Anodic Technique Research Articles

Producing Activated Biochar from the Reuse of Discarded Coffee Grounds with Enhanced Adsorptive Features Explored Towards the Stripping Voltammetric Sensing of Copper (II)

AbstractThis work aims to allocate coffee grounds waste to the production of biochar from pyrolysis under different temperatures (350 °C and 500 °C), to add value to it. The resulting materials were characterized by immediate, elemental, thermogravimetric analysis, SEM, FT‐IR, XRD and Raman spectroscopy. Additionally, the need to activate the biochar produced for the desired use was evaluated. The obtained biochars were applied in electroanalysis in the manufacture of modified carbon paste electrodes. This choice was made due to the possibility of reaching a high sensitivity towards the determination of Cu2+ ions. The differential pulse adsorptive anodic stripping voltammetry technique was applied to perform the Cu2+ determination and, in this case, several parameters were optimized, including biochar’ percentage, pH of pre‐accumulation step and reduction/stripping step, pre‐accumulation time, potential and time of reduction of adsorbed‐Cu2+. From this, the proposed modified electrode showed a linear voltammetric response towards Cu2+ in the range of 66.1 to 3997.3 ppb, with a limit of detection of 31.8 ppb, in addition to having been satisfactorily applied in the analysis of water samples (recoveries close to 100 %). Thus, demonstrating the potential for reuse of discarded coffee grounds for the preparation of activated biochar with outstanding electrochemical performance.

Dynamic behaviors of bridge with corroded RC piers under barge collisions

Reinforced concrete (RC) bridge piers located in navigable waterways are susceptible to chloride-induced corrosion, which may cause severe damage or even entire collapse of bridge under potential barge collisions. The present study aims to examine the failure patterns and dynamic responses of typical simply supported girder bridge with corroded RC piers under barge collisions. Firstly, nine RC column specimens with three designed corrosion degrees and two corrosion strategies were prepared using the impressed anodic current technique. Secondly, the drop hammer impact and axial compression tests were successively performed to examine the residual axial load bearing capacities of both unimpacted and impacted specimens. Furthermore, by comprehensively considering the effects of corrosion-induced deteriorations on the effective cross-sectional area and yield strength of reinforcements, concrete strength, as well as the rebar-concrete bond-slip relationship, the refined finite element (FE) models of specimens were established and validated. Finally, the dynamic behaviors of a prototype simply supported girder bridge with corroded RC piers under barge collisions at different service lives, i.e., 0–60 years, were numerically assessed. It indicates that: (i) under drop hammer impact, six specimens all exhibit global flexure failure, and relatively severe concrete cracking and spalling occur in the specimens with 15 % designed corrosion degree; (ii) the axial load bearing capacities of specimens with 5 % and 15 % designed corrosion degrees are reduced by 15.46 % and 34.86 % compared to the unimpacted non-corroded specimen, and 11.29 % and 43.30 % compared to the impacted non-corroded specimen; (iii) the transverse impact resulted in 25.93 %, 22.27 % and 35.53 % reductions in axial load bearing capacities for 0 %, 5 % and 15 % designed corrosion degree, respectively; (iv) for the prototype barge-bridge collision scenario, the failure patterns vary from minor bending cracks to remarkable flexural failure as the service live increases from 0 to 60 years. The corrosion-induced degradations of bridge performance should be concerned for the vessel collision-resistant design of bridge.

Preparation, optical properties, room temperature ferromagnetism, and mechanism of ordered nanotube-like tantalum oxide films

Physical property changes caused by defects have recently attracted significant attention due to their potential applications in sensors, spintronic devices, and multifunctional memory. Due to their numerous surface defects, this study fabricated ordered Ta2O5 nanotube (NT) thin films on Ta foil through an anodization technique. Then, the oxygen bubble model was applied to explain the formation of NTs from the perspective of lattice orientation. Furthermore, this study investigated influence of anodization duration and annealing treatment on the crystal structure, optical properties, and magnetic behavior. Notably, room-temperature ferromagnetism was observed in the as-prepared Ta2O5 NTs for the first time. After annealing in an argon atmosphere, the band gap of the sample decreased, accompanied by an increase in ferromagnetism. The underlying mechanism for this phenomenon was elucidated using a hydrogen-like impurity model. Consequently, this study on the magnetism of Ta2O5 NTs holds excellent potential for expanding their application in spin electronic devices.

Submerged nanoporous anodized alumina structure for solar-powered desalination.

Development of nanoporous structures utilizing a single step of anodization technique is well recognized as a cost-effective and straightforward approach for several applications. In the current work, anodized alumina was developed with nanoporous structure by utilizing oxalic acid as an electrolyte with a continuous voltage of 40 V. The formed nanoporous structure was subjected to desalination application because of its high absorbance of broadband solar spectrum energy. The desalination setup consists of two solar stills namely conventional and modified. The developed structure is placed in the modified still to examine its performance. It was observed that the structure distributing heat to surrounding water by absorbing photon energy from the sun through the nanopores and giving an efficient pathway to the water vapours for developing effective desalination. The nanoporous structure having ~ 45 nm average diameter. Furthermore, the band gap energy of nanoporous structure was found to be ~ 2.5 eV (absorption spectrum fitting) and ~ 2.8 eV (Tauc plot). The nanoporous structure possess the visible light spectra in solar region which helps the band gaps of nanoporous structure to provide an additional supply of energy for generating more water to evaporate. Moreover, the Urbach energy of the structure is 0.5 eV which reveals less defects in the modified still. The overall distillate yield of modified still was increased to 21% in contrast to conventional. Water quality analysis was also carried out before and after the desalination experiments, and the results were within acceptable limits set by World Health Organization (WHO).

Plasmonic Bound States in the Continuum Metasurface-Semiconductor-Metal Architecture Enables Efficient Hot-Electron-Based Photodetector.

Plasmonic hot-electron-based photodetectors (HEB-PDs) have received widespread attention for their ability to realize effective carrier collection under sub-bandgap illumination. However, due to the low hot electron emission probability, most of the existing HEB-PDs exhibit poor responsivity, which significantly restricts their practical applications. Here, by employing the binary-pore anodic alumina oxide template technique, we proposed a compact plasmonic bound state in continuum metasurface-semiconductor-metal-based (BIC M-S-M) HEB-PD. The symmetry-protected BIC can manipulate a strong gap surface plasmon in the stacked M-S-M structure, which effectively enhances light-matter interactions and improves the photoresponse of the integrated device. Notably, the optimal M-S-M HEB-PD with near-unit absorption (∼90%) around 800 nm delivers a responsivity of 5.18 A/W and an IPCE of 824.23% under 780 nm normal incidence (1 V external bias). Moreover, the ultrathin feature of BIC M-S-M (∼150 nm) on the flexible substrate demonstrates excellent stability under a wide range of illumination angles from -40° to 40° and at the curvature surface from 0.05 to 0.13 mm-1. The proposed plasmonic BIC strategy is very promising for many other hot-electron-related fields, such as photocatalysis, biosensing, imaging, and so on.

Solar Light-Induced Photoelectrochemical H2 Generation Over Hierarchical TiO2 Nanotube Arrays Decorated with CdS Nanoparticles

The process of converting solar energy into chemical energy through photoelectrochemical (PEC) water splitting holds significant promise for hydrogen and oxygen gas production. In the current study, we have demonstrated the feasibility of designing a high-performance heterojunction photoanode in a scalable manner. This photoanode sensitizes visible light active CdS onto hierarchical TiO2 nanotubes (TNT), thereby enhancing H2 generation. To achieve this, we initially employed an electrochemical anodization technique to fabricate vertically aligned self-organized TNT on a titanium (Ti) substrate. Subsequently, we designed a hierarchical structure for TNT by uniformly decorating them with TiO2 nanoparticles (NPs), thus amplifying the available surface area. By employing the sequential ionic layer adsorption and reaction (SILAR) technique, we establish visible light sensitization. The resulting decorated hierarchical TNT photoanode demonstrates an enhanced photocurrent of 2.60 mA cm−2 under AM 1.5 G simulated solar light, surpassing the performance of hierarchical TNT, and most importantly classic CdS/TNT structures by 17-fold, and 1.6-fold, respectively. Moreover, the developed photoanodes achieved photoconversion efficiency with an applied bias (ABPE) of 2.48%. Thus, this work shows that a hierarchical scaffold can be exploited to achieve enhanced activity in photoelectrochemical H2 generation.

Photoelectrode FTO/ Anodized TiO2 Production and Characterization for Methylene Blue Affected Photoelectrochemical Decomposition

Background: The production of thin film TiO2 nanostructured systems for electrocatalytic, photocatalytic, and photoelectrocatalytic applications has been an essential topic in recent years. Due to the light-sensitive effect of TiO2, it can be produced by various methods and used as a photoelectrode to remove dye. Using magnetron sputtering, Ti thin films can be deposited on different substrates and converted into transparent TiO2 structures by electrochemical anodization. Methods: In this study, the thin Ti film was produced using a magnetic spraying technique on the FTO substrate, and then an anodic TiO2 structure was obtained by the anodization technique. TiO2 films produced by the anodizing technique were used as a photoelectrode for the degradation of MB. The reactor contained 400 mL of 20 mg/L MB solution at 20 °C. The produced photoelectrode was characterized by the SEM/EDS, FTIR, XRD, and UV-Vis Spectrophotometer analyses. Results: The EDS analysis confirmed the presence of titanium and oxygen in the FTO/ Anodized TiO2 photoelectrode. The XRD results showed that all the peaks of the produced FTO/ Anodic TiO2 were associated with the anatase phase of TiO2. According to the FTIR spectroscopy, the functional groups of the anodized TiO2 were obtained for the FTO/ Anodized TiO2. The electrocatalytic, photocatalytic, and photoelectrocatalytic degradation experiments were performed with the degradation of the dye solution of MB on the FTO/ Anodic TiO2 photoelectrode, and the rates of dye degradation were determined as 17.12%, 64.67%, and 82.12%, respectively. Conclusion: This study showed that the methylene blue dye of FTO/ Anodic TiO2 is a suitable photoelectrode for electrocatalytic, photocatalytic, and photoelectrocatalytic degradation.

Improved Fog Collection on a Hybrid Surface with Acylated Cellulose Coating.

Fog collection serves as an efficient method to alleviate water scarcity in foggy, water-stressed regions. Recent research has focused on constructing a hybrid surface to enhance fog collection efficiency, with one approach being the prevention of liquid film formation at hydrophilic sites. Inspired by the desert beetle, a coating (10-MCC) made by partially acylating microcrystalline cellulose (MCC) exhibits hydrophilic sites alongside a hydrophobic skeleton enabling rapid droplet capture despite its overall hydrophobicity. The captured droplets quickly coalesce into a large droplet driven by the wetting gradient created by the hydrophobic backbone and hydrophilic sites. To achieve greater fog collection efficiency, a hydrophobic-superhydrophobic hybrid surface is formed by combining a coating of 10-MCC with a superhydrophobic surface. The construction of superhydrophobic surfaces typically involves creating a rough surface with a distinctive structure produced by the anodization technique and modifying it with stearic acid. The superhydrophobic surface exhibits excellent corrosion resistance and mechanical stability. Moreover, the hybrid surface shows high efficiency in fog collection, with a tested maximum efficiency of approximately 1.5092 g/cm2/h, 1.77 times that of the original Al sheets. The results demonstrate a remarkable enhancement in fog collection capacity. Furthermore, this work serves as an inspiration for the low-cost and innovative design of engineered surfaces for efficient fog collection.

Electroosmotic flow in soft clay and measures to promote movement under direct current electric field.

Electroosmosis has been proposed as a technique to reduce moisture and thus increase the stability of soft clay. However, its high energy consumption and uneven reinforcement effect has limited its popularization and application in practical engineering. This paper presents the results of some electrokinetic tests performed on clayey specimens with different electrification time and anode boundary conditions. The results indicate that the timing of the formation of electroosmotic flow (EF) by the water originally contained in different soil cross sections, from the anode to the cathode, varies. The measuring soil cross section nearest the anode first reached the limiting water content of 22%±3% and electroosmosis had to be stopped. Water injection into the anode during electroosmosis enhanced further drainage of other four measuring soil cross sections until the second soil cross section from the anode reached the limiting water content of 30%±2%. Electroosmosis with water injection into the anode technique provides more uniform reinforcement, increasing EF, and environmental protection. The experimental results highlighted the relevant and expected contribution of water injection into the anode on the effectiveness of the electroosmotic treatment as a soft clay improvement technique.

Enhanced bonding of polyphenylene sulfide-aluminum alloy composites using combined mild and hard anodizing techniques

High-strength direct joining between polymers and Al has attracted considerable attention, particularly for reducing the weight device. In this study, porous anodic alumina (PAA) films were fabricated on a commercial 6063 Al alloy using with mild and hard anodizing with varying durations, followed by etching. Subsequently, polyphenylene sulfide (PPS) was directly joined with Al through injection molding. The correlations between the interface bond strength of PPS-Al joints and the Al oxidation duration were systematically investigated. The porosity, diameter of nanopore, and wettability of anodic aluminum oxide (AAO) film surface significantly influenced the bonding strength of PPS-Al composite structure. The porosity increased with an etching duration, increasing the bonding strength. However, excessive porosity (>54 %) weaken the films and reduced their bonding strengths. When the durations of mild anodizing (MA), hard anodizing (HA), and etching treatment were set to 30, 30, and 60 min, respectively, the maximum bonding strength reached 25.2 MPa, approximately 77 % of the base-material shear strength. Scanning electron microscopy revealed nanopillars with two different top sizes (approximately 80 and 110–130 nm) on the surface of injection-molded PPS, which were attributed to the different anodizing preparation voltage. These findings are generally significant for the realization for high-strength direct-bonded polymer-Al joints.

Cathodic luminol electrochemiluminescence on TiO2 nanotube array

This study introduces a novel fabrication of screen-printed electrode of hierarchical thin layers of TiO2 nanotube arrays (TNA) and its preliminary investigation for cathodic electrochemiluminescence (ECL) of luminol. The TNA growth on titanium foil by anodization technique was studied under various anodization times and counter electrodes (Pt wire and stainless-steel plate). Characterization using FTIR, UV-VIS DRS, and XRD revealed the increase of TiO2 formation at longer anodization times. The TNA synthesized with a stainless-steel counter electrode (TNA-SS) for 2000 s exhibited better nanotube growth and a higher electrochemical active surface area compared to the one using Pt counter electrode (TNA-Pt). The SEM characterization verified the nanotube morphology of TNA-SS with an average pore diameter of 50.46 nm and a tube length of ∼1100 nm. Notably, when TNA applied as the working electrode for the ECL of luminol, a reduction peak at −0.8 V accompanied by a clear ECL signal were observed, reaching an optimum intensity at 15 μM luminol. A comparative analysis between TNA-SS and TNA-Pt revealed the same trend of ECL signals with a significantly higher ECL intensity of TNA-SS than that of TNA-Pt. The ECL intensity of TNA-SS 2000s was also higher than TNA-SS 300s, confirming the importance of TNA surface area to the ECL activity. Nevertheless, the synthesized SPE-TNA shows great prospect to be applied in electroanalytical and sensing fields, offering opportunities for the development of electrochemiluminescence technologies.

1‐2: High Performance of InSnO Thin‐Film Transistors Enabled by Anodization Techniques

1‐2: High Performance of InSnO Thin‐Film Transistors Enabled by Anodization Techniques

Influence of electrical polarization on thrombogenicity of titania nanotubes

AbstractThe development of hemocompatible biomaterials with antithrombogenic surface coatings remains a challenge in cardiovascular applications. There is interest in negatively charged surfaces that inhibit thrombus formation through electrostatic repulsion between the biomaterial surface and negatively charged platelets. Hence, the present study investigated the influence of electrical polarization on the thrombogenicity of titania nanotubes (TNT), which are promising candidates for inhibiting thrombogenicity via surface modification. TNTs were formed on commercially pure titanium plate by the electrochemical anodization technique using platinum as a counter electrode at 60 V for 24 h with two kinds of electrolytes (hydrofluoric acid diluted with dimethyl sulfoxide [D‐TNT] or ethylene glycol [E‐TNT]) followed by an annealing at 540°C for 3 h in air. Both TNTs were mixture of anatase and rutile, and the D‐TNT had a diameter of 108.76 ± 2.55 nm and the E‐TNT, 53.833 ± 2.42 nm. The TNTs were electrically polarized at 100 V of DC field and 400°C for 1 h. Water contact angle measurements showed that the non‐polarized (0‐) TNT surface was hydrophilic whereas the positively (P‐) or negatively (N‐) polarized TNT surfaces showed high‐hydrophilicity. Antithrombogenicity was evaluated using the thrombus coverage area ratio (TCAR) after soaking the TNTs in bovine whole blood. The TCARs for 0‐polarized E‐ and D‐TNTs were 5.30 ± 4.34% and 36.3 ± 5.8% and for P‐polarized E‐TNT and D‐TNT were 1.50 ± 0.77% and 2.76 ± 1.07%, whereas no thrombus formation (0 ± 0%) for N‐polarized E‐TNT and very few thrombus formation (0.12 ± 0.22%) for N‐polarized D‐TNT. The electrostatic repulsion between the N‐polarized E‐TNTs and platelets completely inhibits thrombus formation, which cannot be achieved by the nanomorphology and high‐hydrophilicity of other TNTs. Hence, N‐TNTs formed by electrical polarization are potential candidates for cardiovascular devices, such as artificial heart valves with long‐term hemocompatibility.

Anodization as a scalable nanofabrication method to engineer mechanobactericidal nanostructures on complex geometries.

Bacterial contamination of implant surfaces is one of the primary causes of their failure, and this threat has been further exacerbated due to the emergence of drug-resistant bacteria. Nanostructured mechanobactericidal surfaces that neutralize bacteria via biophysical forces instead of traditional biochemical routes have emerged as a potential remedy against this issue. Here, we report on the bactericidal activity of titania nanotubes (TNTs) prepared by anodization, a well-established and scalable method. We investigate the differences in bacterial behavior between three different topographies and demonstrate the applicability of this technique on complex three-dimensional (3D) geometries. It was found that the metabolic activity of bacteria on such surfaces was lower, indicative of disturbed intracellular processes. The differences in deformations of the cell wall of Gram-negative and positive bacteria were investigated from electron micrographs Finally, nanoindentation experiments show that the nanotubular topography was durable enough against forces typically experienced in daily life and had minimal deformation under forces exerted by bacteria. Our observations highlight the potential of the anodization technique for fabricating mechanobactericidal surfaces for implants, devices, surgical instruments, and other surfaces in a healthcare setting in a cheap, scalable way.

Electroplating wastewater treatment by electro-oxidation using synthesized new electrode: Experimental, optimization, kinetics, and cost analysis

The present work studied electroplating wastewater treatment by the electro-oxidation (EO) method through a new Ti/TiO2-GO-SnO2 electrode in a once-through continuous mode. The Ti/TiO2-GO-SnO2 electrode was synthesized using an anodic oxidation technique and characterized by electrochemical characterizaftion. Response Surface Methodology (RSM) employing a Box-Behnken Design (BBD) model was utilized to optimize pH (3−7), current density (j = 16.72–50.16 mA/cm2), and time (t = 30–130 min) for removal of electroplating effluents and energy consumption. At the optimum condition, the values of the responses R1 (% Cr(VI) removal), R2 (% Zn removal), R3 (% COD removal), and R4 (energy consumption) were found to be 97.55%, 95.66%, 87.32%, and 14.97 kWh/m3, respectively. The effect of reactive species scavengers on removing electroplating effluents has been studied. The kinetics and cost analysis were also carried out under optimal conditions. Once-through continuous experiments were carried out at different flow rates to determine the viability of the process at industrial or pilot scale applications. The synthesized electrode proved highly reusable, maintaining durability even after sixty cycles of usage. Toxicity analysis showed that EO has the potential to detoxify electroplating effluents. The observed results confirm that the EO with Ti/TiO2-GO-SnO2 electrode is low-cost and effective for removing electroplating effluents.

Dopamine-mediated copper-loaded ZnTiO3 antimicrobial coating with immunomodulatory properties effectively enhances vascularised osteogenesis on titanium implants

In this study, zinc (Zn) with osteogenic activity and copper (Cu) with angiogenic activity were simultaneously introduced into titanium dioxide nanotubes (TN) by means of anodic oxidation technique, hydrothermal reaction and dopamine (PDA) polymerisation effect (ZnTN-PDA-Cu). The ZnTN-PDA-Cu coating had favourable mechanical, hydrophilic, corrosion-resistant, and bioactive characteristics, according to the results. Zn2+ and Cu2+ could be continuously released from the coating and was pH-responsive. In addition, ZnTN-PDA-Cu showed good antibacterial properties against E. coli and S. aureus. Cellular assays revealed that RAW264.7 (immune), HUVEC (angiogenic) and MC3T3-E1 (osteogenic) exhibited good adhesion and proliferation activities on the ZnTN-PDA-Cu coated Ti. The expression of anti-inflammatory markers, angiogenic markers and osteogenic markers was significantly up-regulated in ZnTN-PDA-Cu coatings at both the gene level and protein level. ZnTN-PDA-Cu also demonstrated the capacity to stimulate RAW264.7 towards M2 polarisation and HUVEC tube formation. In addition, it demonstrated the capacity to stimulate MC3T3-E1 towards osteogenic differentiation. In summary, the ZnTN-PDA-Cu coating had better antibacterial, anti-inflammatory, angiogenic and osteoinductive properties. The multifunctional coatings prepared in this study provide a promising new strategy and experimental basis for the design of antibacterial titanium surfaces with immunomodulatory functions.

Simultaneous square wave voltammetric determination of two anti-inflammatory drugs using a bare carbon paste electrode

Background Diclofenac (DIC) is a nonsteroidal anti-inflammatory drug (NSAID) that is more potent than indomethacin. There is an extended-release form of this drug available for long-term treatment. Diflunisal (DIF) is a NSAID with less anticoagulant activity than aspirin. It is more potent than aspirin and is not converted to salicylic acid in vivo. Objectives A simple, direct, and sensitive method for the simultaneous determination of two types of NSAIDs, namely, diclofenac ‘DIC’ and diflunisal ‘DIF’ by square wave adsorptive anodic stripping voltammetry and applied at the same time in synthetic and pharmaceutical samples. Materials and methods In this method, both cited ingredients were oxidized by a bare carbon paste electrode (CPE) forming two well-separated peaks at the potential of 0.65 and 0.85 V, respectively, in 0.04 M universal buffer solution at pH 5 with 100 mV/s scan rate by square wave adsorptive anodic stripping voltammetry technique with an Autolab system of potentiostat/galvanostat. Results and conclusion The prepared sensor showed good linear regression curves over the concentration ranges of 1–6 and 5–25 μg/ml for DIC and DIF, respectively, while the detection limit ‘LOD’ and quantification limit ‘LOQ’ and were 0.204 and 0.68 μg/ml for DIC and 1.366 and 4.553 μg/ml for DIF, in turn. The cited sensor was applied with accurate and precise results for determining DIC and DIF at the same time in synthetic and pharmaceutical samples and gave close results in comparison with the official method, specifically by UV-high performance liquid chromatography.

Emerging Frontiers in Surface Modification: A Critical Investigation of Advanced Anodization Technique for Biomedical Application

Titanium anodizing or titanium oxide coating process has emerged globally nowadays owing to the properties of corrosion resistance, nontoxic & nonreactive nature, improve aesthetically, enhanced fatigue strength, increased osseointegration, exhibits natural biocompatibility, helps in part identification, reduced wear & tear, etc. Titanium anodizing is popular for various applications including aerospace, medical implants, automotive, sports equipment, dental, jewelry, etc. In the present investigation, 08 cylindrical samples of PureTitanium, Grade-4 material (7 for color anodizing and 1 for Type II gray color anodizing) were prepared. After that, samples were thoroughly processed & anodized by using distinct voltage as well as by using an optimum combination of parameters. The constant voltage was used during the anodizing process to achieve a consistent uniform layer thickness. Thereafter, coating thickness was measured on lowest and highest voltage samples, to know the variation of oxide layer formation. Chemical analysis was also performed to know the changes in elemental composition before and after anodizing, whether it comply the standard or not. Finally, all the samples were analyzed for fingerprint issues in case of biomedical applications.

Effect of Voltage on Gas Sensor Performance of Anodization Synthesized TiO2 Nanotubes Arrays

Serious gases have been highly related to being prejudiced against human life within the environment. The evolution of a trustworthy gas sensor with an elevated response is of major importance for detecting various hazardous gases. Titanium dioxide (TiO2) nanotubes (TNTs) are favorable candidates with considerable potential and stellar performance in gas sensor applications. In this work, we have studied the effect of voltage on preparing TiO2 nanotubular arrays via the anodization technique for gas sensor applications. A simple electrochemical anodization approach was used to synthesize titanium dioxide nanotubes. Diverse techniques of characterization were used to evaluate TNTs. The results gained from field emission scanning electron microscopy (FESEM), energy dispersion spectroscopy (EDS), and X-ray diffraction (XRD) indicate that TiO2 was formed. Gas sensors were created, and the gas detection characteristics were directed towards hydrogen sulfide (H2S), which is not a healthy gas. The sensor made from these nanotubes responds well to this gas at different temperatures and has high sensitivity. The H2S-detecting characteristics were evaluated at values ranging from room temperature up to 300 oC. Results show that the gas sensor TNTs that was prepared at 30 volt for H2S gas sensing has the highest sensitivity and shortest response time at room temperature.

Surface engineering of zirconium with chitosan PEDOT for enhanced bioactivity and corrosion behavior

Bio-synthetic polymer incorporated metallic biomaterials and their development acts vivid in orthopedic applications. Zirconium is an evolving implant material in the field of orthopedics. In the present work, Zirconia nanotubes (ZNTs) were fabricated by electrochemical anodization technique. Combining bio-synthetic polymer with zirconia nanotubes could improve the properties of zirconium for load bearing applications. Therefore, Chitosan-PEDOT (ChP) composite was coated on the fabricated ZNTs through dip-coating method. The surface characterization studies were carried out by HR-SEM, ATR-FTIR, XRD and XPS analysis to confirm the formation of ZNTs and ChP coated ZNTs (ChP-ZNTs). The corrosion behavior of bare, ZNTs and ChP-ZNTs were evaluated using Electrochemical Impedance Spectroscopy (EIS), Potentiodynamic polarization studies and Scanning Electrochemical Microscopy (SECM) shows that ChP-ZNTs exhibits superior corrosion inhibition. The In-vitro biomineralization of ChP-ZNTs was performed in Hanks’ solution for 7-days. From the MTT assay, the cell viability and proliferation rate of ChP-ZNTs show better viable percentage in comparison with ZNT and bare sample. Therefore, the fabricated ChP-ZNTs exhibit better corrosion resistance and biocompatibility for orthopedic application.