storage. This work indicates that it is feasible to directly recovery valuable metals from aqueous solutions to prepare high-performance electrode materials .
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
·
IF 6.371
Rui Jia Liu,Ling Xu Yang,Wen Jun Wang,Hui Jun Liu,Chao Liu Zeng
capacities Nanosized vanadium nitride (VN) wrapped onto carbon fibers was synthesized by a molten salt disproportionation synthesis method at 800–1,000 ºC, using V and melamine as raw materials in molten (Li,K)Cl salts. Molten salts could accelerate the formation of nanosized VN at a lower temperature, which is possibly associated with the disproportionation reaction of V-ions on g-C 3 N 4 surface. VN displays remarkable application prospects as an anode material for lithium-ion batteries (LIBs), delivering a reversible discharge capacity of 320.1 mAh·g −1 at 1.0 A·g −1 after 500 cycles and 669.4 mAh·g −1 at 0.1 A·g −1 after 230 cycles without capacity attenuation. Such a remarkable cyclability of VN is attributed to the increased surface area and superior structural stability, induced by the dispersion of VN nanoparticles onto high-conductive carbon fibrous network. Li-ions storage mechanism of VN is pseudocapacitive, accompanied with the conversion-type electrochemcial reaction of VN with Li-ions during the de-/lithiation process.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2015
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IF 2.999
Jingxin Zhao,Bao Liu,Shan Xu,Juan Yang,Yun Lu
Porous vanadium nitride (VN) hollow fibers are successfully synthesized using low-cost starting materials by electrospinning combined with subsequent annealing. In this approach, precursor composite fibers are initially synthesized in an electrospinning precursor solution and then calcined at high temperature levels and an appropriate heating rate to form V 2 O 5 hollow fibers. In the subsequent annealing under NH 3 atmosphere, V 2 O 5 hollow fibers act as a template for VN hollow fibers. The as-made VN hollow fibers retain their 1D texture, and their side walls consist of numerous porous nanoparticles . The electrochemical performance of VN hollow nanofibers is investigated, and the specific capacitance is 115 F/g at a current density of 1 A/g in 2 M KOH electrolyte. Meanwhile VN hollow fibers display typical pseudocapacitance properties. The capacitance fade of VN hollow nanofibers during cycling is also studied.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED POWDER TECHNOLOGY
·
2022
·
IF 4.969
Yongjie Liu,Fupeng He,Qingqing Hu,Qingyun Huang,Xuyang Liu,Zhixiong You,Guibao Qiu,Xuewei Lv
Vanadium nitride (VN) has a wide range of application because of its excellent properties, which include high hardness, outstanding wear resistance, and good electrical conductivity. This study investigated the mechanism for the reduction and nitridation of V 2 O 3 with clean ammonia gas, using both experimental and density functional theory (DFT) studies. The experimental results indicated that V 2 O 3 could easily be converted to VN in an ammonia atmosphere at 500–800 °C. The reaction pathway to form VN was V 2 O 3 → VN x O 1– x → VN. Increasing the reaction temperature was conducive to an increase in the N content of VN x O 1– x . A DFT study systematically revealed the adsorption of NH x and H on the V 2 O 3 (0001) surface. The results showed that with the dissociation of NH 3 , its adsorption energy on the surface of vanadium oxide became higher. The whole reaction process could be divided into NH 3 decomposition on the surface and the formation of H 2 O(g). Both of these were endothermic reactions, and the reaction step of generating H 2 O(g) needed a higher temperature. The bonding of V 3c –N facilitated the desorption of O 3c atoms to form H 2 O(g), which explained why VN can be prepared by the reaction of NH 3 and V 2 O 3 .
研究领域:
材料科学
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化学工程
·
理论化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）