ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Zhao Liu,Yuxuan Liu,Huawei He,Hongbo Shao,Yi Zhang,Jing Li,Weiwei Cai
Hydrogen production by water splitting has the characteristics of clean, efficient, and strong operability. However, it is limited by the low activity and insufficient stability of cathode and anode catalysts. Therefore, cost-effective catalysts for efficient cathodic hydrogen evolution reaction (HER) and anodic oxygen evolution reaction (OER) have to be developed. In this work, Ru/Mo 2 C heterojunctions are constructed to regulate the valence of Ru and Mo in the catalyst to simultaneously boost HER and OER in acidic conditions. Consequently, the overpotentials providing 10 mA/cm 2 HER and OER in the acidic electrolyte are reduced to 40 mV and 215 mV, respectively. Finally, only 1.51 V applied voltage is required to achieve 10 mA/cm 2 acidic overall water splitting. Taking stability into consideration, the Ru/Mo 2 C catalyst shows good application prospects in practical acid water electrolysis devices.
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
Journal of Materials Chemistry A
·
2025
·
IF 9.5
Xinghang Duan,Qiaolin Li,Tiantian Cao,Shengxiang Xiong,Gang Chen,Chengjun Dong,Hongtao Guan,Zongyou Yin
The development of advanced electromagnetic (EM) wave absorbers is crucial for applications in stealth technology and EM interference shielding. A major challenge in this field is achieving high absorption efficiency across a broad frequency range while maintaining lightweight and structurally robust materials. In this study, we successfully developed a precise and flexible synthesis strategy to prepare hollow C/Co/Mo2C cubes using Zn/Co(C4O4)(H2O)2 as a flexible template, which offers the advantages of simultaneous removal and easy control of metal Co content. The shell of the hollow cubes can be further optimized by changing the oxidizer content for polypyrrole (PPy). At optimum shell thickness and Co content, the C/Co/Mo2C-0.4 composites, featuring hollow but perforated structures, exhibit superior EM wave absorption properties, with a minimum reflection loss (RLmin) of −73.46 dB and an effective absorption bandwidth (EAB) of 5.20 GHz at 2.0 mm with 15 wt% filler. Detailed investigations reveal that the hollow C/Co/Mo2C-0.4 cubes provide polarization loss, conduction loss, magnetic loss, and optimal impedance matching characteristics, significantly enhancing EM wave absorption performance. This work offers a promising strategy for assembling multiple components into a hollow architecture, offering superior molybdenum carbide microwave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
SYNTHETIC METALS
·
2021
·
IF 3.266
Siqin Jia,Qiguan Wang,Jian Chen,Sumin Wang
Carbon doped metallic compounds have attracted a great deal of interest due to their new synergistic properties and enhanced catalytic performance from the doped-element induced defects. In this paper, polyaniline (PANI) is used as the carbon source to dope molybdenum carbide , which is annealed at 1000 °C to be nitrogen-doped carbon coupled with Mo 2 C (NC@Mo 2 C). Through the XRD , SEM and TEM methods the prepared NC@Mo 2 C composite is thoroughly characterized. The NC@Mo 2 C composite illustrates two-dimensional nanoplate morphology, and shows low overpotential in hydrogen evolution reaction (HER, 0.04 V) and oxygen evolution reaction (OER, 0.13 V) in 1 M KOH solution. Tafel slopes of NC@Mo 2 C for HER and OER are 100 mV decade −1 and 99 mV decade −1 , respectively, rather lower than pure Mo 2 C (HER: 130 mV decade −1 and OER: 126 mV decade −1 ). The Raman and XPS results show that it is the structural defects of Mo 2 C derived from NC doping that activate the reaction. Meanwhile, the NC doping and resulted defects enhance the conductivity of Mo 2 C, as well as endow NC@Mo 2 C nanoplates high electrochemical active surface area, facilitating the ion transfer, water absorption and gas desorption. The results of our work open up a new chance to design efficient non-noble metal-based catalysts for water electrolysis.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Rui Jiang,Bowen Deng,Huijun Liu,Wen Lei,Liu Pi,Liangyou Hu,Xuhui Mao,Xinyu Li,Yaxu Wen,Dihua Wang
A facile synthesis process that facilitates the industrial-scale production of catalysts is the prerequisite of the hydrogen evolution reaction (HER) industry. Molybdenum-based catalysts are ideal alternatives for precious-metal-based HER materials; however, they remain challenging in scale-up preparation due to the costly and complex Mo sources. Herein, we propose a molten salt paired electrolysis approach to synthesize transition-metal-doped Mo2C catalysts directly from molybdenite (mainly consisting of micrometer-scale MoS2 bulks), an earth-abundant natural Mo ore. Unlike Fe-doped Mo2C in which those transition metal dopants are inclined to diffuse into inner planes of Mo2C, this unique synthesis approach leverages the differences in transition metal diffusion energy barriers, ultimately leading to the development of Ni-doped Mo2C catalytic materials with specific Ni-enriched interfaces. Owing to the unique design and structures of the catalyst, the interfacially Ni-enriched Ni-doped Mo2C exhibited promising HER performance and long-term stability. Very interestingly, MoS2 nanoflakes, as side products, can be collected at the anode side while interfacially Ni-enriched Mo2C was concurrently obtained at the cathode side during the electrolytic synthesis process. This work not only deepens our knowledge on constructing active-site-enriched interfaces that are beneficial to HER but also gives clues to upcycling raw materials.
研究领域:
材料科学
·
电化学
·
能源催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Mengyao Li,Lixin Wang,Wanning Xiong,Linlin Zhao,Yi Tian,Mengting Cheng,Yuzhu Wang,Zejun Li,Xinjun Wang,Qingquan Sheng,Yongfeng Luo
The rational design and synthesis of carbon nanocages with highly complex porous structures are continuously facing challenges in the development of high-performance supercapacitors (SCs). The electrochemical performance characteristics of electrodes rely on their compositions and fabrication methods. Here, we propose a universal and efficient approach for the in-situ synthesis of zeolitic imidazolate framework-8 (ZIF-8) on porous carbonized wood, where the selective utilization of hexacarbonyl molybdenum protects the structural integrity of the ZIF-8 precursor, preventing collapse during thermal treatment. The subsequent pyrolysis process leads to the formation of small-sized molybdenum carbide (MoC) which are embedded in carbon nanocages (CN). The composite electrode consists of MoC/CN embedded in a porous carbonized wood (PCW), and it shows area-specific capacity of 9.7F cm −2 and 9.4 F cm −2 at 5 mA cm −2 and 30 mA cm −2 , respectively. Subsequently, the symmetric supercapacitor , with two MoC/CN@PCW electrodes exhibits a areal specific capacitance of 2.7 F cm −2 at 5 mA cm −2 . Moreover, this supercapacitor maintains an capacitance retention rate of 98.5 % after 12,000 discharge cycles. The supercapacitor exhibits a power density of 6.5 mW cm −2 , resulting in an energy density of 0.864 mWh cm −2 . Therefore, the utilization of wood-based electrodes holds promise for energy storage systems.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2018
·
IF 4.908
Yaqiu Tao,Lulu Tao,Zhigang Pan,Simin Qiu,Xiaodong Shen
Formic acid is a promising hydrogen storage material for its high H 2 capacity, easy transfer and moderate H 2 regeneration conditions. Active carbon supported Mo 2 C with or without Co doping were used as the heterogeneous catalyst in the decomposition of a high concentrated aqueous solution of formic acid up to 50% on a fixed bed reactor. For a given flow rate and reaction temperature, though higher volume of H 2 is produced per unit time, the increase in formic acid’s concentration reduces both H 2 selectivity and formic acid conversion rate. At 250 °C, a stream of 236 mL/min H 2 was generated continuously at a high H 2 selectivity (91%) and formic acid conversion rate (86%), from a 10% formic acid fed at the flow rate of 5 mL/min. High reaction temperature improved the conversion of formic acid feed at little expense of H 2 selectivity. The doping of Co in the Mo 2 C lattice improves the H 2 selectivity to 100% at 100–200 °C. A life time study showed the stability of this system by the remained high H 2 selectivity in formic acid decomposition. This work of using active carbon supported molybdenum carbides and high concentrated aqueous formic acid, opens up a new route for the portable H 2 generator using formic acid as a hydrogen storage material at no environmental risk.
研究领域:
化学工程
·
能源科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
POLYHEDRON
·
2018
·
IF 2.067
Chunxia Jiang,Yiping Tang,Zhi Zeng,Jinwei Gao,Maosheng Li,Yuhui Zheng
Europium incorporated molybdenum carbide (Mo 2 C) has been assembled at 800 °C based on a single step and the synthesis processes have been discussed. (NH 4 ) 6 Mo 7 O 24 ·4H 2 O has been employed as a precursor and p -phenylenediamine has been selected as the carbon source. In contrast to conventional organic dyes, this novel lanthanide-activated phosphor provides red luminescence in the form of higher monochromatic purity due to the parity forbidden transitions. More importantly, the emission intensity of 5 D 0 → 7 F 2 transition increased depending on the incorporation of europium ions and the most suitable doping concentration will be 0.3 mmol. The utilization of f – f transition of Eu 3+ in molybdenum carbide has made the red emission materials accessible for application in the area of display, electronics and bio-imaging.
研究领域:
材料科学
·
光学
·
生物成像
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2018
·
IF 5.116
Tingting Liu,Heng Liu,Xiuju Wu,Yanli Niu,Bomin Feng,Wei Li,Weihua Hu,Chang Ming Li
Molybdenum (Mo) based materials including its phosphides, carbides, nitrides , oxides, dichalcogenides and metallic alloys have received particular interest in recent years for sustainable hydrogen evolution reaction (HER) electrocatalysis . In this study, a novel Mo 2 C/MoP hybrid nanoparticle embedded N, P co-doped carbon nanofibers on carbon fiber paper (Mo 2 C-MoP NPC/CFP-800) is successfully prepared as a highly efficient hierarchical HER electrocatalyst . Benefitting from its structural advantages and compositional merits, this Mo 2 C-MoP NPC/CFP-800 electrocatalyst displays remarkable catalytic activity as well as excellent durability for HER. Only 85 and 146 mV overpotential is required to drive a HER current density of 10 mA cm −2 in acidic and alkaline solution, respectively. Remarkably, this electrocatalyst is also able to fulfill efficient HER even in seawater . Further, this work reveals that the Mo 2 C/MoP hybrid nanoparticle is superior to MoP nanoparticle under present system in HER electrocatalysis, which may offer valuable clues on further design and synthesis of HER electrocatalysts.
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
Bioresource Technology Reports
·
2020
·
IF 0
Chunyan Yang,Houfang Lu,Yanchun Shi,Yingming Zhu,Kejing Wu,Yingying Liu,Changjun Liu,Bin Liang
In this study, Kraft lignin was efficiently converted into aromatic monomers of arenes, aromatic alcohols, and aromatic aldehydes over nano molybdenum carbides catalysts supported on porous ZSM-22, ZSM-5, USY, Beta, and IM-5 zeolites in ethanol. The results showed that ZSM-22 exhibited the highest performance with maximum aromatic yield of 0.609 g/g Kraft lignin at 280 °C for 3 h with 20% Mo loading, and the catalytic performance over ZSM-22 retained for 4 recycling runs without obvious aromatic yield loss. The high activity over ZSM-22 zeolite is attributed to the high dispersion of β-Mo 2 C particles with more exposed active sites and enhanced accessibility of lignin to β-Mo 2 C in large pores. Aggregation of β-Mo 2 C for higher Mo loading is unfavorable for Kraft lignin decomposition. The performances over differently pretreated ZSM-22 zeolites demonstrate that large pore size and external surface areas are key factors in determining the catalytic activity .
研究领域:
化学工程
·
材料科学
·
能源化学
✓ 已验证
DOI
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2017
·
IF 3.582
Pan Wang,Ji Qi,Xiaozhen Chen,Chuang Li,Tonghua Wang,Changhai Liang
Hydrogen evolution reaction (HER) is considered to be one of the most promising strategies to create hydrogen. Recently, searching high-efficient, stable, and earth-abundant electrocatalysts to replace precious metals for practical utilizations of HER is attracting more and more attentions. Herein, novel molybdenum carbide nanobelts containing Mo of high-valence state derived from MoO 3 -ethylenediamine inorganic/organic hybrid precursors are successfully synthesized via a facile one-pot pyrolysis method. The molybdenum carbide nanobelts are characterized using XRD , SEM, TEM and XPS . Moreover, the high-valence state Mo and their relative content in the molybdenum carbide nanobelts can be identified by XPS. The high-resolution XPS spectra of Mo 3d indicates in the molybdenum carbide nanobelts the proportion of high-valence state Mo in active Mo components is 51.3%. More importantly, the as-synthesized products exhibit excellent electrocatalytic activity for HER with a low onset overpotential of 50 mV and a small Tafel slope of 49.6 mV dec −1 in acidic medium (0.5 M H 2 SO 4 ). Besides, the catalysts require only overpotentials of 143 and 234 mV to achieve current densities of 10 and 220 mA cm −2 , respectively. Furthermore, they also exhibit good durability after 2000 cycles and constant current density test. Such excellent electrocatalytic HER performance can be ascribed to the high intrinsic activity of high-valence state Mo in Molybdenum Carbide. Synthesizing molybdenum carbide with high-valence state Mo electrocatalysts for HER will open up an exciting alternative avenue to acquire outstanding HER electrocatalytic activity.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
·
IF 7.2
Peirong Chen,Hao Zhong,Liuzhang Ouyang,Haiwen Li
Interfacial engineering is an effective approach for regulating the electronic structure of molybdenum carbides and promoting the hydrogen evolution reaction (HER). However, the development of a facile, cost-effective, and scalable synthesis method is crucial for industrial applications. In this work, we developed a mechanochemical method for the preparation of a composite of MoO 2 /MoC with superior HER electrocatalytic performance in alkaline solutions. The MoO 2 /MoC composite can be easily formed by ball milling for 1 h at ambient conditions, and this process can be scaled up for large-scale industrialization. The composite construction leads to a redistribution of electrons around the interface, optimizing the adsorption energy and enhancing the HER performance beyond that of Pt/C catalysts. This strategy provides a new route for the simple and efficient preparation of high-activity electrocatalysts.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2025
·Vol. 15
·期 29
·23819-23826
·
IF 4.6
Yanhong Ding,Zhichao Gao,Rongpeng Lin,Yong Cao,Haoyang Liu,Yulin Zhou,Haifeng Xu,Jiayi Liu,Fangqi Ren,Yirong Zhu
Lithium–oxygen (Li–O2) batteries are considered an important candidate for the next generation of energy storage systems due to their ultra-high theoretical energy density (11 586 mA h g−1), but their slow kinetic reactions, high overpotential and cyclic instability seriously limit their practical applications. In this study, sulfur modified Mo2C (S@Mo2C) cathode materials were prepared by hydrothermal synthesis by sulfur (S) doping to optimize the electronic structure and catalytic activity of Mo2C (Mo2C). Experiments show that S@Mo2C exhibits significantly improved electrochemical performance compared to commercial Mo2C: its specific capacity is up to 3955 mA h g−1 (commercial material only 508 mA h g−1), the charge and discharge overpotential is reduced to 0.26 V (53.6%), and the capacity retention rate remains 77.8% after 250 cycles. X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analysis showed that the introduction of sulfur induced the formation of a heterostructure of MoS2/MoS3 in the Mo2C lattice, which enhanced the conductivity and oxygen reduction/precipitation (ORR/OER) activity of the material. In addition, sulfur doping promotes the formation of highly conductive amorphous Li2O2 and effectively inhibits the accumulation of insulating ring Li2O2, thus significantly improving the cycle stability and energy efficiency of the battery. This study provides a new structural regulation strategy for the design of high efficiency lithium oxygen battery catalysts.
研究领域:
能源存储
·
材料科学
·
电化学
✓ 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）