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In this paper novel in situ one-step simultaneous anaphoretic deposition process of amorphous calcium phosphate (ACP) and titanium oxide (TiOx) with and without chitosan oligosaccharide lactate (ChOL) on titanium substrate was performed. The coatings were investigated by SEM, XRD and FTIR techniques, whereas roughness and adhesion were measured. It was shown that novel process occurs, with improved coatings adhesion and excellent coverage of the surface. At 90 V the surface is smoother, and there is possibility for crystallization of the components at prolonged deposition times.

The optimization of the anodization process of Ti substrate for in situ synthesis of hydroxyapatite/titanium oxide composite coatings on titanium substrate was accomplished. The anodization was performed under 30, 60 and 90 V cell voltage, and the morphology of treated surface, as well as linear and surface roughness, were analysed by field emission-scanning electron micro­scopy, atomic force microscopy and roughness tester. It was shown by linear and surface roughness analyses that titanium anodized under 60 V has the high­est roughness, whereas at 90 V the flattening of the surface occurs. As the highest surface roughness results emerged at 60 V, the novel process of com­po­site anHAp/TiO2 coating synthesis, which comprises simultaneous processes of TiO2 formation and HAp deposition, as well as HAp impregnation within TiO2 surface layer, was performed at this voltage. Ti substrate surface was completely covered by composite coating, with no visible cracks. The adhesion quantified according to ASTM D3359-02 standard is considerably improved with respect to the coatings obtained by cathaphoretic processes, with no need of subsequent sintering.

Supercapacitors are one of the most promising devices for energy storage, which can, in the highest extent, bridge the batteries/capacitors energy/power gap. Ruthenium oxide is one of the most powerful, with superior pseudocapacitive properties and high theoretical specific capacitance, depending on its structure. It has widespread application in many fields, one of which is as a coating of dimensionally stable anodes (DSA). Different methods for the synthesis of RuO2 are presented, such as the thermal decomposition of RuCl3, the sol-gel process, the polyol process, the silar method, hydrothermal synthesis, spray pyrolysis, the evaporation-induced self-assembly (EISA) method, electrochemical deposition, chemical deposition from the vapor phase, etc. In recent years, microwave (MW)-assisted procedures were shown to be powerful techniques for the synthesis of a variety of materials, especially metal oxides, through hydrothermal routes. Highly active RuO2 coatings on Ti could be prepared from colloidal suspensions of the oxide synthesized under the rigorous heating conditions induced by microwave irradiation. Intensification of the heating conditions by increased reaction temperatures and pressures produced small particles and increased the surface energy. The most rapid heating conditions generated the smallest high-energy oxide particles, which were able to form compact RuO2 coatings with high electrochemical activity. The coating capacitive performances and the activity for oxygen evolution seemed considerably improved with respect to those of the coating prepared by the traditional thermal decomposition of chloride or usual hydrothermal processing routes. The synthesised material is of highly accessible inner structure, and is an excellent candidate for both low and high power applications.

In-situ synthesis of HAp/TiO2 coating on titanium was performed via anaphoretic deposition of HAp and simultaneous anodization of Ti to produce highly adherent and strengthened composite coating. The prepared coatings were characterized by field emission scanning electron microscopy, X-ray diffraction and electron dispersive spectroscopy. HAp on anodized titanium was prepared at constant voltage of 60 V and deposition time of 45 s, which provided uniform and adherent HAp/TiO2 composite coating on Ti. Since smaller size of HAp crystals within highly porous coating structures is of improved binding ability to various biomolecules, our coating is expected to be of excellent coverage and compactness. The obtained coating can be good candidate for bone implants due to reduced brittleness and improved adhesion.

The medical devices based on titanium and its alloys are widely used in the repair and replacement of a degraded or inhibited func-tion of locomotor system [1]. Ti and its alloys exhibit high mechanical strength, good workability, resistant to corrosion and low cost. Although, they are widely used as orthopedic and dental implants their inability to interact with living tissue will inhibit their biological fixation and osseoin-tegration [2]. Therefore, to improve the hard-tissue compatibility of Ti various sur-face treatments have been developed for the inorganic coating formation [3]. The hyd-roxyapatite (HAp, Ca10(PO4)6(OH)2) with superior osteogenic activity is a competitive approach to make novel coatings for titanium implants applications. HAp is a calcium phosphate very similar to the inorganic part of the human bone and hard tissues both in morphology and compo-sition. Herein, in-situ synthesis of HAp/TiO2 coating on titanium was performed via ana-phoretic deposition of HAp and simulta-neous anodization of Ti to produce highly adherent and strengthened composite coating. It can be seen that morphology of Ti substrate of anHAP/TiO2 coating is of tubular shape, and tube formation occurs mainly due to competing processes of anodization and electrophoretic deposition of HAp. anHAp/TiO2 coating does not need sintering process, and simultaneous Ti anodization and HAp deposition occur, where HAp crystals incorporate in the anodized Ti surface. From the presented results it can be concluded that novel suggested process of in situ simultaneous anHAp/TiO2 deposition with Ti surface anodization gives much better results that cathaphoretic deposition regarding adhesion.

Titanium substrates were electrochemically treated by novel in-situ synthesis method to produce anaphoretic hydroxyapatite/titanium oxide (HAp/TiO2) coating. This synthesis method was performed via anaphoretic deposition of hydroxyapatite and simultaneous anodization of Ti in order to produce highly adherent and strengthened composite coating, where the influence of electric potential, time, electrolyte concentration and pH value of the anodization process on titanium surface roughness and adhesion strength of composite HAp/TiO2 coatings was examined. In situ synthesis was performed in different solutions containing different concentrations of NaOH, HAp and ethanol at different values of time and constant voltage. The effects of anodizing voltage on the morphology and bioactivity of the HAp coating and on the bonding strength between the HAp coating and the anodized substrates were investigated. A modified chemical precipitation method was used to prepare hydroxyapatite powder by the reaction of stoichiometric amount of calcium oxide and phosphoric acid. Prior to novel in situ synthesis of HAp/TiO2 composite coatings, optimization of anodization process of titanium was performed. Anodization was executed under different electric potentials and different distances of counter electrodes from working electrodes, but all experiments had constant quantity of electric charge. Results indicated that highly ordered amorphous TiO2 surface is formed on the Ti substrate after anodic oxidation. Characterization of titanium samples having rectangular contact surfaces of 10×10×0.89 mm included SEM/EDS analyses, X-ray diffraction analyses, AFM surface topography, morphology and roughness analyses and linear measurements of roughness. The prepared coatings were characterized by FE-SEM, XRD and EDS. Adhesion was investigated by ASTM D 3359–97 Test method B. Uniform and adherent HAp/TiO2 composite coating on Ti was obtained. The results of simulated body fluid immersing experiments s

The optimization of the anodization process of Ti substrate for in situ synthesis of hydroxyapatite/titanium oxide composite coatings on titanium substrate was accomplished. The anodization was performed under 30, 60 and 90 V cell voltage, and the morphology of treated surface, as well as linear and surface roughness, were analysed by field emission-scanning electron micro­scopy, atomic force microscopy and roughness tester. It was shown by linear and surface roughness analyses that titanium anodized under 60 V has the high­est roughness, whereas at 90 V the flattening of the surface occurs. As the highest surface roughness results emerged at 60 V, the novel process of com­po­site anHAp/TiO2 coating synthesis, which comprises simultaneous processes of TiO2 formation and HAp deposition, as well as HAp impregnation within TiO2 surface layer, was performed at this voltage. Ti substrate surface was completely covered by composite coating, with no visible cracks. The adhesion quantified according to ASTM D3359-02 standard is considerably improved with respect to the coatings obtained by cathaphoretic processes, with no need of subsequent sintering.

In-situ synthesis of hydroxyapatite/titanium oxide (HAp/TiO2) coating on titanium was performed via anaphoretic deposition of hydroxyapatite (HAp) and simultaneous anodization of Ti to produce highly adherent and strengthened composite coating. The influence of electric potential, time, electrolyte concentration and pH value of the anodization process on titanium surface roughness and anodization of titanium was examined, as well as influence of same process parameters on adhesion strength and compactness of composite HAp/TiO2 coatings was investigated. Prior to novel in situ method of synthesis of hydroxyapatite/titanium oxide composite coatings by simultaneous anodization/anaphoretic electrodeposition described in this manuscript, optimization of anodization process of titanium was performed. Anodization was executed under different electric potentials and different distances of counter electrodes from working electrodes, but all anodization processes had constant quantity of electric charge. Characterization of titanium samples, prepared from grade 6 Ti, and having rectangular contact surfaces of 10×10×0.89 mm included SEM/EDS analyses, X-ray diffraction analyses, AFM surface topography, morphology and roughness analyses and linear measurements of roughness. A chemical precipitation method was used to prepare hydroxyapatite powder by the reaction of calcium oxide (obtained by calcination of CaCO3 for 5 h at 1000 °C in air) and phosphoric acid. A stoichiometric amount of the calcium oxide was stirred in distilled water and phosphoric acid was added drop wise to the suspension in order to obtain hydroxyapatite powder, Ca10(PO4)6(OH)2. Two types of HAp coatings were prepared, in order to compare the adhesion, morphology and consistency of the HAp and composite HAp/TiO2 on Ti, namely cathaphoretic and anaphoretic coatings, respectively [1,2]. The prepared coatings were characterized by field emission scanning electron microscopy, X-ray diffraction and electron disper

In-situ synthesis of HAp/TiO2 coating on titanium was performed via anaphoretic deposition of HAp and simultaneous anodization of Ti to produce highly adherent and strengthened composite coating. The prepared coatings were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and electron dispersive spectroscopy. HAp on anodized titanium was prepared at constant voltage of 60 V and deposition time of 45 s, which provided uniform and adherent HAp/TiO2 composite coating on Ti. Since smaller size of HAp crystals within highly porous coating structures is of improved binding ability to various biomolecules, our coating is expected to be of excellent coverage and compactness. The obtained coating can be good candidate for bone implants due to reduced brittleness and improved adhesion.

In-situ synthesis of HAp/TiO2 coating on titanium was performed via anaphoretic deposition of HAp and simultaneous anodization of Ti to produce highly adherent and strengthened composite coating. The prepared coatings were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and electron dispersive spectroscopy. HAp on anodized titanium was prepared at constant voltage of 60 V and deposition time of 45 s, which provided uniform and adherent HAp/TiO2 composite coating on Ti. Since smaller size of HAp crystals within highly porous coating structures is of improved binding ability to various biomolecules, our coating is expected to be of excellent coverage and compactness. The obtained coating can be good candidate for bone implants due to reduced brittleness and improved adhesion.

Considerable promotion of A’ substituted AA’BO3 perovskite-like structure of rare earth–CoO3 composite supercapacitive performances is reported. The influence of cation substitution in perovskite structure on supercapacitance was also investigated. Spherical, sub-µm-sized, regular spheres of La0.6Sr0.4CoO3 (LSCO) and LaCoO3 (LCO) were synthesized by ultrasonic spray pyrolysis under different temperatures. The synthesis of Co-based oxide, namely La0.6Sr0.4CoO3 (LSCO), was performed within single-step USP procedure. As starting precursors aqueous solutions with 0.10 M concentration of La(NO3)3·6H2O (99.9% rare earth oxide), Sr(NO3)2 (99 %) and Co(NO3)2 (98%) were used for the synthesis of LSCO, and aqueous solutions with 0.10 M concentration of La(NO3)3·6H2O (99.9% rare earth oxide) and Co(NO3)2 (98%) were used for synthesis of LCO. The solution for the LSCO and LCO synthesis were prepared by mixing starting precursor solutions in stoichiometric mole ratios. Synthesis temperatures were adjusted and kept to 600°C and 800°C. LSCO and LCO composites were investigated for their supercapacitive performances in alkaline solution. Microstructure and surface morphology were studied by Scanning Electron Microscopy and X-ray Diffraction measurements. Electrochemical characterization of all LCO and LSCO samples included cyclic voltammetry (CV), galvanostatic charge-discharge (G C/DC) and electrochemical impedance spectroscopy (EIS). The registered capacitance for LSCO reveals the promoting influence of Sr on A’ position in perovskite on capacitance. The EIS analysis showed that Sr catalyzes the redox transition of Co species, with simultaneous proportional increase in capacitive abilities. This intrinsic interactive promotion introduces LSCO composite as unique supercapacitive material. Synthesis temperature plays important role on supercapacitive performances.

Perovskite have emerged as promising materials in newly invented energy storage and conversion devices due to their exceptional thermal stability, electronic structure, ionic conductivity, electron mobility, and redox behaviour [1]. Among perovskite that are suitable as catalyst for electrode in supercapacitors and solid oxide fuel cells, lanthanum strontium cobalt oxides have shown promising catalytic activity and relatively high stability [1]. Also, Co-based lanthanum manganite (LMCO) has been used as cathode material with a high electro-chemical catalytic activity for oxygen reduction[2].Ultrasonic spray pyrolysis (USP) was used to successfully synthesize spherical sub-µm-sized of La0.6Sr0.4CoO3 (LSCO) and Mn and Sr-doped LaCoO3 powders. LSCO should be of wider voltage window than carbonaceous materials, with the possibility to adopt the pseudocapacitive oxide, such as RuO2, not only by simple surface adsorption, but over full or partial incorporation into the oxide structure. Hence, this work aims to investigate supercapacitive potentials of pure LSCO prepared by single step USP and LSCO doped with RuO2. The catalytic activity of Sr and Mn cation substitution in lanthanum cobalt oxide was also investigated. Electrochemical behaviour was investigated by EIS, CV and LSV techniques. The EIS and CV analyses showed that RuO2 catalyzes the redox transition of Co species, with simultaneous proportional increase in pseudocapacitive abilities of RuO2 itself while being hosted by LSCO. The investigated LMCO electrodes by CV and LSV techniques showed excellent catalytic activity for oxygen reduction. Our work indicated that these perovskite shows potential applications in the field of pseudocapacitance electrode materials and is worthy of further investigation.

In this study we report of considerable promotion of supercapacitive performances of ruthenium oxide hosted by perovskite-like structure of rare earth–CoO3 composite and vice versa. Spherical, sub-µm-sized, regular spheres of La0.6Sr0.4CoO3 (LSCO) were synthesized by ultrasonic spray pyrolysis (USP). The sphere surface was subsequently hydrothermally doped by RuO2. LSCO and LSCO/RuO2 composites were investigated for their supercapacitive performances in alkaline solution. Microstructure and surface morphology were studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD). It was found that amorphous Ru species decorate the surface of LSCO spheres, and possibly incorporate partially into a B-site of the LSCO lattice. Electrochemical characterization by cyclic voltammetry (CV) clearly revealed that capacitive performances of LSCO are considerably improved by 20 mass% addition of RuO2. The registered capacitance for LSCO/RuO2 reaches the values of USP-synthesized pure RuO2, which reveals the promoting influence of LSCO on RuO2 pseudocapacitance. This intrinsic interactive promotion introduces the LSCO/RuO2 composite as a unique supercapacitive material.

For the preparation of RuO2 coatings on Ti substrate, the RuO2 was synthesized in acidic aqueous medium by simple one-step low temperature-controlled microwave (MW) irradiation. The physical composition of synthesized solid phase was analysed through particle size distribution (PSD), whereas the coating was investigated for its capacitive response and activity in oxygen evolution reaction (OER). The oxide phase was found highly polydisperse, with overlapped fractions within rather narrow particle size range and clear tendency toward agglomeration. The smallest particles and their best resolved fractions were synthesized at the temperature just above the boiling point of the reaction medium, and quite below the chloride-to-oxide conversion temperature. Consequently, the highest OER activity was registered for RuO2/Ti anodes prepared from this sample, with strong indication of different oxide structure, with respect to the electrodes prepared from samples synthesized at higher temperatures. However, the coatings from high temperature samples have considerably higher capacitance than those synthesized at lower temperatures. These findings can be rather correlated to the MW temperature-dependent oxide structure than to different morphology analysed through PSD.

Hydroxyapatite (HAp) is the most suitable biocompatible material for bone implant coatings. However, its brittleness is a major obstacle, and that is why, recently, research focused on creating composites. In this study, a novel in situ synthesis of HAp coating on titanium was presented. HAp was anaphoretically deposited from alkaline-ethanol suspension in one step process. Morphology of the coating was investigated by optical microscopy, while deposited HAp was characterized using ATR-FTIR. It was concluded that HAp has excellent coverage of the surface without delamination. The obtained coating can be good material for bone implants due to solving HAp brittleness.

Hydroxyapatite (HAp) is the most suitable biocompatible material for bone implant coatings. However, its brittleness is a major obstacle, and that is why, recently, research focused on creating composites. In this study, a novel in situ synthesis of HAp coating on titanium was presented. HAp was anaphoretically deposited from alkaline-ethanol suspension in one step process. Morphology of the coating was investigated by optical microscopy, while deposited HAp was characterized using ATR-FTIR. It was concluded that HAp has excellent coverage of the surface without delamination. The obtained coating can be good material for bone implants due to solving HAp brittleness.

In this study, La0.6Sr0.4CoO3 (LSC) powder and LSC doped with 20 wt.% RuO2 were investigated as anode materials for supercapacitor. Spherical submicron particles of La0.6Sr0.4CoO3 have been synthesized by ultrasonic spray pyrolysis. Morphology of LSC powder was examined by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. Both powders were examined by X-ray diffraction, which indicated that substitution of Ru for Sr and Co in the base strongly increased the electrocatalytic activity of the oxide. Electrochemical characterization results have shown improvement in capacitive characteristics of doped LSC showing that this material is good prerequisite for supercapacitor.

The general idea of using Gr as nanofiller is to minimize the brittleness of HAP and gain an improved composite. Any reinforcement material for HAP should not only significantly effect the mechanical properties, but also must retain HAP’s original biocompatibility. Biomimetic mineralization of Ag/HAP/Gr composite coatings was proved by newly formed apatite in SBF that enhance its corrosion stability. The antibacterial acitivity against Staphylococcus aureus and non- cytotoxicity against healthy peripheral blood mononuclear cells (PBMC) showed that these coatings have potential as bone-tissue implants., Generalna ideja korišćenja Gr kao nanofilera je da se umanji krtost HAP u svrhu dobijanja poboljšanog kompozitnog materijala. Svaki ojačavajući materijal za HAP ne treba samo značajno da utiče na mehaničke karakteristike, već i da zadrži originalnu bioaktivnost HAP-a. Biomimetička mineralizacija Ag/HAP/Gr kompozitnih prevlaka je potrvđena formiranjem novog apatita u SBF-u što unapređuje korozionu stabilnost. Antibakterijska aktivnost protiv Staphylococcus aureus i ne citotoksičnost prema zdravim mononuklearnim perifernim ćelijama krvi su pokazali da ove prevlake imaju potencijala kao implanti koštanog tkiva.

The biocomposite hydroxyapatite/graphene (HAP/Gr) and silver/hydroxyapatite/graphene (Ag/ HAP/Gr) coatings were electrodeposited on titanium substrate using the electrophoretic deposition (EPD) technique to produce bioactive coating with improved mechanical characteristics and corrosion stability in simulated body fluid (SBF). The electrodeposited coatings were characterized by scanning electron microscopy, Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, X-ray photoelectron analysis, nanoindentation test and electrochemical impedance spectroscopy. Both HAP/Gr and Ag/HAP/Gr coatings exhibited reduced surface cracks, better mechanical resistance, enhanced thermal and corrosion stability, as well as bioactivity No antibacterial activity against Staphylococcus aureus and Escherichia coli was verified in the case of HAP/Gr coating, while Ag/HAP/Gr coating exhibited antibacterial activity indicating the high potential for biomedical applications. Both coatings were classified as non-cytotoxic against healthy peripheral blood mononuclear cells (PBMC).

Electrochemical synthesis was employed to prepare a novel hydroxyapatite/graphene (HAP/Gr) composite powder suitable for medical applications as a hard tissue implant (scaffold). The synthesis was performed in a homogeneous dispersion containing Na(2)H(2)EDTA center dot 2H(2)O, NaH2PO4 and CaCl2 with a Ca/EDTA/PO43- concentration ratio of 0.25/0.25/0.15M, along with 0.01 wt% added graphene nanosheets, at a current density of 137 mA cm(-2) and pH value of 9.0. The field emission scanning electron microscopy and transmission electron microscopy observations of the composite HAP/Gr powder indicated that nanosized hydroxyapatite particles were uniformly placed in the graphene overlay. Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction confirmed graphene incorporation in the HAP/Gr powder. The electrochemically prepared HAP/Gr composite powder exhibited slight antibacterial effect against the growth of the bacterial strain Staphylococcus aureus.

The hydroxyapatite/graphene (HAP/Gr) composite was electrodeposited on Ti using the electrophoretic deposition process to obtain uniform bioactive coating with improved mechanical strength and favorable corrosion stability in simulated body fluid (SBF). Incorporation of Gr was verified by Raman spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray photoelectron analysis. The HAP/Gr composite coating exhibited reduced surface cracks, nearly double the hardness, and elastic modulus increased by almost 50% compared to pure HAP coating, as estimated by a nanoindentation test. The bioactive HAP/Gr composite coating provided a newly formed apatite layer in SBF with enhanced corrosion stability, as evidenced by electrochemical impedance spectroscopy. The thermal stability of the HAP/Gr coating was improved in comparison to the pure HAP coating, and the Ca/P ratio was closer to the stoichiometric value. No antibacterial activity against Staphylococcus aureus or Escherichia coli could be verified. The HAP/Gr composite coating was classified as non-cytotoxic when tested against healthy peripheral blood mononuclear cells (PBMC).

We report on thin film deposition by matrix-assisted pulsed laser evaporation of simple hydroxyapatite (HA) or silver (Ag) doped HA combined with the natural biopolymer organosolv lignin (Lig) (Ag:HA-Lig). Solid cryogenic target of aqueous dispersions of Ag:HA-Lig composite and its counterpart without silver (HA-Lig) were prepared for evaporation using a KrF* excimer laser source. The expulsed material was assembled onto TiO2/Ti substrata or silicon wafers and subjected to physical-chemical investigations. Smooth, uniform films adherent to substratum were observed. The chemical analyses confirmed the presence of the HA components, but also evidenced traces of Ag and Lig. Deposited HA was Ca deficient, which is indicative of a film with increased solubility. Recorded X-ray Diffraction patterns were characteristic for amorphous films. Lig presence in thin films was undoubtedly proved by both X-ray Photoelectron and Fourier Transform Infra-Red Spectroscopy analyses. The microbiological evaluation showed that the newly assembled surfaces exhibited an inhibitory activity both on the initial steps of biofilm forming, and on mature bacterial and fungal biofilm development. The intensity of the antibiofilm activity was positively influenced by the presence of the Lig and/or Ag, in the case of Staphylococcus aureus, Pseudomonas aeruginosa and Candida famata biofilms. The obtained surfaces exhibited a low cytotoxicity toward human mesenchymal stem cells, being therefore promising candidates for fabricating implantable biomaterials with increased biocompatibility and resistance to microbial colonization and further biofilm development.

Electrochemical synthesis was employed to prepare a novel hydroxyapatite/graphene (HAP/Gr) composite powder suitable for medical applications as a hard tissue implant (scaffold). The synthesis was performed in a homogeneous dispersion containing Na(2)H(2)EDTA center dot 2H(2)O, NaH2PO4 and CaCl2 with a Ca/EDTA/PO43- concentration ratio of 0.25/0.25/0.15M, along with 0.01 wt% added graphene nanosheets, at a current density of 137 mA cm(-2) and pH value of 9.0. The field emission scanning electron microscopy and transmission electron microscopy observations of the composite HAP/Gr powder indicated that nanosized hydroxyapatite particles were uniformly placed in the graphene overlay. Raman spectroscopy, Fourier transform infrared spectroscopy and X-ray diffraction confirmed graphene incorporation in the HAP/Gr powder. The electrochemically prepared HAP/Gr composite powder exhibited slight antibacterial effect against the growth of the bacterial strain Staphylococcus aureus.