Display omitted
Corrosion experiments and theoretical calculations were performed to investigate the inhibition mechanism of indazole (IA) and 5-aminoindazole (AIA) for copper in NaCl solution. The ...results obtained from weight loss and electrochemical experiments are in good agreement, and reveal that these compounds are high-efficiency inhibitors with inhibition efficiency order: AIA>IA, which was further confirmed by field emission scanning electronic microscope (FESEM) observation. Besides, the quantum chemical calculations and molecular dynamics (MD) simulation showed that both studied inhibitors are adsorbed strongly on the copper surface in parallel mode. The adsorption of these molecules on copper substrate was found to obey Langmuir isotherm.
Display omitted
•NCDs effectively suppress copper corrosion in aggressive acid medium.•NCDs can be designated as a modest cathodic-type inhibitor.•The NCDs–adsorption film involves both physisorption ...and chemisorption.
Researchers recent reported that N-doped carbon dots (NCDs) effectively inhibit steel corrosion in HCl solution, whereas the action mechanism is still uncertain to date. Herein, novel NCDs have been prepared using a facile hydrothermal method. Combining electrochemical, weight loss, and micromorphology techniques, the resultant NCDs were found to effectively suppress copper corrosion in aggressive H2SO4 medium. NCDs–adsorption film was formed on copper substrate as a barrier that could prevent transportation of corrosive particles. The relevant anticorrosion mechanism of NCDs was proposed in detail, which could provide powerful guidance to design and synthesis new nanomaterials for metal protection from corrosion.
•Four allyl imidazolium-based ionic liquids are used as green inhibitors for copper corrosion in sulfuric acid.•The inhibition efficiencies of the investigated inhibitors increase with the augment of ...alkyl chain length attached to the imidazolium ring.•The order of inhibition ability obtained from EIS is in perfect agreement with the polarization results.•Theoretical calculations provide favorable support for the experimental data.
In this work, four allyl imidazolium-based ionic liquids (ILs) with various length of alkyl chains were developed for the corrosion inhibition of copper in 0.5M sulfuric acid. Electrochemical techniques, morphological characterization, theoretical caculations were combined to investigate the inhibition performance and mechanism. The results show that corrosion circumstance of copper in sulfuric aqueous solution is efficiently inhibited by these ILs. Their favorable performance is ascribed to formation of ILs-adsorption films, which follow the Langmuir adsorption isotherm. Besides, the inhibition efficiencies of the investigated inhibitors increase with the augment of alkyl chain length attached to the imidazolium ring.
Display omitted
•Two novel long-chain indazole derivatives were synthesized and then fabricated on copper surface.•DDIA-SAMs containing double alkyl-chain tails harbor more superior inhibition ...performance for copper corrosion than DI-SAMs.•The inhibition mechanism was elucidated via DFT calculation.
Two novel long alkyl-chain indazole derivatives namely, 1-dodecyl-1H-indazole (DI), N,1-didodecyl-1H-indazol-5-amine (DDIA), were synthesized and fabricated on copper surface. Comprehensive characterizations were used to evaluate the appearance and structural properties of studied SAMs, implying a more stable and hydrophobic film of DDIA than IA. The anticorrosion ability of the SAMs was investigated by electrochemical methods allied to an immersion test, which suggest that DDIA-SAMs harbor more superior inhibition performance than IA ones. Besides, Fukui functions indicates that N2 and N10 in DDIA molecule are likely to form coordinate bonds with Cu atoms, whereas N2 in DI is the active site during absorption process.
Display omitted
Food flavors of 2-isobutylthiazole (ITT) and 1-(1,3-Thiazol-2-yl)ethanone (TEO) for the corrosion inhibition of X65 steel in H2SO4 were studied by electrochemical methods, atomic ...force microscopy (AFM), scanning electron microscopy (SEM) and theoretical calculations. Electrochemical experiments show that ITT and TEO can effectively inhibit the corrosion of cathode and anode of X65 steel, and they are mixed-type corrosion inhibitors. Surface topography analysis (SEM and AFM) also visually demonstrate that ITT and TEO form an effective barrier film on the X65 steel surface to isolate the corrosive medium. Theoretical calculations profoundly explain the inhibition mechanism of ITT and TEO at the molecular level. In addition, the adsorption behavior of ITT and TEO on the surface of X65 steel is consistent with Langmuir isotherm adsorption. The results of experimental and theoretical studies have shown that the inhibition effect of TEO is better than ITT for X65 in 0.5 M H2SO4.
Display omitted
•Convenient in-situ preparation strategy of MgAl-LDH coatings on Mg was proposed.•The prepared superhydrophobic coating has long-lasting anti-corrosion performance.•The anti-corrosion ...mechanism of MgAl-LDH coatings modified by different long-chain molecules has been clarified.
Layered double hydroxides (LDHs) have been widely used as “smart” containers in the field of metal corrosion protection, and have broad industrial prospects. It is environmentally friendly and feasible to use aliphatic carboxylates and corresponding acids as substitutes for harmful corrosion inhibitors. However, previous studies rarely involved comparing the anti-corrosion mechanisms of different aliphatic acids modified on the LDH surface, and the durability of the prepared coatings also needs to be improved. In this work, MgAl-LDH laminates were grown in situ on AZ31 substrates by a hydrothermal method, and then modified by sodium laurate (SL) and sodium dodecylbenzene sulfonate (SDBS). Due to the physical barrier effect of the LDH layers, the spatial repulsion effect of the air film and the ion exchange reactions in the interlayer galleries, the functional coatings prepared exhibit smart and superior anti-corrosion performance on the magnesium substrates in 3.5 wt.% NaCl solution. Compared with LDH-SDBS-8 coating, the obtained superhydrophobic LDH-SL-8 coating shows more excellent long-term corrosion protection owing to the stronger intercalation capacity.
Display omitted
•Novel green maple leaves extract (MLE) was debuted for the corrosion-related studies.•The inhibition efficiency of MLE is significantly improved with the addition of KI.•The mixture ...of MLE/KI can form a stable protective film, following the Langmuir adsorption isotherm.•Theoretical calculation exhibits the large binding energy between MLE molecules and Fe substrate.
In recent years, many plant extracts have been used as green corrosion inhibitors to replace traditional corrosion inhibitors, but their inhibition performance still needs to be improved. The synergistic corrosion inhibition behavior and mechanism of maple leaves extract (MLE) and potassium iodide (KI) on Q235 steel in 0.5 M H2SO4 solution were firstly investigated in this work. The results demonstrate that both MLE and KI can prevent the corrosion of steel in corrosive media, and that their combined protection effect is superior. The corrosion inhibition efficiency (η) value reaches 93.4 % in corrosive solution with the combination of 200 mg/L MLE and 200 mg/L KI, while the maximum of η is only 81.6 % using MLE alone. In addition, Fe-N bond and Fe-O bond were found on the steel surface through the X-ray photoelectron spectroscopy (XPS) analysis, which confirm the formation of a protective film. The adsorption behavior of an inhibitory film composed of MLE and KI mixtures onto steel surface follows the Langmuir adsorption isotherm model, consisting of physisorption and chemisorption. Finally, molecular dynamics (MD) simulation indicates that inhibitor molecules can adsorb on the Fe substrate in a parallel way with high binding energy values, which supports the experiments well.
Display omitted
•Electrochemical test data indicate the order of inhibition efficiency: DPT > DDP > PDF.•The XPS results show that SCu bonds are generated in PDF, DDP and DPT, and NCu bonds are ...detected in DDP and DPT.•The DPT, DDP, and PDF adsorb on the Cu surface in accordance with the Langmuir model.•Quantum chemistry research and molecular dynamics simulation provide in-depth understanding of the experimental results.
Phenyl disulfide (PDF), 2,2′-dithiodipyridine (DDP), 5,5-dithiobis(1-phenyl-1H-tetrazole) (DPT) were studied as inhibitors for Cu in H2SO4 via electrochemical methods, surface morphology analysis and theoretical calculations. Electrochemical experiments show that PDF, DDP and DPT can exhibit excellent corrosion inhibition performance. Their order of corrosion inhibition is DPT > DDP > PDF. Surface morphology analysis supports the electrochemical results. The X-ray photoelectron spectroscopy (XPS) results show that SCu bonds are detected in PDF, DDP and DPT, and NCu bonds are detected in DDP and DPT. PDF, DDP and DPT adsorption on the Cu surface obey the Langmuir isotherm model. The results of quantum chemical calculations show that DPT has more active reaction sites than DDP and PDF. Molecular dynamics simulation results show that the order of binding energies of the three corrosion inhibitor molecules on the copper surface is DPT > DDP > PDF.
Display omitted
•A novel solid slippery surface was successfully designed and fabricated.•The solid slippery surface showed good stability and anti-corrosion performance.•The interface erosion ...mechanism was revealled via electrochemical and surface analysis techniques.
Metal corrosion is a headache in marine industry. The existing technologies can hardly provide an effective long-term corrosion protection. Biomimetic slippery lubricant infused porous surface (SLIPS) has been developed as a potential alternative technique to resolve this problem. Herein, a stable triple-layered slippery surface which consist of compact-nickel-underlayer/porous-nickel-midlayer/PDMS/paraffin infused toplayer was designed and developed for corrosion protection. This composite surface exhibited a low sliding angle with good stability and thermal assitant self-healing property. Simultaneously, it demonstrated good anti-corrosion property with an extremly low corrosion current density and a large impedance of 2.301 × 107 Ω·cm−2, the as-prepared sample even can provide efficient corrosion protection for a long-term immersion in NaCl solution. Furthermore, the interface erosion mechanism was studied via the assistance of electrochemical and surface analysis techniques. The results revealed that no corrosion products were generated which further proved the good anti-corrosion performance. We believe that this triple-layered slippery surface can broaden the application of metals in the field of marine and other industries.
A novel Mn
3
O
4
/Co(OH)
2
cactus-type nanoarrays were directly grown on nickel foam, by a simple two-step process, using an electrodeposition and a hydrothermal process. Mn
3
O
4
particles were used ...as a backbone anchoring Co(OH)
2
to form a cactus-type nanoarray structure. Owing to the synergistic effect of Mn
3
O
4
nanosheet arrays and Co(OH)
2
, the as-obtained Mn
3
O
4
/Co(OH)
2
electrode displays an excellent specific capacitance of 1792.9 F g
−1
at a current density of 1 A g
−1
. Furthermore, the assembled Mn
3
O
4
/Co(OH)
2
//reduced graphene oxide asymmetric supercapacitor delivers a high energy density of 53.4 Wh kg
−1
at a power density of 800.0 W kg
−1
, as well as outstanding cycling performance (82.5% retention after 2000 cycles at 10 A g
−1
). These excellent properties make Mn
3
O
4
/Co(OH)
2
a favorable candidate for high-performance supercapacitors.
PDF
