ACS Applied Materials & Interfaces
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2019
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IF 8.456
Rui Jiang,Liu Pi,Bowen Deng,Liangyou Hu,Xianglin Liu,Jiaxin Cui,Xuhui Mao,Dihua Wang
A binderless composite cathode for efficient electrocatalytic hydrogen evolution reaction (HER), Mo2C-decorated carbon cloth (denoted as CC/MC), is simply fabricated via a novel and unique strategy which involves a solid–solid phase interfacial electrochemical reaction between carbon fiber and bulk-MoS2 in molten NaCl–KCl (700 °C). MoS2, evenly coated on carbon cloth (CC), is electrochemically reduced in situ and readily reacts with the carbon fibers of CC current collector to form a Mo2C nanoparticle layer. The experiment and calculation results show that the applied electric field results in a declining migration barrier of Mo vacancies in Mo2C lattice, which promotes the diffusion of Mo atoms into carbon across the interfacial Mo2C layer, thereby impelling the combination of Mo with C in depth. The electrochemical tests indicate that the optimized cathode (CC/MC-2) exhibits a small overpotential of 134.4 mV at 10 mA cm–2 and stays stable for HER in acidic media. The catalytic capacity for N2 reduction of CC/MC-2 is analyzed. In addition, a Ni-doped Mo2C-modified carbon fabric electrode with enhanced HER activity (η10 = 96.6 mV) can be prepared through a similar process.
研究领域:
材料科学
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电化学
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能源转换与储存
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 38
·20518-20527
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IF 11.9
Wenxuan Hou,Baojun Wang,Shikuo Li,Fangzhi Huang,Hengxiu Yang,Hui Zhang
In the face of increasingly serious electromagnetic radiation pollution, there is an urgent need to develop new materials with efficient electromagnetic wave absorption. Heterointerface engineering can control the electromagnetic characteristics by adjusting the conductivity and complex permittivity to achieve excellent electromagnetic wave absorption ability. Herein, inspired by honeycomb with an ordered porous structure, we designed a N-doped honeycomb-like porous carbon matrix via a spatially confined-etching strategy, and ultra-fine sized Mo2C nanoparticles were embedded to construct multiple heterointerfaces. Simultaneously, the unique 3D structure successfully prevents the agglomeration of nanoparticles, which is conducive to deeply constructing heterointerfaces and thus enhancing interfacial polarization. Furthermore, the doping of heteroatoms can also trigger strong dipole polarization to improve electromagnetic energy conversion efficiency. Consequently, the composite combined honeycomb-like porous structure with rich Mo2C/C heterointerfaces presents outstanding electromagnetic absorption with a minimum reflection loss value of −65 dB and effective absorption bandwidth up to 5.52 GHz. This study provides new strategies and insights for heterointerface engineering to achieve efficient electromagnetic absorption performance and has broad application prospects in the field of electromagnetic wave absorption.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
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2024
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IF 4.3
Zhen Li,Xianhui Wang,Da Li,Hongbo Zhang,Bochen Zhang
The Mo 2 C@CNTs/Cu-20wt.%Mo composite materials with outstanding mechanical properties and electrical conductivity were prepared via the combination of mechanical wet-mixing, ball-milling and spark plasma sintering technology. By regulating the morphology and content of Mo 2 C decorated on CNTs, the Mo 2 C nanoparticles are anchored on CNTs and well bonded with the matrix, resulting the good interfacial bonding in the composite material. The Cu-20wt.%Mo composite material reinforced by 0.2wt.%Mo 2 C@CNTs exhibits a yield strength of 342.19 MPa and an ultimate tensile strength of 390.37 MPa, which are respectively increased by 23.13 % and 20.34 % as compared to the Cu-20wt.%Mo. Besides, the electrical conductivity of the 0.2wt.%Mo 2 C@CNTs/Cu-20wt.%Mo composite material is also improved by 6.89 %. Furthermore, the strengthening effect of Mo 2 C@CNTs/Cu-20wt.%Mo composite material can be attributed to the contribution of Mo 2 C nanoparticles, which not only enhance the CNTs load transfer strengthening but also promote the dislocation strengthening and Orowan strengthening.
研究领域:
材料科学
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纳米技术
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2020
·Vol. 12
·期 23
·6040-6049
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IF 4.853
Yongli Sun,Feifei Peng,Luhong Zhang,Bin Jiang,Haozhen Dou,Na Zhang,Mi Xu,Na Yang
Graphical Electrocatalytic Hydrogen Evolution : The morphology and diameter of porous Mo 2 C can be tuned in an easy and precise way. 0D/3D Mo 2 C P/Mo 2 C F exposes abundant active sites and possesses super water affinity to accelerate electrolyte and gas diffusion, and it works better than commercial Pt/C at high current densities in 1.0 M KOH. Herein, a novel 6∼9 nm nitrogen-doped Mo 2 C nanoparticles (Mo 2 C P) homogeneously decorated on 3D porous nitrogen-doped Mo 2 C microflowers (Mo 2 C F) were prepared in situ to form 0D/3D Mo 2 C P/Mo 2 C F. This special structure combines the advantages of Mo 2 C P and porous Mo 2 C F to provide a high density of reaction sites and facilitate the diffusion of electrolyte and hydrogen. Mo 2 C P/Mo 2 C F exhibits excellent HER performance in both alkaline and acidic solutions. It only requires an overpotential of 96 and 118 mV to achieve a current density of 10 mA cm −2 ( η 10 ) in 1.0 M KOH and 0.5 M H 2 SO 4 , respectively. Moreover, it works better than commercial Pt/C at high current densities in 1.0 M KOH. The Tafel slopes are less than 50 mV/dec in both media, suggesting an obviously fast HER kinetics. Additionally, this study presents a universally applicable method to prepare M x C P/Mo 2 C F (M=Fe, Co, V) for different applications.
研究领域:
材料科学
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电化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2020
·
IF 4.939
Yuanyuan Guo,Qi Huang,Junyang Ding,Li Zhong,Ting-Ting Li,Yue Hu,Jinjie Qian,Shaoming Huang
The exploration and development of cost-effective and highly stable electrocatalysts with the highest possible energy efficiency remain a constant pursuit in the catalyst design and synthesis for electrocatalytic hydrogen evolution reaction (HER). In this work, a convenient approach is proposed to synthesize a type of ultrafine Mo 2 C nanoparticles in average sizes of 3–4 nm embedded in hierarchically porous N-doped carbon material calcined from bimetallic ZnMo-MI (MI = 2-methylimidazole) is obtained at 1000 °C, denoted as ZnMo-MI-1000 . First of all, the crystalline hybrid metal-organic framework of ZnMo-MI is fabricated from zeolitic imidazolate framework of Zn-MI precursors via solvothermal reaction, in which the conversion from Zn-MI to ZnMo-MI occurs gradually over time. After calcination , the as-obtained ZnMo-MI-1000 sample shows a satisfying HER performance with the small overpotential of 83.0 mV in 0.5 M H 2 SO 4 and 100.1 mV in 1.0 M KOH to reach a current density of 10 mA cm −2 , which is attributed to ultrasmall Mo 2 C, Mo and N-doped graphitic carbon matrix. The multiporous network of ZnMo-MI-1000 can provide continuous mass transportation with a minimal diffusion resistance that produce effective electrocatalytic kinetics in both acidic and alkaline media , which is utilized as a highly active and durable nonprecious metal electrocatalyst for HER.
研究领域:
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
Energy Material Advances
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2022
·
IF 0
Jinxing Yu,Xiaoxiang Xu
Halide perovskites have been emerging as promising photocatalytic materials for H 2 evolution from water due to their outstanding photoelectric properties. However, the lack of proper surface reactive sites greatly hinders the photocatalytic potential of these fascinating compounds. Here, Mo 2 C nanoparticles have been anchored onto methylammonium lead iodide (MAPbI 3 ) as a nonnoble metal cocatalyst to promote H 2 evolution reactions. The Mo 2 C nanoparticles have opposite zeta potential with MAPbI 3 thereby electrostatically assembled onto the MAPbI 3 surface, i.e., Mo 2 C@MAPbI 3 . Our results show that the anchored Mo 2 C nanoparticles have a strong interplay with MAPbI 3 substrate so that photogenerated electrons of MAPbI 3 can be rapidly separated and transferred into Mo 2 C for further H 2 evolution reactions. Under optimal conditions, Mo 2 C@MAPbI 3 delivers exceptionally high photocatalytic performance for visible light-driven H 2 evolution that clearly outperforms pristine MAPbI 3 and Pt-deposited MAPbI 3 . An apparent quantum efficiency as high as 12.65% at 600 ± 40 nm has been attained for H 2 evolution, surpassing most of the MAPbI 3 -based photocatalyst reported. These results signify the usefulness and applicability of Mo 2 C as a new nonnoble metal-based cocatalyst in solar water splitting.
研究领域:
材料科学
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光催化
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能源化学
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半导体物理
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纳米催化
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太阳能转化
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水裂解制氢
✓ 已验证
DOI
Science Bulletin
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2018
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IF 4.136
Zhen-Dong Yang,Zhi-Wen Chang,Qi Zhang,Keke Huang,Xin-Bo Zhang
A facile synthesis of the hierarchically porous cathode with Mo 2 C nanoparticles through the electrospinning technique and heat treatment is proposed. The carbonization temperature of the precursors is the key factor for the formation of Mo 2 C nanoparticles on the carbon nanofibers (MCNFs). Compared with the Mo 2 N nanoparticles embedded into N-doped carbon nanofibers film (MNNFs) and N-doped carbon nanofibers film (NFs), the battery with MCNFs cathode is capable of operation with a high-capacity (10,509 mAh g −1 at 100 mA g −1 ), a much reduced discharge-charge voltage gap , and a long-term life (124 cycles at 200 mA g −1 with a specific capacity limit of 500 mAh g −1 ). These excellent performances are derived from the synergy of the following advantageous factors: (1) the hierarchically self-standing and binder-free structure of MCNFs could ensure the high diffusion flux of Li + and O 2 as well as avoid clogging of the discharge product, bulk Li 2 O 2 ; (2) the well dispersed Mo 2 C nanoparticles not only afford rich active sites, but also facilitate the electronic transfer for catalysis.
研究领域:
材料科学
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电化学
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纳米技术
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能源存储
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Shuanghui Zeng,Xiangqun Zeng,Lan Jiang,Zhao Ding,Jiao-Jing Shao,Jie Zhao
s Developing efficient non-noble metal-based electrocatalysts for the hydrogen evolution reaction (HER) is urgently required for the large-scale electrolysis of water. Mo 2 C shows excellent HER catalytic activity. The construction of heterostructures by combining Mo 2 C and carbonaceous materials provides an effective strategy to modulate the electronic structure and hydrogen adsorption ability of molybdenum carbide . The β-Mo 2 C nanoparticles bundled on semiconducting carbon nanotubes (CNTs) with a Mott-Schottky heterojunction has been prepared in situ on the carbon cloth via a facile solvothermal and annealing process. Contributing to the synergistic effect of β-Mo 2 C and CNTs, the synthesized Mo 2 C/CNTs@CC electrode exhibits greatly enhanced HER catalytic activity with an overpotential of 123 mV to achieve a current density of −10 mA cm −2 , a Tafel slope of 51 mV dec −1 , and excellent durability. DFT calculations indicate that the CNTs donate electrons to β-Mo 2 C to enhance the coupling interfaces within β-Mo 2 C and CNTs and modify the electronic structure, resulting in a lower reaction barrier in the Volmer step and faster HER activities. This work provides a synthetic route to Mott-Schottky heterostructure Mo 2 C/CNTs with excellent HER catalytic activity.
研究领域:
材料科学
·
电化学
·
纳米技术
·
催化
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）