INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2021
·
IF 3.871
Hairui Xing,Ping Hu,Jiayu Han,Shilei Li,Songwei Ge,Xingjiang Hua,Boliang Hu,Fan Yang,Kuaishe Wang,Pengfa Feng
Molybdenum metal have high brittleness and ductile-to-brittle transition temperature (DBTT) due to the existence of interstitial oxygen impurities, so it is of great scientific significance to strictly control and accurately analyze the oxygen content. In this work, the effects of oxygen on microstructure and evolution mechanism of body-centred-cubic metallic molybdenum are studied. The X-Ray diffraction (XRD), oxygen nitrogen analyzer, scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and electron probe micro-analyzer (EPMA) are used to analyze the chemical composition, microstructure, oxygen existence and distribution form. The results demonstrate that Mo O specimens with up to 3300 ppm of oxygen content have single-phase body-centered cubic microstructure with no precipitates. When the oxygen content in molybdenum increases from 44 ppm to 2200– 3300 ppm, more oxygen exists in the pores between molybdenum grains, and the fracture mode changes from intergranular fracture to intergranular and transgranular mixed fracture. The microhardness increases with increase of oxygen content. These results provide new ideas for controlling the change trend of oxygen in molybdenum and regulating the properties of molybdenum.
研究领域:
材料科学
·
金属学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Ying-jie Sun,Xue-ting Liu,Xin-jie Zhao,Xiao-jing Wang,Jun Zhao,Yu-pei Li,Hui-ying Mu,Fa-tang Li
The tuning of the Mott–Schottky barrier for obtaining superior separation and transfer efficiency of photogenerated carriers is significant for metallic co-catalyst-modified photocatalytic materials. Metallic cobalt phosphide (CoP) has been regarded as a promising co-catalyst for replacing Pt in the photocatalytic hydrogen evolution reaction (HER). However, it is still challenging to enhance the kinetics of CoP for the HER while lowering the Schottky barrier and improving electron transport properties. Herein, Mo metal was introduced into CoP and graphite carbon nitride (g-C3N4) as a bridge of electron transfer channels for synchronous tuning of the Schottky barrier. The analyses showed that the original Schottky contact between CoP and g-C3N4 was transformed into an ohmic contact by the introduction of metallic Mo, which caused a decrease in the Schottky barrier and even improved the charge transfer, lowered the HER potential, and accelerated the HER kinetics process of CoP. After rational assembly, the optimum photocatalyst (Mo-CoP@CN-1.0) showed a remarkable photocatalytic HER rate of 1.47 mmol g−1 h−1 under visible light irradiation, which was about twice as high as that of the optimal Pt modified g-C3N4. This study provides a new prospect for the rational design of a high-efficiency co-catalyst and provides a new way for regulating the Mott–Schottky barrier.
研究领域:
材料科学
·
光催化
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2016
·Vol. 4
·期 37
·14204-14212
·
IF 8.262
Bofei Liu,Zhonghua Jin,Lisha Bai,Junhui Liang,Qixing Zhang,Ning Wang,Caichi Liu,Changchun Wei,Ying Zhao,Xiaodan Zhang
We report molybdenum (Mo) metal-supported amorphous molybdenum sulfide (a-MoS3) catalysts with a porous and nanostructure nature, which exhibit excellent catalytic activity for the hydrogen evolution reaction (HER) in wired solar-water-splitting devices. Mo-supported a-MoS3 catalysts were prepared by wet chemically synthesizing a-MoS3 nanoparticles at room-temperature and then loading with Earth-abundant and scalable Mo metals sputtered at low temperature (100 °C). Electrochemical studies and applications in wired photoelectrochemical/photovoltaic (PEC–PV) solar-water-splitting devices reveal that the HER performance of wired PEC–PV solar-water-splitting devices can be efficiently enhanced with the proposed highly conductive Mo-supported a-MoS3 catalysts by enlarging the electrochemically active areas, accelerating the electron transport to active sites, and improving the charge transfer at the catalysts/electrolyte interfaces. The low-temperature preparation of highly active Mo-supported a-MoS3 catalysts paves the way to integrating them into various high-performance PV devices to develop highly efficient, scalable, low-cost, and monolithic PEC–PV solar-water-splitting devices.
研究领域:
材料科学
·
能源科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Nano
·
2023
·
IF 17.1
Sanjiang Pan,Renjie Li,Jin Wang,Qixing Zhang,Manjing Wang,Biao Shi,Pengyang Wang,Ying Zhao,Xiaodan Zhang
Photovoltaic hydrogen production from seawater is of great significance. Challenges of solar-driven seawater electrolysis, for example, competing among chlorine evolution reactions, chloride corrosion, and catalyst poisoning, seriously restrict the development of this technology. In this paper, we report a two-dimensional nanosheet quaternary metal hydroxide catalyst composed of Ni, Fe, Cr, and Mo elements. By in situ electrochemical activation, a partial Mo element was leached and morphologically transformed in the catalyst. The higher metal valence states and many O vacancies were obtained, providing excellent catalytic activity and corrosion resistance in overall alkaline seawater electrolysis operating at an industrial-required current density of 500 mA cm–2 over 1000 h under 1.82 V low voltages at room temperature. The floating solar seawater splitting device shows a 20.61 ± 0.77% efficiency of solar energy to hydrogen (STH). This work demonstrates the development of efficient solar seawater electrolysis devices and potentially promotes research on clean energy conversion.
研究领域:
材料科学
·
可再生能源
·
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）