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The present study investigates the evolution of texture components and strengthening mechanisms that lead to achieve better mechanical properties in multiwalled carbon nanotube (MCNT)-reinforced copper matrix (MCNT/Cu) composites with optimized electrical and thermal properties. Herein, a coupled wet chemical route - spark plasma sintering (WCR-SPS) process is employed to produce MCNT x /Cu composite powder (x = 0.5, 0.7, 1.0 and 1.5 wt%) that allows strengthening of Cu matrix. Among tested variants, the MCNT 1.0 /Cu composite exhibits presence of a strong (111)γ-texture along with homogenous dispersion of Cu coated MCNTs in Cu matrix and thereby delivering improved strength (282 MPa) and ductility (32%). The MCNT 1.0 /Cu composite variant also delivers an optimum thermal conductivity (287 W/mK), electrical conductivity (82.1% IACS), and excellent mechanical properties. Furthermore, advantage of the proposed strategy is demonstrated by comparing experimental values with the corresponding theoretical models. The structure-property correlation and contribution of related strengthening mechanisms are also discussed. [Display omitted] • Integrated MCNTs/Cu nanocomposites were synthesized by a coupled WCR-SPS process. • The presence of strong (111)γ-texture contributes to enhanced mechanical properties. • MCNT 1 /Cu composite exhibits improved strength with balanced conductivity. • The contributions of the different strengthening mechanisms are described. • Interface between Cu and carbon nanotubes has been investigated. [ABSTRACT FROM AUTHOR]

Abstract In this article, we report an active-matrix type Sn SnSb alloy, which is sandwiched between nitrogen doped reduced graphene oxide (N-rGO) sheets in the form of a nanocomposite, as a high rate capability anode for lithium-ion batteries. The alloy nanocomposite is synthesized via a cheap and industrially scalable route of microwave-assisted hydrothermal synthesis, and is coated onto electrodeposited 3D microporous nickel foam current collector. The additional mechanical buffering, along with effective electron conduction and lithium ion diffusion pathways provided by N-rGO nanosheets and nickel foam, result in a specific capacity of ∼300 mAhg−1 at a specific current of 4 A g-1 by preventing both pulverization and delamination of the active material. This combination of properties in N-rGO decorated Sn SnSb nanocomposite anode (with 40 wt% N-rGO) on nickel foam results in a 2nd cycle discharge specific capacity of 705 mAhg−1, with a stable reversible specific capacity of 500 mAhg−1 after 200 cycles @ 0.1 A g-1. The nanocomposite anode also shows capacity retention of 400 mAhg−1 @ 0.8 A g-1 (1C rate) for 120 cycles. As compared to low N-rGO (10 wt%) decorated nanocomposite, the high N-rGO (40 wt%) nanocomposite shows improved performance with a nominal sacrifice of capacity which is at par, if not superior, to the existing commercial graphitic anodes. Graphical abstract Image 1 Highlights • Synthesis of Sn SnSb N doped rGO composite is performed. • The structure of the composite is in the form of sandwich architecture. • Electrodeposited 3D microporous Nickel Foam is used as current collectors. • 40 wt% N-rGO composite shows the best rate capability as per the results. • Detailed study of the electrochemical performance of the composites is performed. [ABSTRACT FROM AUTHOR]

Ni-Co-nano SiC composite coatings were electrodeposited from a modified Watt's bath containing CTAB or SDS by pulse electrodeposition at four different peak current densities. The synergistic effect of the pulse peak current density and surfactant results in distinct morphological characteristics (characterized by SEM & TEM) and structural properties (characterized by XRD) producing nanocomposites with different mechanical (microhardness testing and nanoindentation testing) and electrochemical properties which can be traced to a multitude of factors such as nano SiC content and distribution, Cobalt content, grain refinement and texture. CTAB acts as a better dispersing agent for stabilising SiC nanoparticles compared to SDS, producing non-agglomerated SiC nanoparticles with a narrow size distribution. Increasing current density changes microstructure from spherical aggregates of polyhedral crystals (at 0.2 Acm −2 ) to uniform globular morphology (at 0.3 Acm −2 ) and finally to spherical aggregates (at 0.4 and 0.5 Acm −2 ), decreases cobalt content, increases SiC incorporation (up to a peak current density of 0.4Acm −2 ) and decreases coating thickness. Peak current density of the pulse electrodeposition is a vital factor in determining the crystallite size whereas both peak current density and nature of surfactant used are important factors in determining the texture. Electrodeposits with CTAB as surfactant provided higher values of hardness compared to SDS as surfactant, with C 3 having the maximum hardness of 582 VHN because of nanosized grains and uniform dispersion of nano sized SiC. Nanocomposite electrodeposited using SDS as surfactant at a peak current density of 0.3Acm −2 has the highest corrosion resistance with a corrosion current density of 0.47 μAcm −2 and polarization resistance of 120.37 KOhm cm −2 in 3.5 wt% NaCl solution. [ABSTRACT FROM AUTHOR]

In this study, a novel microbial green surfactant (lipopeptide surfactin) was utilized to facilitate the pulse electrodeposition of brushite (CaHPO 4 ·H 2 O) and hydroxyapatite (Ca 10 (PO 4) 6 (OH) 2) coatings on stainless steel (316 L SS). The addition of the biosurfactant and change in the current density (CD) affect the coating composition and its structural morphology. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy were performed to analyse the composition of the coatings. Without biosurfactant addition, the brushite phase is prevalent in the coatings with a minor content of hydroxyapatite. However, in the coatings deposited with biosurfactant as an additive, only the brushite phase is prominent suggesting that the biosurfactant inhibits the growth of the hydroxyapatite phase. Scanning electron microscopy (SEM) analysis reveals well-defined flower-like morphology for biosurfactant-assisted coatings, while the other coatings show a broom-like morphology. The addition of biosurfactant reduces the crystallite size along with the increased surface roughness and adhesion strength of the coatings. The cytocompatibility of the developed coating was assessed using the MTT assay with fibroblast cells (L929). Further, the cell adhesion, morphology the of cell and cell-coating interactions were evaluated using SEM. The corrosion resistance, in vitro degradation, antibacterial, antioxidant and antibiofouling properties, and hemocompatibility are improved due to the addition of biosurfactant to the electrolytic solution. Collectively, these results imply that the biosurfactant-aided brushite-coated surfaces can be used for bone regeneration, tissue engineering and biomedical applications. [Display omitted] • Brushite (BS) and BS-HAp coatings were developed on 316 L stainless steel. • The effect of current density and biosurfactant concentration have been discussed. • The formation mechanism of the BS and BS-HAp crystals have been proposed. • Biosurfactant-assisted coatings exhibit good electrochemical behavior. • Antibacterial and antibiofouling properties of the coatings have been discussed. [ABSTRACT FROM AUTHOR]

In the present course of study, mirror-bright silver (Ag) coatings are electrodeposited via pulse galvanostatic route from a cyanide-free thiosulphate-based bath containing cetrimonium bromide (CTAB) as a surfactant. Cyclic voltammetry (CV) and chronoamperometry studies are performed to analyze the mode of nucleation occurring in the presence and absence of CTAB during the deposition of Ag. The electrochemical studies and the corresponding SEM micrographs suggest that in the presence of CTAB, Ag nucleates in the progressive mode. The XRD and EDS analysis confirm the presence of elemental Ag in the deposited coatings. The SEM studies show the morphological variations that occur in the presence and absence of CTAB. The cross-sectional SEM suggests that in the presence of CTAB, a continuous and uniform coating of an average thickness of ∼3.5 µm is deposited. However, in the absence of CTAB, the deposited coating is non-uniform and has a lower thickness. A static immersion test in Na 2 S environment, followed by EIS measurements, are carried out to study the effect of CTAB on the anti-tarnishing behaviour of Ag coatings. The XPS spectra show that in the absence of CTAB there is a higher concentration of S(2p) and the coatings turn black due to the formation of tarnished layer over them. Therefore, it can be concluded that the coatings deposited in the presence of CTAB have a uniform and compact morphology and are less prone to tarnishing by the sulphide environment. On that account, the bath containing CTAB can be used for producing mirror-bright and tarnish-resistant Ag coatings for long-term aesthetic usage. [Display omitted] [ABSTRACT FROM AUTHOR]

In this article, we investigate into the ternary tin based alloy, thin film anodes for lithium ion batteries, specifically into Sn-Sb-Cu system, synthesized via electrodeposition. The alloy electrodes show a stable discharge capacity of ∼600 mAh g −1 discharged at a rate of 200 mA g −1 (∼0.3C) for 50 cycles. FESEM images show a nano-dendritic, porous microstructure which can help in accommodating high volume expansion during lithiation and prevent the problem of pulverization. The phases present in the prepared anodes are Sn, SnSb and Cu 6 Sn 5 which are all active towards lithium insertion and extraction. The behavior of this multi-phase alloy system is examined using X-ray diffraction measurements. At extremely slow discharge rates, the phases take up lithium at distinct potentials with reactions with SnSb, Cu 6 Sn 5 and Sn occurring at 0.86 V, 0.65 V and 0.45 V, respectively. A mechanism, where a lithiated phase decomposes and internally supplies lithium to the reacting phase, is observed and thereby lowering the total specific capacity of the anode as a whole when discharged. EIS measurements further reveal that there is degradation in the reaction kinetics with increasing cycles. Finally, failure of the anode is investigated and the cause is identified as the delamination of active material from the current collector. The problem is successfully removed by replacing Copper current collector with Silver current collector, where the intermetallic composition reacts at a lower voltage than Tin. Cycling the anode above this cutoff voltage removes the problem of delamination. However, it is identified that the existing electrolyte composition in the market, used for graphite anodes, is incompatible with Tin based anodes. [ABSTRACT FROM AUTHOR]

Inconsistent growth of tissues and poor osteoconduction performance on the metallic implant surfaces due to variation of surface energy are major contributing factors for failure of most metallic implant on account of lack of stronger attachment with surrounding bone or tissues. In this study, composite coating of hydroxyapatite, calcium hydrogen phosphate and MWCNT was developed on SS316 surface with varying amount of calcium phosphate-hydroxyapatite phase and crystallinity by pulsed electrodeposition. TEM study revealed that the MWCNTs were bonded strongly with the in situ deposition phases and thus act as reinforcement in the deposited coating similar to the collagen fiber in natural bone structure. Presence of MWCNT reinforcement increased the overall coating modulus of elasticity in the range of 6–10 GPa similar to that of natural bone. Different coating surfaces with varied amount of phase and crystallinity exhibits altogether different phenomena and growth geometry of apatite formation during osteoconduction period under contact with SBF. Coatings with highest amount of hydroxyapatite phase exhibit formation of porous spherical (~ 1 μm) and rod like (~ 600 nm) scaffold structure along with presence of nanopores (~ 100 nm) all along the contact surfaces. Cell proliferation study indicated uniform and fast spreading of cells over the coating surfaces as compared to bare metallic implant. EIS study illustrated five times high corrosion resistance capability along with formation of passivation layer under contact with SBF for coating comes with 66% of hydroxyapatite phase. [ABSTRACT FROM AUTHOR]

The orthopaedic implants for human body are generally made of different biomaterials like stainless steels or Ti based alloys. However, it has been found that from surface properties point of view, none of these materials is attractive for fast tissue or cell growth on the surface of implant. This is one of the most important criteria to assure quick bonding between implant and body tissues vis-à-vis minimum recovery time for the patient. Keeping in view of the above facts, this work involves the pulsed electro-deposition coating of biocompatible hydroxyapatite and its group compounds from a diluted bath of calcium and phosphate salt at various current densities over the biomaterial sheet of SS316. SEM study confirms different morphologies of the coatings at different current densities. Characterization techniques like X-ray diffraction, SEM with EDX and FTIR have been used to confirm the phase and percentage quantity of hydroxyapatite compound in the depositions. This coating can serve as a medium for faster tissue growth over the metallic implants. [ABSTRACT FROM AUTHOR]

The study describes the electrodeposition of mirror-bright Au coatings from a cyanide-free thiosulphate-based bath. The optimized composition of the electroplating bath contains chloroauric acid, sodium thiosulphate, cetyltrimethylammonium bromide (CTAB), 1,4-diazabicyclo[2.2.2]octane (DABCO), and nicotinic acid (NA). Quantum chemical calculations are carried out to study the electronic properties of various potential bath additives that can be used for the formulation of Au electroplating bath. Based upon these studies DABCO, and NA are selected as bath additives. The electrochemical impedance spectroscopy (EIS) study shows the electrochemical behaviour of the bath and the correlation of impedance values with the current density used. Deposition of Au is carried out from the formulated bath via pulse galvanostatic method at different current densities (10, 50, 100 and 200 mA/cm2) at a pulse frequency of 100 Hz and 50 % duty cycle. The XRD and EDS studies of the coatings confirm the presence of gold in its elemental form. The SEM studies, used for studying the effect of current density on the coating morphology, confirm that the coatings have a smooth and compact microstructure. The XPS study shows the atomic composition of the Au coatings. The nano-hardness tests show that the coating hardness decreases with an increase in current density. The coating deposited at 10 and 200 mAcm−2 has a hardness of 294 ± 11.3 and 190 ± 7.2 VHN, respectively. [Display omitted] • CTAB and NA are selected as complexing agents via quantum chemical calculations. • Au electroplating bath is formulated using CTAB, DABCO, and NA as basic bath additives. • Electrochemical studies provide an insight into the Au-complex reciprocity. • Compact, adherent, and mirror-bright Au coatings are developed via pulse galvanostatic route. • Hardness and the electrical contact resistance of the Au coatings are evaluated. [ABSTRACT FROM AUTHOR]

• The TRIP effect is predominant at lower strain rates. • An increase in the strain rate facilitates mechanical stability of austenite. • Excellent tensile properties are resulted at lower strain rates. In the present study, the effect of strain rate on the microstructure evolution and tensile behavior of intercritically annealed medium manganese steel is investigated. Tensile tests were performed on the annealed samples at strain rates of 1.33 × 10−4, 0.665 × 10−3 and 1.33 × 10−3 s−1. The amount of austenite to martensite transformation and dislocation density decrease with the increase in strain rates. The sample at the strain rate of 1.33 × 10−4 s−1 exhibits superior tensile properties due to the synergistic influences of the transformation-induced plasticity (TRIP) effect and high dislocation density. [ABSTRACT FROM AUTHOR]

In the current work, the microstructure evolution, mechanical stability of austenite and the micro-mechanical response of tensile deformed Fe-0.18C-4Al-7Mn (Wt%) steel are investigated. Interrupted tensile tests on the annealed samples (750 °C, 1 h) were performed at a tensile elongation of 5, 10, 20, 30, 40 and 60% to understand the deformation behavior and transformation-induced plasticity (TRIP) effect. Strain-induced martensitic transformation (SIMT) of reverted austenite is explored using X-ray diffraction (XRD), transmission electron microscopy (TEM) and electron backscattered diffraction (EBSD) analysis. The coefficient of mechanical stability of austenite (k -parameter) is quantified through the interrupted tensile tests using XRD analysis. Instrumented nanoindentation test was conducted on individual phases of the interrupted tensile-tested samples to determine their hardness and modulus values. The scanning electron microscopy (SEM) analysis reveals the gradual decrease in width and increase in length of austenite-martensite islands with an increase in the percentage of elongation. Evolution of dislocation lines, dislocation tangles and dislocation accumulations occur at ferrite grain boundaries and martensite lath boundaries during tensile deformation. The volume fraction of austenite decreases, and the transformation of austenite to martensite and dislocation density of austenite increase with the increase in the tensile elongation. Austenite is found to be mechanically more stable at 30% of tensile elongation due to the low austenite transformation ratio. Nanoindentation results show that the hardness increases with an increasing percentage of deformation. Multiple pop-ins are observed in load (P)–indentation depth (h) curves due to dislocation interaction at the interphase boundary. • Strain-induced martensitic transformation causes a decrease in austenite content • LAGB and GOS value increase with the increase in percentage of tensile straining • Using interrupted tensile tests, the value of the k -parameter is evaluated as 3.26 • Austenite is found to be mechanically more stable at 30% of tensile elongation • Presence of transformed martensite improves hardness of tensile-strained samples [ABSTRACT FROM AUTHOR]

The present study elucidates the electrodeposition of an Ag Cu bimetallic composite coating on a copper substrate from a thiourea-based (TU, CH 4 N 2 S) electroplating bath by pulse galvanostatic electrodeposition route. Electrochemical studies (LSV and EIS) demonstrate the metal-complex interactions and reduction mechanism of the bimetallic complexes occurring during the electrodeposition process. The pulse current transients provide insight into the deposition mechanism of the bi-metallic coating. X-ray diffraction studies of the electrodeposited coatings confirm the existence of both Ag and Cu without any solid solution phases. The SEM micrographs show that at higher current density there is a globular morphology of the deposits. Additionally, the proposed growth mechanism suggests the growth of higher index planes at the surface of the coating as the lower index planes gradually vanish. The coatings deposited at 1 and 5 mA/cm2 demonstrate a hardness of 382 ± 7.5 and 174 ± 5 VHN, respectively. Additionally, the coating also exhibits good adhesion to the substrate, examined by the pull-out test. The electrical resistivity studies show that the resistivity value of coatings is similar to that of bulk Ag. [Display omitted] • A novel thiourea (TU)-based electroplating bath is used. • LSV and EIS provide an insight into the metal-complex interactions. • Lower index planes vanish and higher index planes are stable on the coating surface. • The pulse galvanostatic route produces Ag Cu bimetallic coatings. [ABSTRACT FROM AUTHOR]

This work reports a facile method to fabricate copper-coated CNTs containing lamellar twins that deliver improved mechanical properties. The coating process is carried out via a wet chemical reduction method with molecular level mixing technique. Detailed optimization experiments reveal the effect of the reduction speed of the precursor on the morphology of the copper-based nanostructures and their efficacy in achieving uniform coating on the CNTs. The origin of the different nanostructures is studied via crystallographic simulation and supported by the LaMer mechanism. The prepared nanocomposites exhibit improved mechanical properties compared to pure Cu as well as other Cu-CNT based materials reported in the literature. The dependence of mechanical properties on the particle morphology of the precursor nanostructures is also examined. This improvement is due to the strong interfacial bonding between Cu and CNTs and the presence of lamellar twins in Cu, as observed from TEM analysis. The measured elastic modulus values of the nanocomposites are in good agreement with the values predicted by Halpin-Tsai and Shear-lag models. • Copper-coated CNT with lamellar twins by wet chemical route/molecular level mixing. • Spherical, nanorod & sea urchin morphology via simulated crystallographic analysis. • Effect of the reduction speed of the precursor on the morphological evolution. • Improvement in strength and elastic modulus of composite compared to literature reports. [ABSTRACT FROM AUTHOR]

Abstract: Synthesis of nanocrystalline ceria powders is carried out through the mixed fuel combustion approach by using different combinations of glycine and citric acid. The powders obtained with different fuel-to-nitrate (F/N) ratios are characterized by thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffraction (XRD), BET surface area analysis, and Raman spectroscopy. TGA and FTIR spectroscopy studies have revealed the presence of carbonaceous species and residual volatiles in the combustion synthesized ceria powders. It is observed that the variation of fuel-to-nitrate ratio has a profound influence on the carbonaceous residues from combustion, crystallite size (11–44nm), surface area (9–39m2/g) and morphology of the resultant powders. The Raman spectroscopy results on the variation of particle size with F/N ratio are consistent with the conclusions made from X-ray line broadening and BET surface area analysis. [Copyright &y& Elsevier]

• The in-situ dual matrix composite has been fabricated from the three different systems, i.e., Al-TiO 2 , Al-ZrO 2 and Al-TiO 2 -B 2 O 3 via mechanical and thermal synthesis process. • This unique microstructural concept of "composite within a composite" has been applied to enhance the thermal conductivity of the composite. • The thermal conductivity of composites with segregated microstructure is found to be 2 to 5 times higher than that of with a homogeneous microstructure. The dual matrix composites consisting of a reinforcement rich area (RRA) and reinforcement lean area (RLA) were fabricated incorporating in-situ process by powder metallurgy route. The RRA consists of milled Al-Al 2 O 3 -M (i.e., M is Al 3 Ti, Al 3 Zr or TiB 2), and RLA consists of mostly pure unmilled Al. For comparison, composite with single matrix having equivalent content of uniformly distributed reinforcement was also fabricated. The microstructure and thermal conductivity of single and dual matrix composites were compared. The dual matrix composites with the segregated morphology have shown a 2-5 times increase in thermal conductivity than single matrix composite with an equivalent amount of uniformly dispersed reinforcements. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Aluminum-based metal matrix composites reinforced with in situ Al3Ni and Al2O3 hybrid reinforcements are prepared by the mechanically activated, self propagating, high temperature synthesis (MASHS). The composites are fabricated from the powder blends consisting of aluminum and nickel oxide with different amounts of excess aluminum following the reaction scheme (2+ X)Al+3NiO→ XAl+Al2O3 +3Ni (where X =0, 5, 10 and 15moles). The onset temperature for the displacement reaction is brought down below the melting temperature of the mechanically activated powder blends by a high energy ball milling (HEBM). The solid-state displacement reaction can effectively preserve the nanostructure of the matrix with ultra fine reinforcements formed by the in situ reaction. It is demonstrated that the composite properties can be tailored by altering the stoichiometry of reactants. [Copyright &y& Elsevier]

In the present study, silver coatings are deposited from a novel cyanide-free thiosulphate-based electroplating bath containing cetyltrimethylammonium bromide (CTAB), 1,4-diazabicyclo[2.2.2]octane (DABCO), and pyridine-3-carboxylic acid (Niacin). LSV and EIS are carried out to demonstrate the metal-complex interactions and the reduction mechanism during electroplating. Depositions are carried out by both DC and pulse galvanostatic methods for comparison. XRD and EDS analysis confirmed the presence of elemental silver in the coatings. The SEM analysis and surface profilometry show the morphological variations and changes in surface roughness as a function of the electrodeposition route. Nano-indentation measurements reveal that the samples deposited under pulse conditions have a hardness of 196 ± 6.5 and 227 ± 15.6 VHN at current densities of 0.1 and 0.01 mA/cm2, respectively. By comparing the results obtained via both the deposition routes, it can be concluded that the pulse galvanostatic route can obtain a highly compact and adherent silver coating having a mirror-finish appearance that lasts for a long time under ambient indoor environment. Therefore, the developed bath can be used for producing mirror-bright silver coatings for aesthetic usage via pulse galvanostatic route. [Display omitted] • A novel thiosulphate-based electroplating bath is used. • LSV and EIS provide an insight into the metal-complex interactions. • The pulse galvanostatic route produces mirror-bright coatings. [ABSTRACT FROM AUTHOR]

• Synthesis of Al c /(Al f -TiB 2 -Al 2 O 3) dual matrix composite by in-situ technique with B 2 O 3 /TiO 2 mole ratio of 1. • Al c /(Al f -TiB 2 -Al 2 O 3) dual matrix composite shows a bicontinuous microstructure with reinforcement rich and lean region. • The mechanical and wear properties of the dual matrix composite is compared with single matrix composite. ga1 Three different in-situ Aluminum matrix composites (AMCs) were synthesized by mechanical thermal process via powder metallurgy route from Al–B 2 O 3 –TiO 2 system, where the B 2 O 3 /TiO 2 mole ratios were taken as 0, 0.5 and 1. The results show that the composite with B 2 O 3 /TiO 2 mole ratio of 1 exhibits the best mechanical properties among all the composites. Therefore, the mole ratio of 1 was used to synthesize the Al c /(Al f –Al 2 O 3 –TiB 2) dual matrix composite with segregated microstructure. This composite consists of two regions, namely reinforcement rich area (Al f –Al 2 O 3 –TiB 2 , where f stand for fine) and reinforcement lean area (Al c , where c stands for coarse), which form a bicontinuous microstructure giving a good combination of strength and ductility. For comparison, Al f –Al 2 O 3 –TiB 2 single matrix composite with an equivalent content of uniformly distributed reinforcement was also fabricated. The composites were characterized using DSC, XRD, SEM and TEM. The compression testing was conducted with a strain rate of 10−4 at RT, 150 and 450 °C. The ductility and wear resistance of Al c /(Al f –Al 2 O 3 –TiB 2) dual matrix composite improved in comparison to the Al f –Al 2 O 3 –TiB 2 single matrix composite due to its segregated bicontinuous dual matrix microstructure. [ABSTRACT FROM AUTHOR]

The effect of the addition of various amounts (1, 2 and 4 wt%) of copper-coated multi walled carbon nanotubes (CuCNT) on the mechanical (hardness, compressive strength and elastic modulus) and thermal (thermal conductivity and coefficient of thermal expansion) properties of two sets of aluminium matrix hybrid composites (AMHCs), i.e., Al- 30 wt % AlN and Al-30 wt % Y 2 W 3 O 12 has been investigated. The CNTs and AMHCs are fabricated using the molecular-level mixing and powder metallurgy route, respectively. The TEM analysis reveals that the CNTs are effectively coated with copper. The SEM characterization reveals that the CuCNTs are uniformly dispersed in the aluminium matrix. Experimental results reveal that the addition of CuCNT into the AMHCs increases the hardness, compressive strength, elastic modulus and thermal conductivity. Dilatometry studies reveal that the thermal stability of both the AMHCs increases with an increase in the amount of CuCNT as well as the number of thermal cycles. The coefficient of thermal expansion also decreases significantly with an increase in the amount of CuCNT in both the AMHCs. • Cu coated carbon nanotubes has been synthesized by molecular level mixing process. • Aluminium matrix hybrid composites were prepared using powder metallurgy route. • CuCNT along with AlN or Y 2 W 3 O 12 were added as reinforcement, respectively. • Effect of CuCNT on mechanical and thermal properties of AMHCs has been studied. [ABSTRACT FROM AUTHOR]

• Antimony alloy nanorods prepared using CTAB-assisted microwave-hydrothermal method. • Preferential adsorption of CTAB on (1 1 0) planes promotes nanorod formation. • Detailed TEM and XRD investigation support the proposed growth mechanism. • Practical application as anode in lithium-ion and sodium-ion full-cells. • Full-cells satisfy USABC specific energy-density benchmark for electric vehicles. Practical application of antimony alloy based electrodes in alkali-ion secondary batteries are viable due to their low-cost and widespread abundance. Employing unique nanostructuring strategies is vital for significantly improving their electrochemical performance while simultaneously addressing their inherent drawbacks. In this study, we report a simple microwave-hydrothermal approach for preparing antimony and tin-antimony alloy nanorods for the first time. Detailed X-ray diffraction and transmission electron microscopy measurements reveal that the preferential adsorption of cetrimonium bromide molecules on the (1 1 0) planes of the precursor alloy nanoparticles results in the formation of self-assembled nanorods with an average aspect ratio of 6. When mixed with nitrogen-doped graphene flakes, these nanorods deliver reversible discharge capacities of 500 mAh g−1 and 350 mAh g−1 at the end of 200 cycles in Li+ and Na+ half-cell configurations, respectively. When coupled with a LiNi 0.5 Mn 1.5 O 4 cathode, the resulting Li+ full-cell delivers a nominal working voltage of 4.3 V, a high energy density of 344 Wh kg−1 full-cell , and an 87.5% capacity retention after 200 cycles. Similarly, when coupled with a Prussian blue analog cathode, the resulting Na+ full-cell also delivers a nominal working voltage of 2.5 V, an energy density of 250 Wh kg−1 full-cell , and an 82.5% capacity retention after 100 cycles. [ABSTRACT FROM AUTHOR]

In this manuscript, we propose nickel antimony oxide (NiSb 2 O 6 , NSO), crystallized in the tri-rutile form, as a high capacity conversion-type anode material for the sodium-ion batteries. The material is synthesized via co-precipitation method followed by calcination at high temperatures. X-ray diffraction studies confirm the formation of a phase pure tri-rutile NSO powder after calcination at 1000 °C for 5 h. The as-prepared powder is then electrophoretically deposited on a copper foil along with carbon black as conductive additive to develop uniform, porous, and adherent NSO‑carbon black films. The deposited film is then tested as an anode for sodium-ion battery, which delivers a specific capacity of 255mAhg−1 after 50 cycles at a specific current of 100mAg−1, with a coulombic efficiency of ~98%. The deposited film also exhibits good cycling stability as well as rate capability. Furthermore, the film delivers a specific capacity of 140mAhg−1 after 100 cycles, when cycled at a higher specific current (750mAg−1). Unlabelled Image • NiSb 2 O 6 , a new Na-ion battery anode material is developed. • Electrophoretic deposition method is used to fabricate NiSb 2 O 6 ‑carbon black anode. • EPD grown electrodes exhibit good electrochemical properties. [ABSTRACT FROM AUTHOR]

In this work, we demonstrate the advantage of introducing extrinsic pseudocapacitance behavior in the active material for designing low-cost, high energy, and power density sodium-ion full cells. Here, tin and antimony based alloy nanopowder is synthesized via microwave assisted hydrothermal process (MAHP) for use as a negative electrode. Ex-situ x-ray diffraction studies reveal that the alloy nanopowder stores Na+ via a diffusion-controlled alloying mechanism. Extrinsic pseudocapacitance behavior is subsequently introduced by sandwiching the alloy nanopowder between nitrogen doped reduced graphene oxide nanosheets via MAHP. When coupled with a diffusion-controlled positive electrode comprising of an iron-based prussian blue analog, the resulting full cell demonstrates a high energy density of 262.5 Wh kg−1 at 1C rate with 85.7% capacity retention at the end of 100 cycles. Detailed cyclic voltammetry and electrochemical impedance studies provide insight into the effect of extrinsic pseudocapacitance in improving the electrochemical performance of the full cell. Image 1 • Sodium-ion full cell comprising of tin-antimony anode and prussian-blue analog cathode. • Effect of extrinsic pseudocapacitance on half cell and full cell performance. • Detailed cyclic voltammetry and electrochemical impedance spectroscopy studies. • Low-cost and environment-friendly active materials. • Microwave assisted hydrothermal synthesis. [ABSTRACT FROM AUTHOR]

Scaffolds play a crucial role in bone tissue engineering to support the defect area through bone regeneration and defect reconstruction. Promising tissue regeneration without negative repercussions and avoidance of the lifelong presence inside the body make bioresorbable metals prosper in the field of regenerative medicine. Recently, Zn and its alloys have emerged as promising biodegradable materials for their moderate degradation rate and satisfactory biocompatibility. Nevertheless, it is very challenging for cells to adhere and grow over the Zn surface alone, which influences the tissue-implant integration. In this study, an attempt has been made to systematically investigate the bioactivity responses in terms of in vitro hemocompatibility, cytotoxicity, antibacterial activity, and in vivo biocompatibility of newly developed Zn-2Cu-0.5Mn/Mg alloy scaffolds with different surface roughness. The rough surface of Zn-2Cu-0.5Mg shows the highest degradation rate of 0.16 mm/yr. The rough surface exhibits a prominent role in the adsorption of protein, further enhancing cell adhesion. Concentration-dependent alloy extract shows the highest cell proliferation for 12.5% of the extract with a maximum cell viability of 101% in Zn-2Cu-0.5Mn and 108% in Zn-2Cu-0.5Mg after 3 d. Acceptable hemolysis percentages (less than 5%) with promising anticoagulation properties are observed for all of the conditions. Enhanced antibacterial ( Staphylococcus aureus and Escherichia coli ) activity due to a significant effect of ions illustrates the maximum killing effect on the bacterial colony for the rough Zn-2Cu-0.5Mg alloy. In addition, it is observed that for rough Zn-2Cu-0.5Mn/Mg alloys, the inflammatory response is minimal after subcutaneous implantation, and neo-bone tissue forms in the defect areas of the rat femur with satisfactory biosafety response. The osseointegration property of the Zn-2Cu-0.5Mg alloy is comparable to that of the Zn-2Cu-0.5Mn alloy. Therefore, the rough surface of the Zn-2Cu-0.5Mg alloy has the potential to enhance biocompatibility and promote better osseointegration activity with host tissues for various biomedical applications.

This study presents a facile fabrication of 58S bioactive glass (BG)-polymer composite coatings on a 316L stainless steel (SS) substrate using the electrophoretic deposition technique. The suspension characteristics and deposition kinetics of BG, along with three different polymers, namely ethylcellulose (EC), poly(acrylic acid) (PAA), and polyvinylpyrrolidone (PVP), have been utilized to fabricate the coatings. Among all coatings, 58S BG and EC polymers are selected as the final composite coating (EC6) owing to their homogeneity and good adhesion. EC6 coating exhibits a thickness of ∼18 μm and an average roughness of ∼2.5 μm. Herein, EC6 demonstrates better hydroxyapatite formation compared to PAA and PVP coatings in simulated body fluid-based mineralization studies for a period of 28 days. Corrosion studies of EC6 in phosphate-buffered saline further confirm the higher corrosion resistance properties after 14 days. In vitro cytocompatibility studies using human placental mesenchymal stem cells demonstrate an increase in cellular viability, attachment, and higher proliferation compared to the bare SS substrate. EC6 coatings promote osteogenic differentiation, which is confirmed via the upregulation of the OPN and OCN genes. Moreover, the EC6 sample exhibits improved antibacterial properties against Escherichia coli and Staphylococcus aureus compared to the uncoated ones. The findings of this work emphasize the potential of electrophoretically fabricated BG-EC composite coatings on SS substrates for orthopedic applications.

In the field of bone tissue engineering, recently developed Zn alloy scaffolds are considered potential candidates for biodegradable implants for bone regeneration and defect reconstruction. However, the clinical success of these alloys is limited due to their insufficient surface bioactivities. Further, the higher concentration of Zn 2+ produced during degradation promotes antibacterial activity, but deteriorates osteogenic properties. This study fabricated an Azadirachta indica (neem)-assisted brushite-hydroxyapatite (HAp) coating on the recently developed Zn-2Cu-0.5Mg alloy to tackle the above dilemma. The microstructure, degradation behavior, antibacterial activity, and hemocompatibility, along with in vitro and in vivo cytocompatibility of the coated alloys, are systematically investigated. Microstructural analysis reveals flower-like morphology with uniformly grown flakes for neem-assisted deposition. The neem-assisted deposition significantly improves the adhesion strength from 12.7 to 18.8 MPa, enhancing the mechanical integrity. The potentiodynamic polarization study shows that the neem-assisted deposition decreases the degradation rate, with the lowest degradation rate of 0.027 mm/yr for the ZHN2 sample. In addition, the biomineralization process shows the apatite formation on the deposited coating after 21 days of immersion. In vitro cytotoxicity assay exhibits the maximum cell viability of 117% for neem-assisted coated alloy in 30% extract after 5d and the improved cytocompatibility which is due to the controlled release of Zn 2+ ions. Meanwhile, neem-assisted coated alloy increases the ZOI by 32 and 24% for Gram-positive and Gram-negative bacteria, respectively. Acceptable hemolysis (<5%) and anticoagulation parameters demonstrate a promising hemocompatibility of the coated alloy. In vivo implantation illustrates a slight inflammatory response and vascularization after 2 weeks of subcutaneous implantation, and neo-bone formation in the defect areas of the rat femur. Micro-CT and histology studies demonstrate better osseointegration with satisfactory biosafety response for the neem-assisted coated alloy as compared to that without neem-assisted deposition. Hence, this neem-assisted brushite-Hap coating strategy elucidates a new perspective on the surface modification of biodegradable implants for the treatment of bone defects.

Stainless steel (316L SS) has been widely used in orthopedic, cardiovascular stents, and other biomedical implant applications due to its strength, corrosion resistance, and biocompatibility. To address the weak interaction between steel implants and tissues, it is a widely adopted strategy to enhance implant performance through the application of bioactive coatings. In this study, Cu-doped brushite coatings were deposited successfully through pulse electrodeposition on steel substrates facilitated with a biosurfactant (BS) (i.e., surfactin). Further, the combined effect of various concentrations of Cu ions and BS on the structural, electrochemical, and biological properties was studied. The X-ray diffraction (XRD) confirms brushite composition with Cu substitution causing lattice contraction and a reduced crystallite size. The scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) studies reveal the morphological changes of the coatings with the incorporation of Cu, which is confirmed by X-ray photoelectron spectroscopy (XPS) and elemental mapping. The Fourier transform infrared (FTIR) and Raman spectroscopy confirm the brushite and Cu doping in the coatings, respectively. Increased surface roughness and mechanical properties of Cu-doped coatings were analyzed by using atomic force microscopic (AFM) and nanohardness tests, respectively. Electrochemical assessments demonstrate corrosion resistance enhancement in Cu-doped coatings, which is further improved with the addition of biosurfactants. In vitro biomineralization studies show the Cu-doped coating's potential for osseointegration, with added stability. The cytocompatibility of the coatings was analyzed using live/dead and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assays; cell adhesion, proliferation, and migration studies were evaluated using SEM. Antibacterial assays highlight significant improvement in the antibacterial properties of Cu-doped coatings with BS. Thus, the developed Cu-doped brushite coatings with BS demonstrate their potential in the realm of biomedical implant technologies, paving the way for further exploration.

Zinc (Zn) and its alloys are considered futuristic biodegradable materials for their acceptable mechanical properties, suitable corrosion rate, and good biocompatibility. In this study, we report newly developed biodegradable Zn-2Cu -x Mn/Mg ( x = 0, 0.1, and 0.5) alloys, aiming to achieve good mechanical strength with excellent elongation, desirable wear resistance, and suitable corrosion rate. The effect of Mn/Mg addition on the structural, mechanical, wear, and degradation behaviors of the Zn-2Cu- x Mn/Mg alloys was thoroughly investigated. Degradation and tribological behaviors of the alloys were explored in the presence of simulated body fluid (SBF), Dulbecco's modified Eagle medium (DMEM), and DMEM with a 10% fetal bovine serum (FBS) solution. Alloy elements and hot rolling improve their mechanical properties significantly due to precipitation hardening, grain refinement, and solid solution strengthening owing to the formation of MnZn 13 and Mg 2 Zn 11 phases. Among all the alloys, the Zn-2Cu-0.5Mn alloy achieved the highest ultimate tensile strength (UTS) of ∼405 MPa and yield strength (YS) of ∼293 MPa with an excellent elongation of ∼51%. The corrosion behavior of the alloys as determined by a potentiodynamic polarization study under different solutions follows the sequence Zn-2Cu < Zn-2Cu-0.5Mn < Zn-2Cu-0.1Mn < Zn-2Cu-0.1Mg < Zn-2Cu-0.5Mg. The corrosion rate by immersion testing for 30 and 90 days also follows the same sequence. The corrosion rate in different solutions follows the order SBF > DMEM + 10%FBS > DMEM. The addition of Mn/Mg also improves the wear resistance and slows the wear rate under wet conditions. The bending test results also indicate the highest bending strength of ∼375 MPa for the Zn-2Cu-0.5Mn alloy, among all the alloys. The bending and tensile strengths deteriorate continuously after the immersion for 30 and 90 days in the solution of SBF, DMEM, and DMEM + 10%FBS. Therefore, the Zn-2Cu- x Mn/Mg ( x = 0.1 and 0.5) alloys can be considered potential biodegradable implant materials.