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Abstract: By regulating the pH values of the reaction solution, the boehmite (γ-AlOOH) nanowires and nanoflakes were successfully synthesized with a simple hydrothermal route using anhydrous AlCl3, NaOH and NH3·H2O as starting materials. Crystalline γ-Al2O3 nanowires with diameter of 10–30nm and length of several hundreds of nanometer have been prepared by thermal decomposition of γ-AlOOH precursor. X-ray diffraction (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED), and high resolution transmission electron microscope (HRTEM) were used to characterize morphology and structure feathers of the synthesized samples. The pH values of the solution play important roles in the formation of γ-AlOOH nanowires. After calcinated at 500°C for 2h, the obtained γ-Al2O3 with a linear structure is similar to the γ-AlOOH precursor. [Copyright &y& Elsevier]

Abstract: Ni–Co–P hollow spheres (HSs) with different component ratios were fabricated by autocatalytic reduction method. With an increase of cobalt content, coercivity of hollow spheres increased because of Co hcp structure with high magnetocrystal anisotropy. The microwave properties of Ni–Co–P HSs were investigated in the range of 2–18GHz. Both permittivity and permeability of spheres–wax composites increased with the increase of cobalt content. For the Ni–Co–P hollow spheres, the minimum reflection loss (RL) (−41.7dB) was found at 6.3GHz with a thickness of 2.5mm. Additionally, with the increase of cobalt content, the minimal reflection loss increases obviously, which means that introducing Co into Ni improves the microwave absorption capability. [Copyright &y& Elsevier]

Abstract: Nickel–magnetite hollow spheres with the diameter about 150nm were prepared by an autocatalytic reduction method. The effect of Fe3O4 content in hollow spheres on microwave absorption properties has been investigated. With an increase of magnetite content, permittivity of sphere–wax composite decreased, while permeability increased. For composite layers, a minimum reflection loss (RL, −38.4dB) was predicted at 10.8GHz with a thickness of 2.5mm. In addition, the increasing content of magnetite resulted in the peak of RL moves to higher frequency and the minimal reflection loss increases obviously. [Copyright &y& Elsevier]

Abstract: Fe–36wt.%Ni alloy film was prepared through direct current electrodeposition to investigate the effect of 2-butyne-1,4-diol(BD) on the microstructure and internal stress of the deposited films. The deposits composition was not affected by the addition of BD when its concentration in the electrolyte was above 0.2g/L. All the film surfaces exhibited a flat and compact appearance. X-ray diffraction analyse revealed a phase of solid solution of iron in face centered cubic nickel, and the addition of BD caused strong (111) texture. The measurement of internal stresses showed a decrease of compressive stress with addition of BD in the electrolyte, and at the concentration of 0.4g/L, tensile stress showed up in the film and caused some micro-cracks parallel to the surface. [Copyright &y& Elsevier]

Abstract: The friction and wear properties of short carbon fibers (SCFs) reinforced aluminum matrix composite were studied. The influences of the fiber volume fraction, load applied, rotating speed, and wear mechanism were discussed. The results indicated that SCFs/Al composite had better tribological properties than Al alloy. The friction coefficient and wear mass loss decreased with the fiber volume fraction increased, but increased as the load and rotating speed increased, respectively. SCF reduced direct contact between the matrix and counterpart and improved the wear resistance of SCFs/Al composite greatly. The wear displayed a linear evolution in all the range of load. Surfaces before and after wear tests were characterized using scanning electron microscopy (SEM) and energy-dispersive analysis of X-ray (EDAX) spectroscopy. [Copyright &y& Elsevier]

Abstract: Ti-based brazing alloys were prepared by the non-consumable arc-melting technology. The wettability behavior of the brazing alloys on silicon carbide (SiC) was investigated by means of sessile drop method in vacuum at 1400°C for 10min. The brazing alloys of 91.5Ti–8.5Si (wt.%), 87.1Ti–8.1Si–4.8Cu (wt.%) and 83.2Ti–7.7Si–9.1Cu (wt.%) exhibit good wettability on SiC plate, but bad cohesion with SiC after cooling. However, the brazing alloys of 22Ti–78Si (wt.%) and 21Ti–74.2Si–4.8Cu (wt.%) exhibit both good wettability and cohesion with SiC after cooling. Microstructure, phase composition of the brazing alloys and the interface between the brazing alloys and SiC were investigated by using SEM coupled with EDS and XRD, respectively. [Copyright &y& Elsevier]

Abstract: Co–P-coated nickel hollow spheres (NHSs) were prepared by electroless plating technology. The morphology and component content of Co–P coating varies with the change of sodium citrate concentration in elctroless plating solution. And as phosphorus content increases in coatings, resulting in smaller grain, coercivity of microspheres decreases. The microwave absorption properties of spheres–wax composite were investigated in the range of 2–18GHz. Both permittivity and permeability increase with an increase of cobalt content in coatings. For composite layer, a minimal reflection loss (RL, −36.9dB) of was predicted at 8.1GHz with a thickness of 3mm. [Copyright &y& Elsevier]

Abstract: Three kinds of coatings, Ni, Cu and Al2O3, were obtained on the surface of short carbon fibers (SCFs). The interface characteristics and mechanical properties of SCFs/Al composites with the various coatings were systematically studied in this paper. The results showed that, compared to non-coating, Ni or Cu coating improved the wettability of SCFs and Al melt. However, the harmful phases Al3Ni or CuAl2 generated in interface zone and Al matrix result in the lower mechanical properties. Al2O3 coating protected the SCFs and prevented the harmful reaction of Al and SCFs. The interface of Al/Al2O3/SCF without any other phase was clean and well bonded, and the Al2O3-coated SCFs/Al composite had the highest mechanical properties. The interfacial indentation and fracture mechanism of all the composites were analyzed in detail. [Copyright &y& Elsevier]

This work developed intrinsically safe zinc–nickel batteries (ZNB) with different capacities of 20 Ah and 75 Ah, respectively, for future fundamental studies and applications. The developed ZNB has much better rate performance and higher mass and volume energy density than those of LAB. The application of the ZNB stacks as a power supply of an electric bicycle and a hybrid electric vehicle (HEV) is demonstrated. In addition, a solar power system and a 10 kWh ZNB energy storage system is built and tested to indicate the potential of ZNB in the application of energy storage devices. Interestingly, the ZNB has more economic advantages for the construction and operation of an energy storage system under high discharge rate. This work demonstrates the promising commercial application potential of ZNB and provides a new design methodology for energy storage. [Display omitted] • A zinc-nickel battery (ZNB) was developed to compare with lead-acid battery. • The application potential of ZNB for electric vehicles was demonstrated. • ZNB has been successfully integrated with energy storage systems. • The cost account of ZNB is calculated to compare with lead-acid battery. [ABSTRACT FROM AUTHOR]

Various strategies have been developed to fabricate mechanical robust superhydrophobic membranes on the original substrates. However, for superhydrophobic coatings that have to be homologous to the inherently fragile substrate, their mechanical stability problems have not been satisfactorily solved. Herein, we prepared three hierarchical superhydrophobic Cu coating via facile pulse electrodeposition with microstructure size of 10–15, 30–40, and 60–70 µm, respectively. The resulting superhydrophobic coatings simultaneously exhibit excellent self-cleaning, mechanical robustness, and corrosion resistance. A hydrophobic mechanism suitable for worn superhydrophobic surfaces was proposed, which can well analyze the influence of microstructure changes on wettability. Moreover, these three coatings can withstand 15, 50, and 100 cycles of sandpaper abrasion, respectively, as the size of the microstructure increases. The results demonstrate a size effect of microstructure, which means surfaces with larger-sized microstructures can better maintain their superhydrophobicity under mechanical damage. Our findings offer a reference for improving the mechanical robustness of other superhydrophobic coatings that are homologous to the substrate. [Display omitted] • Three superhydrophobic Cu coatings with mechanical robustness, self-cleaning, and corrosion resistance were fabricated. • A hydrophobic mechanism suitable for worn superhydrophobic surfaces was proposed. • The size effect of microstructure on resisting mechanical damage was investigated. • A strategy in improving the mechanical stability of fragile coatings homologous to the substrate was found. [ABSTRACT FROM AUTHOR]

• We provide a promising alternative cathode material for high-voltage thermal battery. • The NiCl 2 -based composite was prepared by hydrogen reduction strategy. • The NiCl 2 -based cell exhibits superior pulse discharge and fast activation ability. NiCl 2 is regarded as an ideal cathode material for high-voltage thermal battery. However, the difficulty of preparation and low inherent conductivity have become the major challenge to hinder practical application of NiCl 2 material. Herein, the reduced NiCl 2 with Ni as conductive agent has been developed via a facile hydrogen reduction. When served as cathode for thermal battery, the NiCl 2 -based composite exhibits high peak voltage of 2.51 V and short activation time of 0.67 s, accompanying with superior pulse discharge capacity. This work provides a promising alternative for high-voltage cathode and is beneficial to guide the further application of NiCl 2 materials. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes an investigation on an improvement of the interface between Al and short carbon fibers (SCFs) with α-Al2O3 coating by sol–gel technology. The composites of Al/uncoated SCFs and Al/α-Al2O3-**coated SCFs were fabricated successfully by vacuum press infiltration. The formation of α-Al2O3 coating during calcination was analysed by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). Scanning electron microscopy (SEM), energy-dispersive analysis of X-ray (EDAX) and transmission electron microscope (TEM) were used to observe the coated SCFs and the interface of composites. The results showed that the average thickness of the α-Al2O3 coating was about 200–250nm and the formation of Al4C3 at the interface between Al matrix and SCFs was controlled by the α-Al2O3 coatings. [Copyright &y& Elsevier]

[Display omitted] • A superhydrophobic hierarchical Cu cone-flower structure was fabricated. • Correlation of roughness skewness and void volume ratio to wettability was studied. • A new hydrophobic model was proposed to explain effect of structural parameters. Superhydrophobic films have been successfully prepared on various substrates by finely controlling surface micro/nanostructure's roughness and reducing surface energy. However, there is no unified conclusion about the correlation of surface roughness and 3D volume parameters to wettability. Herein, we fabricated a superhydrophobic film composed of hierarchical Cu cone-flowers via facile one-step pulse electrodeposition with a 30% duty cycle for 20 min. Based on this film, the relationship between roughness/volume parameters and hydrophobicity was well studied. The resulting cone-flower film exhibits excellent corrosion resistance and self-cleaning properties due to a high water contact angle (WCA) of ~160° and a low sliding angle (SA) of ~3°. The large roughness skewness (Rsk = 0.7–1.3) and void volume ratio (Vvc/Vmc > 1.5) are shown to be more desirable to achieve superhydrophobic surfaces. Moreover, a new hydrophobic model is proposed to explain the above results, which means that the nanoscale air cushions share most of the gravity of water droplets to help microscale air cushions closer to the Cassie state. Further experiments by adding or destroying the nanostructures to observe the change of hydrophobicity well verified our conjecture. [ABSTRACT FROM AUTHOR]

• Pure Zn and Zn-epoxy powder coatings was prepared by zincate electrodeposition. • The addition of epoxy powder improves microstructures and reduce roughness. • The incorporation of epoxy powder enhances the corrosion resistance. • The incorporation of epoxy powder hinders the hydrogen permeation. • The addition of epoxy powder improves the wear resistance. To improve the corrosion and wear resistance of the coating and reduce the effect of hydrogen penetration on the performance of galvanized steel, Zinc-epoxy powder (EP) composite coatings were prepared by alkaline zincate electrodeposition. The results show that the Zn-6 g/L EP coating has the lowest root mean square roughness of 281.99 A. The incorporation of EP enhances the corrosion resistance of the coating. The Zn-6 g/L EP coating has the largest coating resistance and charge transfer resistance. The incorporation of EP can hinder the hydrogen permeation, which may reduce the hydrogen embrittlement of galvanized steel. Tribological experiment shows that the wear resistance of the composite coating is improved. The friction coefficient and wear scar width of the Zn-12 g/L EP coating is the lowest. [ABSTRACT FROM AUTHOR]

To realize the potential application of the Co-DLC magnetic nanocomposite film in biosensor, it is necessary to obtain superparamagnetic property with high magnetization and good corrosion resistance in Co-DLC film. However, the cobalt carbide produced in the traditional preparation process will deteriorate the superparamagnetic property of Co-DLC film. To suppress the formation of cobalt carbide, strong magnetic target co-sputtering has been induced to prepare the Co-DLC nanocomposite films in this work. The results show that the cobalt particles are distributed in the amorphous DLC matrix. Most of cobalt exists in the form of metallic cobalt, and no cobalt carbide is formed during the film deposition process. The films maintain superparamagnetic property, which fits well with the Langevin equation. The saturation magnetization of the Co-DLC films increases with the increase of cobalt content, which reaches 0.068 T at cobalt content of 36 at. %. Meanwhile, when the cobalt content increases, the degree of graphitization of the film increases, which leads to a decrease in corrosion resistance of the film. Whereas, the polarization resistance of Co-DLC nanocomposite film is still higher than 1.03 × 105 Ω·cm2. The Co-DLC nanocomposite films with cobalt content between 29 and 36 at. % exhibit superparamagnetic property with high saturation magnetization and corrosion resistance. [Display omitted] • The method of strong magnetic target co-sputtering inhibits the formation of cobalt carbides in Co-DLC films successfully. • These films maintain superparamagnetic property, which is fitted well with Langevin equation. • The corrosion resistance of the Co-DLC film is above 10 times higher than that of the cobalt film. • The films with cobalt content between 29 and 36 at. % exhibit both high saturation magnetization and corrosion resistance. [ABSTRACT FROM AUTHOR]

Abstract: 22Ti–78Si(wt.%) eutectic braze was prepared through the non-consumable arc-melting technology. Wetting behavior of the braze on silicon carbide (SiC) was investigated by means of sessile drop method in vacuum at 1400 °C for 10 min. The result indicates that the braze exhibits good wettability (contact angle 25°) and adhesion with SiC. Main reasons are that TiC which owns higher surface energy is formed on SiC surface and the braze has an appropriate coefficient of thermal expansion (CTE) to that of SiC. [Copyright &y& Elsevier]

Abstract: Electroless plating of Cu–Ni–P alloy on polyethylene terephthalate (PET) fabrics and effect of plating parameters on the properties of alloy-coated fabrics were investigated. The deposition rate increased with the increase of temperature, pH and nickel ion concentration. The addition of K4Fe(CN)6 to the solution could reduce the deposition rate and make the deposits become more compact. The color of the deposits also had a corresponding improvement, changing from dark-brown to copper-bright with the addition of K4Fe(CN)6 to the plating solution. The deposits have an intensified copper (111) plane orientation with the addition of K4Fe(CN)6 to the plating bath. The surface electrical resistance of alloy-coated fabrics increased with increase of nickel ions concentration in the solution. The addition of K4Fe(CN)6 to the solution reduced significantly the surface resistance of alloy-coated fabrics. The conductive fabrics with high shielding effectiveness could be prepared at the optimum condition with 0.0038M nickel ions and 2ppm K4Fe(CN)6. As the deposit weight on the fabric was 40g/m2, the shielding effectiveness of alloy-coated fabrics was more than 85dB at frequency ranging from 100MHz to 20GHz. [Copyright &y& Elsevier]

K4Fe(CN)6 was used to improve the microstructure and properties of copper deposits obtained from hypophosphite baths. In electroless copper plating solutions using hypophosphite as the reducing agent, nickel ions (0.0038 M with Ni2+/Cu2+ mole ratio 0.12) was used to catalyze hypophosphite oxidation. However, the color of the copper deposits was dark or brown and its resistivity was much higher than that obtained in formaldehyde baths. The effects of K4Fe(CN)6 on the deposit composition, resistivity, structure, morphology and the electrochemical reactions of hypophosphite (oxidation) and cupric ion (reduction) have been investigated. The deposition rate and the resistivity of the copper deposits decreased significantly with the addition of K4Fe(CN)6 to the plating solution and the color of the deposits changed from dark-brown to copper-bright with improved uniformity. The nickel and phosphorus content in the deposits also decreased slightly with the use of K4Fe(CN)6. Smaller crystallite size and higher (111) plane orientation were obtained by addition of K4Fe(CN)6. The electrochemical current–voltage results show that K4Fe(CN)6 inhibited the catalytic oxidation of hypophosphite at active nickel sites and reduced the reduction reaction of cupric ions on the deposit surface by adsorption on the electrode. This results in lower deposition rate and a decrease in the mole ratio of NaH2PO2/CuSO4 consumed during plating. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a new method to prepare Al–8.5Fe–1.3V–1.7Si (FVS0812) alloy by spray co-deposition with added its over-sprayed powders was studied. Two kinds of powders which are different in particle size (≤43, 43–74μm) were used in the new process. Under the same experimental conditions, the alloys were produced by spray deposition without powders and the spray co-deposition. The deposited alloys were subsequently hot extruded with an extrusion ratio of 16:1 at 450°C. The results showed that the addition of over-sprayed powders refined the microstructure and improved the mechanical properties, and the effect of the fine over-sprayed powders was more evident than that of the coarse powders. The ultimate tensile strength was enhanced from 360.5MPa (without powders) to 433.3MPa (≤43μm) and 392.4MPa (43–74μm). The mechanical properties increase is mainly due to the over-sprayed powders pulverizing melt effectively, absorbing heat greatly and increasing the number of heterogeneous nuclei in matrix, which result in the enhancement of cooling rate and the refinement of microstructure. [Copyright &y& Elsevier]

Abstract: The composite electroforming technology was propounded to fabricate nano-sized carbide silicon particles (nano-SiC) reinforced copper composite. The surface morphology, microstructure, microhardness, wear resistance and electrical resistivity (E r) were examined. The results showed that nano-SiC were embedded in copper matrix uniformly and tightly. Comparing with the pure copper deposit, the surface of the composite was more fine, more compact and smooth, and the composite exhibited higher microhardness and better wear resistance. Besides, the change range of E r was small. [Copyright &y& Elsevier]

Abstract: Electroless copper plating on PET fabrics using hypophosphite as reducing agent was investigated. A continuous copper deposition could be obtained as the nickel ion concentration and temperature were more than 0.0030 M and 65 °C, respectively. The deposition rate increased obviously with the increase of temperature, pH and nickel ion concentration. Potassium ferrocyanide (K4Fe(CN)6) was used to improve the properties of the copper deposits. The addition of K4Fe(CN)6 to the plating solution could reduce the deposition rate and make the deposits become more compact, which led to lower surface resistance of copper-coated fabrics. The copper deposit had an intensified (111) plane orientation with the addition of K4Fe(CN)6 to the plating bath. The conductive fabrics could be prepared at the optimum condition with 0.0038M nickel ions and 2 ppm K4Fe(CN)6. As the copper weight on the fabric was 40 g/m2, the shielding effectiveness (SE) of copper-coated fabrics was more than 85 dB at frequency ranging from 100 MHz to 20 GHz. [Copyright &y& Elsevier]

Abstract: The silicon carbide particles (SiCp) dispersion-strengthened copper matrix composites (Cu/SiCp) were fabricated by composite electroforming technology. The microstructure, tensile property and wear behavior of Cu/SiCp composites were investigated. The results showed that composites with different SiCp contents were obtained. The microstructure of the composite presented a uniform distribution of SiCp in the matrix and good interfacial integrity. The hardness, yield strength and rigidity of the composites increased with increasing SiCp content, but at the cost of ductility. Increasing SiCp content in the composite was not always beneficial to the ultimate tensile strength and wear resistance. The ultimate tensile strength increased with SiCp content increasing up to 16 vol.% and decreased as exceeding 16 vol.%, and the wear mass loss decreased with SiCp content increasing up to 21 vol.% and increased again as exceeding 21 vol.%. [Copyright &y& Elsevier]

Abstract: Cu–graphite composites were prepared by electroforming technique in an acidic sulfate bath with graphite particles in suspension. Graphite particles change the regular surface structure of copper, increasing its microcrystallinity. The preferential orientation is changed from (200) plane to (220) plane. Wear resistance is improved after the incorporation of graphite particles into copper matrix. The wear mechanisms of copper and Cu–graphite composites are adhesive wear and delaminating wear, respectively. The corrosion behavior of the composites with different immersion time in 3.5% NaCl solution was studied using electrochemical impedance spectroscopy (EIS). Two equivalent circuits were adopted for the analysis of the impedance spectra. The changes in the corrosion mechanism after immersion in 3.5% NaCl solution are ascribed to the formation of Cu2O film on the surfaces of Cu–graphite composites. [Copyright &y& Elsevier]

Abstract: Electrodeposited nickel was prepared from a sulphamate bath at different current densities ranging from 0.01 A cm−2 to 0.1 A cm−2. Based on the analysis of the microstructure, the corrosion behavior of the electrodeposited nickel in 3.5%NaCl solution was studied using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). All the electrodeposits display active–passive–transpassive behavior in potentiodynamic polarization process. The electrodeposits with the best corrosion resistance are obtained at 0.05 A cm−2. As for other electrodeposits, the corrosion potential and breakdown potential decrease with increasing current density used to prepare electrodeposits. However, the variation of both corrosion current density and passive current density is opposite to that of the corrosion potential. The changes in the charge-transfer resistance determined from the impedance spectra are consistent with the results determined from potentiodynamic measurements. [Copyright &y& Elsevier]

Abstract: A new method of electrodeposition to prepare Ni/short carbon fibers (CFs) composites with network and sheet structures is described. The key point of the electrodeposition process is to obtain a sheet like preform floating on the electrolyte surface by froth flotation. The preform was composed of short homogeneous CFs. During the electrodeposition process, the preform was uniformly coated by nickel and the coating gradually grew from cathode to anode. The electrodeposits retained the network and sheet structures. The coating thickness can be controlled by appropriate electroplating conditions. The composites of epoxy resin reinforced by the electrodeposits were prepared successfully, and its electrical resistivity and electromagnetic shielding properties are reported. [Copyright &y& Elsevier]

Abstract: The hollow structural submicrometer-sized nickel spheres were successfully fabricated by the autocatalytic reduction method. Because of the metallic and ferromagnetic behaviour of the nickel spheres, the low-density microspheres could obtain high dielectric constant and magnetic loss in microwave frequencies. The abrupt variation of the real part and the sharp peaks of the imaginary part of permittivity and permeability were observed for the micrometer-sized and nanometer-sized nickel hollow spheres. Reflection loss less than −25dB were predicted over 11GHz with a thickness of 1.5–2.0mm. [Copyright &y& Elsevier]

Abstract: The tribological behaviour and wear mechanism of Ni–P–Gr (graphite)–SiC (manufactured by electroless plating) is surveyed in this paper. The worn surface, wear debris and the compositional changes that take place during wear were characterized using scanning electron microscopy (SEM) and energy-dispersive analysis of X-ray (EDAX). By comparison with Ni–P–Gr and Ni–P–SiC, the results indicate that hybrid Ni–P–Gr–SiC composite presented well anti-friction and wear resistance which is resulted from a graphite-rich mechanical mixed layer (GRMML) formed on the contact surface. Hard SiC particles mixed with GRMML played a load-bearing role at high load when relative motion occurs. After heat treatment at 400°C for 1h, the wear rate of the hybrid composite decreased with an increase in microhardness. During sliding, the temperature of the hybrid composite occured less change than Ni–P–SiC coating and further guaranteed the stable state of the whole wear process. [Copyright &y& Elsevier]

Abstract: In this paper, the friction behaviour and wear mechanism of electroless Ni–P matrix with PTFE and/or SiC particles composite coating are investigated by virtue of ring-on-disk wear machine at a high load of 150N. The worn surface, wear debris and the composition changes after wear were characterized using scanning electron microscopy (SEM) and energy-dispersive analysis of X-ray (EDAX). By comparison with Ni–P and Ni–P–SiC coatings, the results indicated that the combination of a PTFE-rich mechanical mixed layer (PRMML) formed on the worn surface and hard SiC were responsible for the good tribological properties of the hybrid Ni–P–PTFE–SiC composites at high load. After heat treatment at 400°C for 1h, the wear rate of Ni–P matrix composites decreased with corresponding increase in microhardness. During sliding, an obvious decrease in the temperature rise with PTFE addition was attributed to the good anti-friction of PTFE. [Copyright &y& Elsevier]

Abstract: A facile method to fabricate submicrometer-sized hollow nickel spheres by autocatalyzing the redox reaction around a sacrificial colloidal particle surface is presented in this paper. The size distribution of these spheres can be controlled by regulating the concentration of the alkali solution. The hollow nickel particles were characterized by field emission scanning electron microscopy, transmission electron microscopy and X-ray powder diffraction. The hollow spheres produced by this process may have potential applications in many fields, including chemistry, biotechnology and materials science. [Copyright &y& Elsevier]

The composite electroforming technology was propounded to fabricate silicon carbide powder (SiCp) reinforced copper-based composites. The influences of the concentration of SiCp in plating solution, the temperature of plating solution and current density on the SiCp content in Cu/SiCp composites were studied. Results showed that it could promote codeposition of Cu and SiCp and increase SiCp content in composites effectively through optimizing the technology parameters. Results of the study on thermal and mechanical properties of Cu/SiCp composites indicated that with SiCp content (vol.%) increasing, bend strength and HV (Vickers hardness) increased, but coefficient of thermal expansion (CTE) and conductivity factor decreased. In addition, internal stress existed in Cu/SiCp composites, which had influences on HV and thermal expansion property of Cu/SiCp composites. [Copyright &y& Elsevier]

[Display omitted] • Electrochemistry-driven adsorption approach was employed to selective capture Pb2+. • A@GO exhibited the enhanced selectivity of Pb2+ capture by applying electric field. • −0.2 V was an optimum potential in the adsorption selectivity operation. • Synergic effect was attributed to electric field and specific sites on TA@GO. Selective recovery of Pb2+ is always a high concern in the industrial application but challenging. Recycling Pb2+ as a sort of resource from contaminated water not only can significantly cut down the resource depletion but also reduce environmental pollution. Herein, a feasible electrochemistry-driven adsorption approach (ECDA) is employed to aid adsorbents for the selective removal of Pb2+ from metal-laden wastewaters. The distribution coefficient (K d) of Pb2+ on the conductive tannic acid-graphene aerogel (TA@GO) is 370.53 mL g−1 at −0.2 V which is 3 times that of the corresponding adsorbent (118.80 mL g−1) without applying a weak electric field. Compared with pure adsorbent, TA@GO achieves an enhanced selectivity coefficient (α) from 1.39 to 4.18 for Pb2+/Cu2+ at −0.2 V. The weak electric field can drive Pb2+ ions migrates rapidly from the bulk solution to the surrounding binding sites (phenolic hydroxyl) of adsorbent forming pre-aggregation, increasing the accessibility and availability of the active sites with target pollutants. And then a strong coordination interaction occurs between Pb2+ and the binding sites on TA. By applying different potentials, the selective properties of TA@GO can be tuned. Moreover, TA@GO shows a high selectivity coefficient of 12.44 for Pb2+/Cu2+ after being improving the electrical conductivity using electro-reduction, which is up to 2.5 times higher than the original TA@GO. We elucidated a new Pb2+ removal mechanism that involves a synergic effect by anchoring additional electric fields on functional adsorbents to improve the selective performance. This study highlights a novel direction for selective Pb2+ recovery by introducing electric fields onto adsorbents in practical application. [ABSTRACT FROM AUTHOR]

[Display omitted] Cation-disordered Li-excess oxides/oxyfluorides have opened the door for designing alternative, high energy cathodes. However, achieving long cycle life and high rate capability represents a major challenge for disordered rocksalt cathodes (DRX). Herein, we develop Li 2 Mn 3/4 Cr 1/4 O 2 F (LMCOF) DRX materials through a distinct redox mechanochemical method. The LMCOF contains trivalent Cr3+ and Mn3+, which allows for simultaneously accessing stable Mn/Cr dual redox at a narrow voltage window acceptable for conventional carbonate electrolytes. Coupled with the mitigated and reversible oxygen chemical changes, the LMCOF delivers high capacity, rate capability, as well as long cycle life upon extensive 1,000 cycles at various current densities. The multiscale synchrotron and neutron scattering, spectroscopic, and imaging analyses demonstrate that the capacity originates from the Mn/Cr dual redox with minimal contribution from oxygen redox, and that the good cycle life is attributed to the stable global crystal structure and local oxygen chemical environment. [ABSTRACT FROM AUTHOR]

Biofouling originated from ubiquitous bacteria has affected quantities of practical applications, such as biomedical devices, biosensors and marine industry, thus the design for anti-biofouling coatings has aroused great concern in the scientific community. However, current anti-biofouling strategies based on either the release of biocidal compounds or surface textured/chemical design (superhydrophobic grille) cannot satisfy the practical demands when encountering real-world complex conditions. Here we, inspired by the ferroelectric/piezoelectric effect, report a refreshing strategy to prepare anti-biofouling coatings. The BaTiO 3 particles are embedded in TiO 2 coatings by micro-arc oxidation of pure titanium, and the obtained coatings have marvellous antifouling performance against Gram-negative E. coli. The contact potential differences (CPD) and reactive oxygen species (ROS) are successfully induced by the spontaneous polarization of micro/nano BaTiO 3 , and then the BaTiO 3 -incorporated TiO 2 coatings (BaTiO 3 /TiO 2) can effectively resist fouling organisms. Our experiments demonstrate that the ferroelectric effect of coatings plays a crucial role in the antimicrobial mechanism. It is therefore believed that our design strategy could also guide the development of other anti-biofouling materials and bring a new era to the marine antifouling. [Display omitted] • The TiO 2 coatings embedded with BaTiO 3 particles exhibit excellent anti-biofouling performance. • The anti-biofouling performance of BaTiO 3 /TiO 2 coatings is attributed to the spontaneous polarization of embedded BaTiO 3. • The synergy of contact potential differences (CPD) and reactive oxygen species (ROS) can produce higher antibacterial effect. [ABSTRACT FROM AUTHOR]

Palladium catalysts have attracted widespread attention as advanced electrocatalysts for the formic acid oxidation (FAO) due to their excellent electrocatalytic activity and relatively high abundance. At present, electrodeposition methods have been widely developed to prepare small-sized and highly-dispersed Pd electrocatalysts. However, the customary use of surfactants would introduce heterogeneous impurities, which requires complicated removal processes. In this work, we reported a two-step electrochemical method that employed square-wave potential treatment (SWPT) to modify electrodeposited Pd particles without the use of capping agents. Under the SWPT with a mixed frequency, Pd particles show significantly reduced size and more dispersed distribution, exhibiting a high mass activity of 1.43 A mg−1 toward FAO, which is 4.6 times higher than the counterpart of commercial Pd/C. The increase in electrocatalytic activity of FAO is attributed to the highly developed surface of palladium particles uniformly distributed over the support surface. [ABSTRACT FROM AUTHOR]

• Zn-HEDP films were constructed on Q235 steel by coordination self-assembly. • Zn-HEDP films exhibit excellent corrosion resistance in 3.5 wt% NaCl solution. • The coordination between Zn2+ and HEDP can effectively improve the properties of Zn-HEDP films. • The assembly and protection mechanism of Zn-HEDP films are proposed by computational studies. Zinc coordinated 1-hydroxyethylidene-1,1-diphosphonic acid (Zn-HEDP) film was fabricated on steel surface by coordination self-assembly method. The surface morphology and chemical composition of Zn-HEDP film were investigated by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), and the structural and valence state of Zn-HEDP film was determined by Fourier transform infrared spectroscopy (FTIR), Raman spectra and X-ray photoelectron spectroscopy (XPS). The corrosion resistance of Zn-HEDP film in 3.5wt% NaCl solution was investigated by using potentiodynamic polarization curve and electrochemical impedance spectroscopy (EIS) techniques. The experimental results show that Zn-HEDP film is in a smooth surface with disturbed nanoparticles. The protection efficiency of Zn-HEDP film to steel in 3.5 wt% NaCl solution is firstly increased and then decreased with the increasing of zinc concentration, pH value and assembly time. The optimum preparation conditions for Zn-HEDP film are the zinc concentration of 10 mmol/L, pH value of 5.0 and assembly time of 30 min, under which the protection efficiency of film is reached to 95.79 %. The coordination between zinc ions and HEDP can effectively increase the binding energy with Q235 steel. Zinc ions can improve the compactness and thickness of Zn-HEDP films as bridging agents, which prevent Q235 steel from corrosive solution. [ABSTRACT FROM AUTHOR]

Cu-MBT@HNTs/epoxy self-healing coating was fabricated by using epoxy resin and Cu-MBT@HNTs nanocomposite inhibitor, which composed by halloysite nanotubes (HNTs) with containing 2-mercaptobenzothiazole (MBT) and Cu-MBT encapsulated end stopper. The surface morphology, static contact angle and adhesion force of Cu-MBT@HNTs/epoxy coating were observed and detemined by optical microscopy, static contact angle and pull-off adhesion tester, and the release behavior of MBT from Cu-MBT@HNTs was determined by UV–Vis spectrophotometer. The corrosion and self-healing behavior of Cu-MBT@HNTs/epoxy coating in 3.5% NaCl solution was evaluated by electrochemical impedance spectroscopy (EIS) technique. The experimental results show that MBT is successfully loaded into HNTs with a loading capacity of 12.3(wt.) %, and the formation of Cu-MBT end stopper could reduce the release rate of MBT in water especially in the acidic and neutral water. The prepared Cu-MBT@HNTs/epoxy coating has a smoother morphology, larger static contact angle and higher adhesion force than that of MBT@HNTs/epoxy coating. With the addition of Cu-MBT@HNTs, the scratched Cu-MBT@HNTs/epoxy coating has a higher polarization resistance and a better self-healing performance than that of blank epoxy coating and MBT@HNTs/epoxy coating, which resulted from the release of MBT inhibitor from HNTs by the local alkaline condition and the formation of Fe-MBT inhibition film on the scratched area of steel substrate. Unlabelled Image • Cu-MBT@HNTs controlled the release of MBT in response to alkaline environment. • Cu-MBT@HNTs were distributed uniformly in epoxy and reduced the hydrophilicity of coating. • C u -MBT@HNT s /epoxy coating exhibited self-healing behavior under damage. [ABSTRACT FROM AUTHOR]

• Superhydrophobic surface is prepared by secondary anodic oxidation (SAO) process. • The SAO process simultaneously constructs and modifies the rough structure. • Inhomogeneous surface energy leads to the formation of volcano-like structure. • Hydrophobic ability is enhanced significantly by the modified micro-/nanostructure. • Excellent water repellence and self-cleaning ability are obtained. Superhydrophobic surface has been extensively applied in the field of self-cleaning and corrosion prevention, and the common preparation route of the superhydrophobic surface involves the construction of rough structure and modification with low-surface-energy regents in multistep process. Herein, a facile one-step method was proposed to fabricate the superhydrophobic surface with the simultaneous construction and modification of hierarchical microstructure and surface, the volcano-like anodic aluminium oxide (AAO) -based superhydrophobic surfaces with controllable roughness were synthesized via secondary anodic oxidation (SAO) process of AAO film in an organic–inorganic sol–gel system. During the SAO process, the perfluorooctyl triethoxysilane, which covalently bonded onto the surface, resulted in the inhomogeneous distribution of surface free energy and heterogeneous generation of volcano-like structure. The hydrophobic ability was enhanced by the rough hierarchical micro-/nanostructure with low surface energy, and the TiO 2 /PFOTS-AAO-15 exhibited the optimal water repellence with a WCA of ~154°, self-cleaning performance and anticorrosion property in corrosive medium. This convenient method is anticipated to unlock various superhydrophobic surfaces on different substrates in the practical fields of self-cleaning and anticorrosion. [ABSTRACT FROM AUTHOR]

The rational design and synthesis of hybrid-type electrode nanomaterials are of significant importance for their diverse applications, including their promising usage as high-efficiency nanoarchitectures for supercapacitors (SCs) as a class of promising energy-storage systems for powering next-generation electric vehicles and electronic devices. Here, we report a regulated synthesis of eutectic structured Ni 3 S 2 /NiS nanorods, which is demonstrated to have fantastic electrochemical performance as a freestanding electrode for hybrid SCs. The as-prepared Ni 3 S 2 /NiS significantly increases the interfacial atomic activity between Ni 3 S 2 and NiS, which provides more electrochemical active sites and facilitates fast ion diffusion. The Ni 3 S 2 /NiS electrode presented superior areal specific capacity of 1330 μA h cm−2 and remains 67.1% of its initial capacity when the current density increased 20 folds. The as-assembled hybrid supercapacitor demonstrated fantastic energy density of 0.567 mWh cm−2@4.251 mW cm−2, and retained at 0.476 mWh cm−2@34.440 mW cm−2 with long durability. This study provides a facile pathway to rationally design a variety of eutectic structured metal compounds for high performance energy storage devices. Image 1 • Eutectic Ni 3 S 2 /NiS nanorods with enriched grain boundaries are synthesised. • Ni 3 S 2 /NiS exhibits abundant active sites and enhanced electronic conductivity. • The synergistic effect contributes to improved electrochemical performance. • Ni 3 S 2 /NiS exhibits high specific capacity, superior rate capability and stability. [ABSTRACT FROM AUTHOR]

• DL-EPR was used to describe the precipitation of carbides in super Cr13 stainless steel. • The main reason for the decrease in impact toughness is the precipitation of continuous Cr-rich carbides (M23C6) along the interface. • Solution treatment before quenching and tempering treatment can improve the impact toughness. • The impact tough of the steel can be predicted by DL-EPR. Super martensitic stainless steel (SMSS) is characterized by improved mechanical properties and corrosion resistance. However, during production the impact toughness will be significantly reduced under certain heat treatment regimes (tempering at 873 K followed by quenching at 1213 K and tempering at 913 K). Double loop electrochemical potentiokinetic reactivation (DL-EPR) were used to investigate the mechanism for the reduction of impact toughness in this experiment. It was found that the primary cause for the decrease was precipitation of continuously distributed Cr-rich carbides (M 23 C 6) along martensite lath boundaries. The Ra value obtained by DL-EPR is positively correlated with the amount of Cr-rich carbide precipitation. As Ra increases, impact toughness increases first and then decreases rapidly, which indicates that it is reasonable to use Ra to qualitatively predict the impact toughness of the steel. [ABSTRACT FROM AUTHOR]

• PASP-Zn films were constructed on Q235 steel by coordination self-assembly. • PASP-Zn films can improve the corrosion resistance of Q235 steel significantly. • Corrosion resistance is related to PASP/Zn ratio, pH value and assembly time. • The assembly and protection mechanism of PASP-Zn films are proposed. In this work, an economical and environmentally friendly polyaspartic acid-zinc (PASP-Zn) film was successfully prepared on the surface of Q235 steel by coordination self-assembly, and the preparation conditions of PASP-Zn film were optimized by single factor method. The surface morphology and thickness of PASP-Zn film were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM), and the structure and composition of PASP-Zn film were determined by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). The corrosion resistance of PASP-Zn film on Q235 steel in 3.5wt % NaCl solution was analyzed by electrochemical impedance spectroscopy (EIS) and polarization curves. The results show that PASP film and PASP-Zn film are successfully prepared on the surface of Q235 steel, and the single PASP film is self-assembled monolayers with thin thickness and loose structure. Whereas PASP-Zn film shows a rough morphology, accompanied by appearance of a large amount of nanoparticles, and the thickness of PASP-Zn film is about 98.0 nm. PASP-Zn film exhibits much better corrosion protective performance than PASP film in 3.5 wt % NaCl solution, and the highest protection efficiency can reach 94.48 %. The excellent coordination ability between PASP and zinc ions can effectively improve the compactness and thickness of PASP-Zn film, and prevent the corrosive ions from contacting the Q235 steel surface. By adjusting the preparation conditions, a PASP-Zn film with optimal corrosion resistance was prepared in the film-forming solution containing PASP/Zn ratio of 1:8 and pH value of 5.0 for 30 min. [ABSTRACT FROM AUTHOR]

Alcohol Oxidation: Air-Assisted Transient Synthesis of Metastable Nickel Oxide Boosting Alkaline Fuel Oxidation Reaction (Adv. Keywords: alcohols oxidation reactions; metastable; nickel oxide; oxygen vacancies; transient thermal shock EN alcohols oxidation reactions metastable nickel oxide oxygen vacancies transient thermal shock 1 1 1 12/10/20 20201208 NES 201208 In article number 2001397, Yanan Chen, Yida Deng, and co-workers report the fabrication of metastable NiO nanoparticles on carbon cloth (NiO@C/CC) via an air-assisted thermal shock technique (ATS-tech) as an efficient alcohol oxidation reaction catalyst. Alcohols oxidation reactions, metastable, nickel oxide, oxygen vacancies, transient thermal shock. [Extracted from the article]

During the 120 years' development route of the nickel-based cathode, lots of efforts have been made to realize alkaline batteries with better performance. From the earliest Edison's nickel-iron battery to the modern nickel-based battery, progress is always accompanied by backtracking steps, exhibiting a spiral-rising feature. In the early researches, composition and structures of cathodes gained most of the attention while since the 21st century, the morphology of the active materials has taken most of the research areas. Although the research interests varied with the development of technology, the core issues in material science still exist and cause unfavored problems, including insufficient energy density, limited cyclability, and inadequate rate performance. This review mainly focuses on describing a comprehensive development story of the nickel-based cathode and explaining the reasons for technology alteration. In the end, issues needed attention for future researches are presented to provide practical guidance. Image 1 [ABSTRACT FROM AUTHOR]

A supersaturated solid solution layer with a fine-grained size of 30–50 μm was formed on a nickel–aluminum bronze via laser surface quenching technology, and its corrosion resistance was improved by 42.6%, which was attributed to the homogenized element distribution and the formation of a more protective film during corrosion process. • The microstructure of as-cast NiAl bronze was refined by laser surface quenching. • Selective phase corrosion was eliminated for the uniform element redistribution. • Corrosion rate decreased 42.6% after laser surface quenching. • Enhanced corrosion resistance was ascribed to formation of a more protective film. Laser surface quenching technology was utilized to modify the surface microstructure of as-cast nickel-aluminum bronze. A supersaturated solid solution layer with a fine-grained size of 30–50 μm was formed, and its corrosion behavior was studied by electrochemical measurements and long-term immersion corrosion test. It was found that laser surface quenching homogenized the distribution of elements in the constituent phases and eliminated the selective phase corrosion. Due to the formation of a more protective film on laser quenched NAB alloy, the corrosion rate reduced about 42.6% compared with that of as-cast NAB alloy. [ABSTRACT FROM AUTHOR]

Impressive performance of the superhydrophobic coatings has attracted a wide research attention. In this study, a titanium dioxide-fluorosiloxane superhydrophobic coating has been developed on the stainless steel plates via brush coating of the sol. The surface morphology, surface roughness and chemical composition of the coating were systematically studied by cold field emission scanning electron microscope (SEM), 3d microscope and X-ray photoelectron spectroscopy (XPS), respectively. The self-healing ability and mechanism for the coating were analyzed in a chloride ion environment, and the electrochemical behaviors were studied by the polarization curves and electrochemical impedance spectroscopy (EIS). The results indicate that the superhydrophobic surface is slightly damaged after anodic polarization and reprocessing, yet it is noted to maintain its superhydrophobicity. [ABSTRACT FROM AUTHOR]

Abstract: An ultrafine-grained surface layer was fabricated on a pure Fe plate by the shot peening process. The average grain size within the surface layer of 10μm thick is about 28nm. The diffusion kinetics of Al was measured by secondary ion mass spectrometry within a temperature range of 300–380°C. The diffusion coefficient of Al in the nanocrystalline layer is about 4 orders of magnitude higher than that in coarse-grained Fe. The activation energy of Al diffusion in nanocrystalline layer is 1.38eV, which is much smaller than that reported for Al diffusion in the conventional Fe. The enhanced diffusivity of Al may originate from a considerable amount of nonequilibrium grain boundaries and a high density of dislocations in the surface layer processed by shot peening. [Copyright &y& Elsevier]

Abstract: Ni hollow spheres (NHSs) have been successfully synthesized through a microemulsion–template–interface reaction route. The structures of NHSs were characterized by X-ray powder diffraction (XRD), selected area electron diffraction (SAED), transmission electron microscopy (TEM). The results showed that the size of the NHSs was between 50 to 150nm. The shell thickness of the NHSs is about 20nm. In our method, the metal precursor and reducing agent dissolved in two different phases; they can react at oil/water interface. Thus, hollow spheres can be fabricated more easily. [Copyright &y& Elsevier]

• SAM for detecting the localized corrosion degree of the metal under the rust layer is firstly reported. • Combined TAMI scanning with image processing method, the pitting depth can be characterized. • Under the C-scanning mode, one single pit on the 7050 aluminum alloy can be focused. • This work provides practical methods on mechanism study of the localized corrosion process. To evaluate the residual life and safe operation of metallic materials, it is crucial to accurately identify the intensity and depth of corrosion pits. Scanning acoustic microscopy (SAM) using tomographic acoustic microimaging (TAMI) under C-mode was employed to determine corrosion pit morphology and depth on aluminum alloy 7050, and the reults were cross-checked by optical microscopy. Maximum and average pitting depths of 204 μm and 80 μm, respectively, were determined by multilayer scannning, and a pitted area of 30 ∼ 40 % was calculated using binary image processing. [ABSTRACT FROM AUTHOR]

Organic porous materials-TiO2/Cu composite (OPMTC) were readily fabricated through two steps, which included the formation of organic porous materials (OPM) and the in-situ synthesis of TiO2/Cu composite (TiO2/Cu) in the pore of OPM. Furthermore, the photocatalytic degradation behaviors of the photocatalysts toward organic pollutants were also investigated under simulated and nature sunlight, respectively. Finding showed that OPMTC allowed methyl orange, phenol, and methylene blue to be decomposed under simulated sunlight by the rate of 91.6%, 98.6%, and 100%, even to degraded DMF with a rate of 74% that revealed excellent photocatalytic degradation properties toward organic pollutants. Interestingly, OPMTC still kept the photocatalytic degradation ability after 6 time reuse. These results indicated the potential applications of OPMTC in the treatment of wastewater. Besides, the measurements of free radical intensities including superoxide free radical (O2·), singlet oxygen (1O2), and hydroxyl radical (·OH) of photocatalysts attributed to understanding the mechanism. The tested finding indicated that metallic copper doped TiO2 are beneficial to produce more free radicals thereby increasing photocatalytic degradation performances TiO2/Cu. OPMTC also had absorption ability measuring by BET that increased the contract area between photocatalyst and organic pollutants, thus, combining the two advantages thereby resulting in improving photocatalytic degradation properties. [ABSTRACT FROM AUTHOR]

• A layer of dodecyl phosphate (DDPO4) film on LY12 aluminum alloy substrate was prepared. • P was enriched at the SAMs/oxide layer interface, revealing that the P O bond in the DDPO4 adsorbed on oxide surface. • The prepared film showed superior corrosion resistance in the chloride-containing solution. The goal of this work was to prepare a layer of dodecyl phosphate (DDPO4) film on LY12 aluminum alloy substrate for corrosion protection using self-assembly technique. The prepared DDPO4 Film properties were characterized by X-ray photoelectron spectroscopy (XPS), water contact angle measurement, and electrochemical measurement. Experimental results indicated that DDPO4 was successfully assembled on aluminum alloy substrate via covalent bond attachment. The modified surface was hydrophobic due to the DDPO4 attached to the oxide surface and a hydrocarbon tail-up orientation. Accelerated corrosion test showed that the DDPO4 modified LY12 aluminum alloy substrate exhibited excellent corrosion resistance in an electrolyte containing 0.01 M Cl− + 0.01 M SO 4 2−, and no apparent corrosion pits were observed after an exposure of 96 h. The charge transfer resistance of the DDPO4 covered aluminum alloy was ∼100 times larger than that of the blank aluminum alloy. [ABSTRACT FROM AUTHOR]

A novel, boltless and easily assembled zinc–air battery configuration is developed to compare with the conventional configuration commonly used in most academic studies. A zinc–air battery with a boltless configuration can fundamentally avoid the man-made leakage risk by sealing the internal environment via mechanical fasteners on the battery body and enhancing the cell capacity by modifying the battery configuration. The volume energy density and the mass energy density of zinc–air battery stacks with five zinc–air batteries in series are 117.3 Wh L−1 and 68.0 Wh kg−1, respectively, both exceeding those of commercial lead-acid batteries. This study simulates the static and dynamic application of zinc–air battery stacks as a power supply for an electric motorcycle and a single flow battery energy storage unit, showing high commercial application potential in mobile power supply and scale energy storage. Image 1 • A boltless zinc–air battery configuration with good sealing effect is developed. • Man-made leakage risk of zinc–air battery caused by uneven stress is avoided. • Developed configuration has higher mass efficiency than conventional configuration. • Developed zinc–air battery has greater energy density than lead-acid batteries. • Potential of zinc–air batteries in electric motorcycle is demonstrated. [ABSTRACT FROM AUTHOR]