Coatings
·
2023
·Vol. 13
·期 7
·1266
·
IF 3.4
Qian Kou,Weiliang Jin,Chuntao Ge,Jie Pang,Jun Zhang,Geir Martin Haarberg,Saijun Xiao,Ping Wang
In this paper, electrodeposition of a molybdenum coating was conducted in Na3AlF6-NaF-Al2O3-MoO3molten salts at 930 °C to investigate the availability of preparation of thick molybdenum coatings. The effects of current density and electrodeposition time on the morphology of the produced molybdenum coating were studied. With the increase of current density (10~70 mA·cm−2), the coating thickness was increased from 10 μm to 30 μm, with all the current efficiency above 97%. Under a current density of 30 mA/cm2, with the rise of electrodeposition time (10~60 min), three stages of the deposit growth were observed, including the formation of a large number of fine crystals, transformation into fibrous morphology and well-developed faceted grains. The formation of a large number of fine crystals at the initial stage of the electrodeposition could facilitate electroplating molybdenum coatings with good quality at higher current density and longer duration. Thus electrodeposition at a current density of 100 mA·cm−2for 3 h has been performed, resulting in the preparation of relatively flat, dense, and coherent molybdenum coatings with a thickness of 140 μm on a nickel substrate, with a current efficiency above 85%. It is anticipated that the electrodeposition of molybdenum coatings in the present molten system is suitable for electroplating thick molybdenum coatings.Keywords:cryolite-based molten salt;electrodeposition;molybdenum coating;nickel substrate
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 Electrochemical Science
·
2023
·
IF 1.5
Huazhen Cao,Zhizhou Yue,Huibin Zhang,Guangya Hou,Yiping Tang,Guoqu Zheng
Electrodeposition of refractory metals is a challenging issue in the electroplating field owing to their low reduction potential. Electrodeposition of molybdenum in MoCl 5 -BMIMPF 6 by a cyclic scanning regime was introduced in this paper. Ni-Mo and Pt/Ni-Mo deposits were prepared by underpotential deposition to induce the bulk deposition of molybdenum. The coatings were observed and characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The electrochemical behavior of metallic molybdenum in ionic liquids was studied by cyclic voltammetry and chronoamperometry. The results show that the initial nucleation/growth process of molybdenum in MoCl 5 -BMIMPF 6 follows three-dimensional progressive nucleation with diffusion-controlled growth, and the nucleation rate of molybdenum is slow in the ionic liquid system. The effects of supporting electrolytes and sputtering Pt/Ni electrodes were particularly studied. A yellow-brown uniform coating with more refined crystalline grains was obtained on the Ni surface by the addition of NaF due to its positive role in the mass transfer process and good complexing actions that promote nucleation. A gray-white coating with metallic luster was successfully fabricated on the surface of sputtered Pt/Ni because the substrate with a high work function is benign to molybdenum growth at a lower temperature and more positive potentials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Applied Nanoscience
·
2021
·Vol. 11
·期 3
·841-847
·
IF 3.674
Yi J.,Yang M. M.,Luo X. D.,Rosenkranz A.,Wang B.,Song H.,Jiang N.
This study aims at assessing the tribological performance of novel self-lubricating chemical vapor-deposited MoS 2 coatings binary-doped with antimony (Sb) and silver (Ag). The Sb/Ag-doped MoS 2 composite coatings showed an excellent solid lubrication performance with low and constant coefficients of friction of about 0.1 for a sliding time of 6 h. Estimations of the underlying wear rates revealed a reduction of the resulting wear rate by two orders of magnitude for the binary-doped Sb/Ag–MoS 2 composite coatings (2.43 ± 0.27 × 10 –7 mm 3 /Nm versus 2.70 ± 0.44 × 10 –5 mm 3 /Nm for un-doped MoS 2 coating), which reflects an outstanding wear resistance.
研究领域:
材料科学
·
表面工程
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2018
·Vol. 53
·期 12
·9340-9349
·
IF 2.993
Pan Haifeng,Shen Qi,Zhang Zinan,Yu Bihao,Lu Yushi
In the present work, a fire-blocking coating consisting of chitosan and molybdenum disulfide (MoS 2 ) was firstly deposited onto flexible polyurethane (FPU) foam by the layer-by-layer assembly technique. With the MoS 2 -filled coating, the FPU foam could burn without melt dripping during the whole combustion and keep its shape after combustion, while the pure foam was consumed completely. The analysis by thermogravimetric analysis/infrared spectrometry indicated that MoS 2 -filled coating could obviously reduce the amount of organic gaseous pyrolysis products and toxic volatiles during thermal decomposition of the foam. The cone calorimeter results indicated that the FPU foam with 8.5 wt% coating showed great reduction in peak of heat release rate (70%), peak smoke production rate (62.4%) and total smoke released (33.3%). Such a significant improvement in flame-retardant and the smoke suppression properties for FPU foam could be attributed to the protective effect of MoS 2 -filled coating.
研究领域:
材料科学
·
燃烧学
✓ 已验证
产品关联
DOI
高影响因子
LANGMUIR
·
2023
·
IF 3.9
Keli Wang,Xuan Zhou,Jian Liu,Xiaobo Wang,Xia Zhang
Ambient environment has a crucial effect on the lubrication performance of molybdenum disulfide (MoS2) coatings. In this work, we fabricated porous MoS2 coatings via a facile optimized aerosol-assisted chemical vapor deposition (AACVD) method. It is found that the obtained MoS2 coating demonstrates outstanding antifriction and antiwear lubrication performance with the coefficient of friction (COF) and wear rate as low as 0.035 and 3.4 × 10–7 mm3/Nm in lower humidity (15 ± 5)%, respectively, which is comparable to the lubrication ability of pure MoS2 in vacuum. In addition, the hydrophobic property of porous MoS2 coatings is suitable for infusing lubrication oil to achieve stable solid–liquid lubrication in higher humidity (85 ± 2)%. The composite lubrication system shows excellent tribological behavior in both dry and wet environments, which will alleviate the sensitivity of the MoS2 coating to the environment and ensure the service life of the engineering steel in complex industrial backgrounds.
研究领域:
材料科学
·
机械工程
·
表面工程
✓ 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）