Journal of Magnesium and Alloys
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2022
·
IF 11.813
Zhiqiang Lan,Huiren Liang,Xiaobin Wen,Jiayang Hu,Hua Ning,Liang Zeng,Haizhen Liu,Jun Tan,Jürgen Eckert,Jin Guo
Hydrogen is considered one of the most ideal future energy carriers. The safe storage and convenient transportation of hydrogen are key factors for the utilization of hydrogen energy. In the current investigation, two-dimensional vanadium carbide (VC) was prepared by an etching method using V 4 AlC 3 as a precursor and then employed to enhance the hydrogen storage properties of MgH 2 . The studied results indicate that VC-doped MgH 2 can absorb hydrogen at room temperature and release hydrogen at 170 °C. Moreover, it absorbs 5.0 wt.% of H 2 within 9.8 min at 100 °C and desorbs 5.0 wt.% of H 2 within 3.2 min at 300 °C. The dehydrogenation apparent activation energy of VC-doped MgH 2 is 89.3 ± 2.8 kJ/mol, which is far lower than that of additive-free MgH 2 (138.5 ± 2.4 kJ/mol), respectively. Ab-initio simulations showed that VC can stretch Mg-H bonds and make the Mg-H bonds easier to break, which is responsible for the decrease of dehydrogenation temperature and conducive to accelerating the diffusion rate of hydrogen atoms, thus, the hydrogen storage properties of MgH 2 are remarkable improved through addition of VC.
研究领域:
材料科学
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能源化学
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纳米技术
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催化化学
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计算材料学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2021
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IF 6.901
Chang Xu,Xuan Zhao,Mengyao Sun,Jingyuan Ma,Mingxing Wu
In the present study, two typical 2D layered MXenes, i.e., Titanium carbide (Ti 3 C 2 ) and Vanadium carbide (V 2 C) are synthesized via a simple etching method under lower temperature as counter electrode catalysts to achieve the iodide redox couple regeneration in dye-sensitized solar cells. As indicated from the result, Ti 3 C 2 significantly outperforms V 2 C, and the device by exploiting Ti 3 C 2 counter electrode achieves power conversion efficiency (PCE) of 5.3%, while the device by applying V 2 C counter electrode only exhibits a poor PCE of 4.0%. To improve the catalytic activity of the prepared Ti 3 C 2 , the effect of etching time on the catalytic activity has been evaluated, which demonstrates that Ti 3 C 2 etched 24 h exhibits the highest catalytic activity, and the device generates a PCE of 6.2%. Lastly, the catalytic activity of the Ti 3 C 2 is further improved by postprocessing with KOH aqueous solutions, and the PCE value is up-regulated to 7.1%. The high catalytic behavior of Ti 3 C 2 could be attributed to the prominent charge transfer and mass transport properties caused by the specific 2D layer structure, suggesting a potential candidate to the noble metal electrodes.
研究领域:
材料科学
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能源科学
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化学工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
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IF 6.707
Mengmeng Shao,Haodeng Chen,Shiji Hao,Haikun Liu,Yongyong Cao,Yanfei Zhao,Jutao Jin,Haifeng Dang,Yue Meng,Yanping Huo,Lifeng Cui
Cocatalyst loading is an efficient strategy to accelerate the hydrogen evolution reaction, which is the final crucial process to complete photocatalytic hydrogen production and realize solar-to-hydrogen conversion. Herein, we report that N-doped vanadium carbide (NVC) is combined with Pt to form a multifunctional cocatalyst capable of enhancing carrier separation, activating H 2 O, and accelerating H 2 evolution. Our designed Pt/NVC/C 3 N 4 displays much higher photocatalytic activity than g-C 3 N 4 loaded with Pt or NVC. The photocatalytic H 2 evolution rate of Pt/NVC/C 3 N 4 reaches 40 μmol/h, which is three times and one hundred times higher than that of Pt/C 3 N 4 and NVC/C 3 N 4 , respectively. The significantly enhanced photocatalytic activity of Pt/NVC/C 3 N 4 is attributed to the partial synergy between Pt and NVC, where NVC promotes carrier separation and activates H 2 O, and Pt is responsible for boosting proton reduction. Our work demonstrates that hybrid cocatalysts exhibit superior performance compared to traditional single-component cocatalysts, providing guidance for exploring highly active cocatalysts for photocatalysis.
研究领域:
材料科学
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化学
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能源科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Xin Qi,Feifei Nie,Yingshan Wu,Bei Ruan,Kezhong Wu,Mingxing Wu
Vanadium-based carbides have been applied as Pt-free counter electrodes (CEs) electro-catalysts for dye-sensitized solar cells (DSSCs) due to the advantages of earth-abundant reserves, diverse composition , ease modification, and low cost. Herein, the polyoxovanadate (NH 4 ) 2 V 6 O 16 as V source assisted by dicyandiamide (C 2 H 4 N 4 ) as C source via simply physical mixing by ball-milling to assemble VC@C precursors. And then, five different VC@C composites derived from precursors with mass ratios of dicyandiamide to polyoxovanadate of 5:1, 10:1, 15:1, 20:1 and 25:1 at 900 °C, and further achieved power conversion efficiencies (PCEs) of 5.4%, 5.6%, 6.6%, 6.2% and 5.1% as CEs for regenerate traditional I 3 − /I − couple in the encapsulated DSSCs, respectively. The effects of different mass ratio of dicyandiamide on the catalytic performances of VC@C composite CEs were also assessed using cyclic voltammetry , electrochemical impedance spectroscopy and Tafel polarization experiments. The photocurrent-photovoltage ( J - V ) results indicated that VC@C composites CEs had high conductivity and rich number of active sites, which indicated that VC@C composites could be a cost-effective and high-performance alternative Pt-based CEs catalyst for DSSCs.
研究领域:
材料科学
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可再生能源
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2025
·
IF 6.5
Yuhao Yang,Jie Ran,Teng Wang,Yongning Ma,Junli Zhu,Xiaolong Li,Zhuoya Zhao
Aqueous phase reforming of methanol (APRM) is an effective method for the storage and transportation of hydrogen (H 2 ). However, this approach faces challenges due to the limited activity and stability of metal-supported catalysts. In this study, Pt/V 2 O 3 -V 8 C 7 metal-supported catalysts were prepared for APRM and the H 2 production of Pt/V 2 O 3 -V 8 C 7 at 200 °C was 96.52 mmol·g −1 ·h −1 , which is 1.83 times and 1.71 times higher than the H 2 production performance of Pt/V 2 O 3 and Pt/V 8 C 7 , respectively. Moreover, the catalyst demonstrated remarkable stability after 10 in situ cycling tests. Structural characterization revealed that there is a strong metal-support interaction (SMSI) between Pt and V 8 C 7 , and a weak metal-support interaction (WMSI) between Pt and V 2 O 3 , which inhibits the sintering of Pt on the metal-supported catalyst. Furthermore, a straightforward experimental method has been developed that enables accurate inference of the catalytic reaction mechanism in APRM without the need for in situ material characterization. The reaction mechanism indicates that the Pt-V 8 C 7 interface serves as the active site for the methanol decomposition step, while the surface of V 2 O 3 acts as the active site for the water-gas shift reaction step. This strategy of strong-weak MSI offers a novel approach to enhancing both the stability and H 2 production performance in APRM.
研究领域:
催化
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能量转换
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材料科学
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化学反应工程
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-12
·
IF 15.7
Tian Momang,Meng Ke-Juan,Xiong Kunyu,Hussain Iftikhar,Ma Xinwen,Zhang Kaili
Nanothermite has gained significant attention for its exceptional energy release rate and reactivity, making it a promising material for energetic applications. However, nanoparticle agglomeration significantly hinders its energy release efficiency. To overcome this challenge, we developed an innovative bottom-up strategy and a straightforward preparation method to construct a hierarchical Al/CuO/V 2 C nanocomposite. This is achieved through the ordered self-assembly of Al and CuO nanoparticles in an ethanol suspension, using V 2 C MXene as a template. Our findings show that the Al/CuO/V 2 C nanocomposite exhibits distinct morphologies based on V 2 C concentration: nanosheets at lower concentrations and microspheres at higher concentrations. CuO and Al nanoparticles form the first and second layers outside the V 2 C, respectively, due to the interplay between electrostatic forces and covalent Cu-O-V bonds. This unique structure, along with high reactivity of V 2 C, enables complete Al oxidation, achieving a heat release of 3156.2 J g -1 with a 10 wt% V 2 C addition—seven times greater than the Al/CuO control group. The concentration-dependent structure allows for tunable energetic performance, from a rapid 3-ms deflagration to a prolonged 16-ms combustion. Reduced gas release enhances safety, paving the way for applications in microinitiators and advancing nanothermite technology.
研究领域:
纳米材料
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高能材料
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自组装
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燃烧技术
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微型点火器
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science Advances
·
2024
·Vol. 10
·期 15
·
IF 11.7
Hanwen Guo,Xiaoying Chu,Yishun Guo,Jianhua Yang,Yingying Jin,Liyang Zhou,Yaou Peng,Qingying Wang,Fan Lu,Bailiang Wang
Contact lenses (CLs) are prone to adhesion and invasion by pollutants and pathogenic bacteria, leading to infection and inflammatory diseases. However, the functionalization of CL (biological functions such as anti-fouling, antibacterial, and anti-inflammatory) and maintaining its transparency still face great challenges. In this work, as a member of the MXenes family, vanadium carbide (V2C) is modified onto CL via a water transfer printing method after the formation of a tightly arranged uniform film at the water surface under the action of the Marangoni effect. The coating interface is stable owing to the electrostatic forces. The V2C-modified CL (V2C@CL) maintains optical clarity while providing good biocompatibility, strong antioxidant properties, and anti-inflammatory activities. In vitro antibacterial experiments indicate that V2C@CL shows excellent performance in bacterial anti-adhesion, sterilization, and anti-biofilm formation. Last, V2C@CL displays notable advantages of bacteria elimination and inflammation removal in infectious keratitis treatment.
研究领域:
材料科学
·
生物医学工程
·
眼科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）