Materials
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2020
·Vol. 13
·期 5
·1135
·
IF 3.057
Lei Zha,Heping Li,Ning Wang
TC11 alloy is a promising structural material, and has a wide range of applications in many corrosive and high temperature hydrothermal systems. The passive film has an important influence on its electrochemical behavior. In this study, in-situ electrochemical methods (that is, open circuit potential (OCP), linear polarization (LP) and electrochemical impedance spectroscopy (EIS)) were used to monitor the long period electrochemical behavior of TC11 alloy in 0.01 M Na2SO4solution at 300 °C/10 MPa. The growth kinetics of the passive film was mainly studied. The correlation between the evolution of the electrochemical behavior and the growth of the oxide film was discussed. The results showed that although the OCP gradually stabilized after twenty thousand seconds, henceforth the polarization resistance (Rp) was still increasing due to the thickening of the passive film. An equivalent circuit was proposed to fit the EIS experimental data, leading to determination of film capacitance and film resistance. Besides, the electrochemical data was interpreted in terms of the point defect model (PDM). The EIS results are consistent with theRpresults.Keywords:TC11 alloy;passive film;time;high temperature and pressure;EIS;PDM
研究领域:
材料科学
·
电化学
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产品关联
DOI
PubMed
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Xin Lv,Hongbo Zhao,Yisheng Zhang,Zefan Yan,Yu Zhao,Hong Zheng,Wenqing Liu,Jianping Xie,Guanzhou Qiu
Although pyrite bio-dissolution plays an important role in the processing of sulfide ores, the formation of passivation film inhibited the further dissolution of sulfide ores. In order to enhance the dissolution of sulfide ores, a novel method for destroying the passivation film using ozone was proposed and verified. The generated passivation film inhibiting pyrite dissolution in the presence of Leptospirillum ferrooxidans and Acidithiobacillus thiooxidans was studied. The X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) results indicate that a passivation film mainly consisting of jarosite and polysulfide (S n n− /S 0 ) might be formed during biotic stage, which can be eliminated with the introduction of ozone (2 g/min) in 30 min. Electrochemical results show that ozone significantly increased the electrochemical reactivity of passivated pyrite, further proving that ozone enhanced the dissolution of passivated pyrite through destroying the passivation layer. Hence, a bi-stage method for dissolution of sulfide ores can be proposed.
研究领域:
微生物学
·
矿物加工工程
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DOI
PubMed
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Chun Bai,Shuxian Liu,Fenghai Ma,Shasha Lu,Junmei Wang,Shaodong Liu
As a new structural building material, carbon fiber-reinforced concrete has very good flexural strength, wear resistance and impermeability. However, because carbon fiber is a good conductor, the durability of reinforced concrete structures may be affected if it comes into contact with steel bars in the concrete, thus allowing the formation of a galvanic couple. In this paper, electrochemical tests and corrosion weightlessness experiments were carried out in a pore fluid of concrete with a pH of 12.5. The results showed that when carbon fiber was coupled with carbon steel, the double layer capacitance (C dl ) increased and the charge transfer resistance (R ct ) decreased. The thickness of the passivation film decreased, and the protective performance of the passivation film on the carbon steel decreased. Moreover, the corrosion potential of the carbon steel increased, the corrosion current density increased, and the corrosion rate of the carbon steel increased. An XPS analysis confirmed the results of the electrochemical experiments. After carbon fiber coupling, the ratio of Fe 3+ /Fe 2+ on the surface of the carbon steel decreased, and the stability of the passive film on the surface of the carbon steel decreased. Although coupling with carbon fiber had a negative effect on the passivation of the carbon steel, the surface of the carbon steel could still maintain good passivation in a chloride-free simulated pore fluid environment.
研究领域:
土木工程
·
材料科学
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DOI
高影响因子
CORROSION SCIENCE
·
2020
·
IF 6.479
Yang Du,Mingyin Kou,Jiguo Tu,Mingyong Wang,Shuqiang Jiao
The electrochemical behavior of TiB 2 anode is investigated in the present work in order to obtain the anodic behavior in molten CaCl 2 -CaO. The work reveals that the passivation film is generated on the surface of TiB 2 anode during the anodic polarization process, leading to a higher pitting potential than that of the Pt electrode. After 100 h potentiostatic electrolysis, the TiB 2 anode shows a corrosion rate as low as 1.38 × 10 -3 g cm -2 h -1 . The formation mechanism of the TiB 2 anode passivation film after electrolysis is determined as TiB 2 + O 2- → Ti(BO 3 ) + O 2- → TiO 2 + CaO → CaTiO 3 .
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
JOM
·
2019
·Vol. 72
·期 2
·658-664
·
IF 2.305
Shen Zheng-Jun,Lin Yan,Zhang Yan-Nan,Rong Ju,Yu Xiao-Hua,Zhan Zhao-Lin
The porosity of a self-lubricating chromium-free passivation film is evaluated by means of a novel finite element model and structural parameter, λ ( λ represents the porosity of passive film). The applicability of this equivalent model is validated via thin-film thermocouple measurements and laser interferometry. Our results revealed that the roughness of the film can be improved by a lubricating filler. A value of λ = 0.25 yielded the optimal friction and wear characteristics of the self-lubricating chromium-free passivation film. This optimal condition corresponded to temperature values and stress values of 77.99°C (theoretical) and 81.24°C (experimental), and 1.67 × 10 5 Pa (theoretical) and 1.65 × 10 5 Pa (experimental), respectively. The close correspondence between the experimental and the theoretical results indicate that the model is reasonable.
研究领域:
材料科学
·
机械工程
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DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Yuhan Yao,Zhaolin Zhan,Jianxiong Liu,Xiao Wang,Xiaohua Yu,Ju Rong
Response surface methodology (RSM) was used in this study to determine the optimum operating conditions for the reduction of galvanized sheet corrosion using a Cr-free passivation films. Passivation films layer with strong corrosion resistance was formed on the surface of galvanizing which was impregnated in chromium-free passivating agent. Furthermore, the RSM was used to ascertain the main and interactive effects (deviation between the experimental and theoretical values: 0.12%). The coefficient of determination (R 2 ) showed that the RSM approach was appropriate for optimization of the Cr-free passivator. Silane coupling agent, ammonium molybdate, nanosilica, and tannic acid played a key role in changing the corrosion area and potential. The results revealed that, compared with Cr 6+ passivation, Cr-free passivation yielded considerably more homogeneous and smoother surfaces (surface roughness of Cr-free passivation film: 0.54 μm). In addition, the properties of the zinc coating after Cr- free passivation were clearly superior to those of the zinc coating subjected to the conventional Cr 6+ passivation treatment. E corr, current density, and polarization resistance values of this superior coating were -1073 mV, 0.017 A cm -2 , and 989.2 Q, respectively. This study can serve as an experimental and a theoretical guide for the development of Cr-free passivation films.
研究领域:
材料科学
·
电化学
·
表面工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
Weihao Fan,Huaiyuan Wang,Chijia Wang,Zhanjian Liu,Yanji Zhu,Kaka Li
CeO 2 -PANI conductive polymer capsules were prepared by in-situ chemical oxidation polymerization. The capsules were dispersed in F51 epoxy resin and then sprayed onto the steel surface to form novel coatings after curing. The corrosion resistance of coatings was investigated by EIS in a 3.5 wt% NaCl solution. After 30 days, the 60-μm-thin coating containing CeO 2 -PANI capsules exhibited the highest corrosion resistance, and its impedance modulus was higher than 10 9 Ω·cm 2 , which was 10 times that of conventional PANI-Epoxy coatings. This improvement was attributed to the (Fe 3 O 4 + γ-Fe 2 O 3 + CeO 2 ) passive film actively formed by the synergistic effect of PANI and Ce 3+ ions. PANI polarized the anodic reaction and Ce 3+ inhibited the cathodic reaction.
研究领域:
材料科学
·
腐蚀工程
·
聚合物化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2020
·
IF 8.247
Shuangshuang Lin,Haiming Hua,Jiyang Li,Peng Zhang,Jinbao Zhao
We have found that the formation of passivation film plays a major role in the negative shift of the decomposition voltage in the hydrogen-generating process. Both the hydrolysis of weak acid ions and the decarboxylation reaction of carboxylate can make the LiCO 2 CH 3 produce a passivation film to inhibit the water decomposition to a certain extent. As for the LiCO 2 CF 3 without hydrolysis of weak acid ion, it can be highly possible to facilitate the introduction of CO 2 via its carboxylate specific decarboxylation reaction, and further produce lithium carbonate passivation film as well. However, the water decomposition voltage in the oxygen-producing process is more dependent on the properties of lithium salt anions. Those with strong electron-absorbing groups such as the trifluoromethyl are more likely to effectively endue the aqueous electrolyte with a high oxidative decomposition potential . Moreover, the concentration of LiCO 2 CF 3 aqueous electrolyte can reach up to 28 mol kg −1 , and hence the electrochemical stability window of this water-base electrolyte can be expanded to about 3.0 V. This work provides a new idea for the selection of high concentration lithium salt.
研究领域:
电化学
·
材料科学
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产品关联
DOI
高影响因子
JOM
·
2023
·
IF 2.6
Zhu Yanshaozuo,Shen Xixun,Chen Qian,Xu Qunjie
A silicate and phosphate composite passive film on zinc was prepared from a composite passivation solution containing zinc dihydrogen phosphate and sodium metasilicate. The morphology, composition, valence and functional groups of the passive film with different passivation times were analyzed through field-emission scanning electron microscopy (FE-SEM), energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and infrared spectroscopy to understand its evolution process. The passive film exhibits a cyclic film-forming process with a periodic ratio of silicate and phosphate, which is caused by the periodic changes in the alkalization degree of the interface between the electrode and the solution. Such periodic film-forming process promotes the passive film growth and makes the passive film uniform and dense. Electrochemical analysis, immersion tests and copper sulfate spotting tests illuminate that the composite passive film is more corrosion-resistant than the pure silicate passive film. This composite passivation film exhibits a uniform corrosion behavior with gradually expanding micropores due to the effective inhibition of inward diffusion and permeation of chloride ions by the dense film structure of cyclic growth, which avoids the pinhole corrosion and improves the protection of the passivation film.
研究领域:
材料科学
·
电化学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Zhangyi Huang,Jiaochun Zheng,Yutong Zhang,Yang Shi,Junjing Duan,Ruichong Chen,Tiecheng Lu,Zhijun Wang,Jianqi Qi,Haomin Wang
Gd 2 Zr 2 O 7 (GZO)-based ceramic waste form has attracted broad interest due to its potential applications in the long-term disposal of high-level nuclear waste . However, its high-capacity isomorphic immobilization and leaching mechanism are not well understood yet. Herein, GZO-based waste form with a single pyrochlore phase and homogeneous element distribution, achieving an isomorphic waste load as high as 50 wt%, was fabricated successfully. Isomorphism failure of the waste form is due to the Ln 6 MoO 12 (Ln is lanthanides) formation and direct precipitation of PdO from the oversaturated solid solution. Chemical durability tests showed that the 42-day leaching rates of nearly all elements in the waste form with the maximum waste load were only between 10 −6 and 10 −5 gm −2 d −1 . The leaching of 0.5SW·0.5GZO over a period of 42 days is primarily controlled by dissolution, leading to a gradual restructuring of the surface in two distinct stages: the formation of an amorphous passivation film and the agglomeration of amorphous precipitates. Notably, the formation of the amorphous passivation film stands as the primary factor influencing the leaching rate of the waste form.
研究领域:
核废料管理
·
材料科学
·
放射性废物处理
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产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2025
·
IF 6.3
Xinquan Zhang,Jingtian Ye,Yongjie Zhang,Yuxi Xiao,Jun Yang,Hui Deng
To eliminate surface defects in copper-based microstructures produced through micromachining technology and to further decrease surface roughness, subsequent polishing treatments are essential for the fabricated microstructured components. Electrochemical polishing (ECP) is a noncontact polishing method that minimizes surface damage. Nevertheless, traditional copper ECP methods have limitations such as complex electrolyte compositions, low polishing efficiency, and difficulties in achieving nanoscale roughness. Currently, research on ECP for copper primarily focuses on process optimization, due to the limited understanding of the morphology and composition of intermediate products formed during the process. This study presents a comprehensive approach involving the development of a sulfuric acid/methanol electrolyte for the ECP of copper. Process parameters were optimized to increase the efficiency of copper polishing. Additionally, a new polishing model was proposed to elucidate the material removal mechanism of copper. The formation and removal rates of the passivation film were faster at the high points, and this results in differences in the material removal rates at high and low points, thereby achieving polishing. Under optimal conditions, the Sa surface roughness of copper was reduced from 83.5 nm to 2.6 nm within only 3 min. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) revealed that the passivation film primarily consisted of Cu 3 (SO 4 ) 2 (OH) 2 ·2H 2 O and CH 3 CuS. This research demonstrates that ECP offers a promising method for efficiently and effectively polishing copper to high standards.
研究领域:
材料科学
·
电化学
·
表面工程
·
纳米技术
·
微加工技术
✓ 已验证
产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2025
·
IF 6.1
Junru Gao,Qiangsong Wang,Liyan Dong,Jinchun Ren,X.I.N.L.U. CHAI,Kexing Song
Material corrosion is a critical factor leading to structural failure, performance degradation, and significant economic losses, particularly in harsh marine environments. Therefore, enhancing the corrosion resistance of metallic materials is crucial for extending equipment service life, ensuring operational safety, and reducing maintenance costs. This work elucidates the passivation mechanism of 1,2,3-benzotriazole (BTA) on B30 cupronickel (Cu 30Ni alloy, UNS C71500) through integrated electrochemical analysis and 28-day artificial seawater immersion testing. XPS characterization revealed a multi-component passivation layer (20–30 nm thickness) comprising Cu(I)-BTA organometallic compounds, Ni(II)-BTA chelates, and crystalline Cu₂O domains. The optimized BTA treatment enhanced surface hydrophobicity, evidenced by a 20 % increase in water contact angle (85° → 102°). Electrochemical polarization demonstrated remarkable corrosion current density suppression from 18.5 μA/cm 2 (bare alloy) to 0.504 μA/cm 2 (passivated), indicating two-order-of-magnitude improvement. Long-term immersion tests at 25 °C showed 87 % reduction in corrosion rate (0.0114 → 0.0015 mm/a). The synergistic effects of organic-inorganic hybrid film formation and hydrophobicity enhancement establish BTA passivation as a viable eco-friendly alternative to chromate treatments for marine alloy protection.
研究领域:
材料科学
·
腐蚀工程
·
表面化学
·
电化学
·
海洋工程
✓ 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）