Surface Elemental Composition Research Articles

Smart Zinc-Based Coatings with Chitosan–Alginate Nanocontainers Loaded with ZnO and Caffeine for Corrosion Protection of Mild Steel

The development of environmentally friendly materials is a subject of increasing interest in corrosion protection research. The objective of the present investigation is to propose the preparation procedure of chitosan–alginate (CHI/ALG) nanocontainers loaded with zinc oxide (ZnO) nanoparticles or combining ZnO nanoparticles with corrosion inhibitor caffeine (CAF), both suitable for incorporation into the matrix of ordinary zinc coatings on mild steel substrates. The nanocontainers were synthesized through spontaneous polysaccharide complexation in the presence of ZnO nanoparticles and CAF using a cross-linking agent, namely tripolyphosphate (TPP). Dynamic light scattering and laser Doppler velocimetry measurements are used for evaluation of the size distribution and zeta potentials of the nanocontainers, both loaded or unloaded with CAF. Using UV-spectroscopy, entrapment efficiency and release amounts of CAF are quantitatively evaluated. The nanocontainers thus obtained were incorporated into the matrices of ordinary zinc coatings via co-electrodeposition with zinc from zinc sulfate solution, aiming to improve the corrosion protection of steel in corrosive environments containing chloride ions. The surface morphology and elemental composition of the electrodeposited hybrid coatings before and after treating in the model corrosive medium of 3.5% NaCl is studied by scanning electron microscopy (SEM). The cyclic voltammetry method (CVA) is applied to characterize the cathodic (electrodeposition) and anodic (dissolution) processes. The protective characteristics of the hybrid coatings are investigated by application of potentiodynamic polarization (PDP) curves and polarization resistance (Rp) measurements after a time interval of 40 days. The obtained results indicate that both hybrid coating types could prolong the life time of mild steel in aggressive Cl− ion-containing solution, combining the protection effect of sacrificial zinc with barrier (ZnO) and active (CAF) protective effects.

Effect of mechanical instrumentation on titanium implant surface properties.

To assess the impact of mechanical decontamination using rotary brushes on the surface topography, elemental composition, roughness, and wettability of titanium implant surfaces. Four commercially available rotary brushes were used: Labrida BioClean Brush® (LB), i-Brush1 (IB), NiTiBrush Nano (NiTiB), and Peri-implantitis Brush (PIB). Seventy-five titanium discs with sandblasted, large-grit, acid-etched (SLA) surfaces were randomly assigned to five groups (n = 15): LB, IB, NiTiB, PIB, and a control group. Each disc was treated for 60 seconds with the respective rotary brush according to the manufacturer's instructions. Surface morphology was analysed using Scanning Electron Microscopy (SEM), surface elemental composition with Energy Dispersive X-ray (EDX), surface roughness via optical profilometry, and wettability with a droplet shape analyser. SEI analysis revealed morphological changes, including scratches, flattening, and loose titanium particles in the IB, PIB, and NiTiB groups, whereas the LB group preserved the original surface morphology. SEM-EDX analysis showed that LB, PIB, and NiTiB groups closely match the control elemental composition. However, IB groups showed significantly different composition. Surface roughness values in the IB, PIB, and NiTiB groups differed significantly from the control (p < 0.05), whereas the LB group had comparable roughness values (p > 0.05). Contact angle measurements indicated enhanced wettability in IB, PIB, and NiTiB groups (p < 0.05), while the LB group exhibited values comparable to the control (p > 0.05). Mechanical decontamination of implant surfaces utilising rotary brushes can alter implant surface properties.

Empirical Optimization of Biomass-Derived Hard Carbon Anode for Efficient Sodium Storage

Hard carbon is widely recognized as the most promising anode material for sodium-ion batteries (SIBs). Hard carbon is a non-graphitizable carbon characterized by a turbostratic structure with disordered stacking of carbon layers, each consisting of a few nanometer-sized graphene layers. It remains difficult to graphitize even at temperatures above 2500°C. This unique structure, combined with its low cost, high electrical conductivity, low working voltage, and high capacity, allows hard carbon to achieve exceptional sodium ion storage performance. These characteristics make it the most commercially viable anode material. Recent research has also actively explored the use of biomass instead of high-cost inorganic materials, to reduce production costs, minimize pollution from biomass incineration, and reduce the significant amounts of biological waste produced annually. This study investigates the performance of hard carbon anodes derived from lignin, with commercial graphite serving as a control. X-ray diffraction (XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS) were utilized to analyze their crystallographic structures, microstructures, and surface elemental compositions. Electrochemical performance was evaluated using electrolytes consisting of 1M NaPF6 in EC/DEC (1:1 v/v) with 5 wt% FEC and 1M NaPF6 in DEGDME. By comparing the electrochemical characteristics of hard carbon and graphite under different electrolyte conditions, this study demonstrates the potential of hard carbon as a promising anode material for sodium-ion battery applications.

Modulating Mn-doped NiO nanoparticles: structural, optical, and electrical property tailoring for enhanced hole transport layers.

Mn-doped NiO nanoparticles (NPs), denoted as Ni1-x Mn x O with x values of 0.00, 0.02, 0.04, 0.06, and 0.08, were synthesized using a chemical precipitation process. These NPs were comprehensively analyzed for their structural, optical, and electrical properties, along with their surface morphology and elemental composition. X-ray Diffraction (XRD) confirmed the single-phase cubic crystal structure and revealed a reduction in crystallite size from 15.26 nm to 10.38 nm as Mn doping increased. Field Emission Scanning Electron microscopy (FE-SEM) determined the average particle sizes ranging from 26.03 nm to 23.30 nm. The optical properties, assessed by UV-visible spectroscopy (UV-vis), revealed a widening of the bandgap from 3.49 eV to 4.10 eV with increasing Mn doping, suggesting tunable optical characteristics. X-ray Photoelectron Spectroscopy (XPS) confirmed the presence of nickel (Ni), oxygen (O), and manganese (Mn) within the NPs. The highest mobility, 1.31 ± 0.03 × 103 cm2 V-1 s-1, was observed in the 6 wt% Mn-doped NiO NPs thin film, as determined by Hall measurements. To assess their practical utility, SCAPS-1D simulation was employed, demonstrating the potential of Mn-doped NiO NPs as a hole transport layer (HTL) in perovskite solar cells (PSCs). The enhanced electrical and optical properties, combined with structural tunability, highlight Mn-doped NiO as a promising material for advanced optoelectronic applications. This study provides valuable insights into the development of efficient and stable solar cells, offering a pathway to optimize material design for improved performance in photovoltaic applications.

Adsorption of Copper and Chromium Mixed Solution on N-Doped Biomass-Activated Carbon

N-doped biomass activated carbon was prepared by direct ultrasonic method and redox method. Scanning electron microscopy, energy-dispersive spectroscopy, Brunnauer-Emmett-Teller, X-ray photoelectron spectroscopy, Zeta potential test, and other characterization methods were used to observe the pore structure, surface functional groups, elemental composition and distribution, and surface charged properties of the two samples. The adsorption experiment of Cu(II)/Cr(VI) mixed solution of two samples was carried out, and the influence of pH value, temperature, and concentration on material properties was explored. The results show that the equilibrium time, adsorption rate, and adsorption capacity of Cu(II)/Cr(VI) mixed solution are shorter, faster, and three times larger compared with the adsorption of single Cu(II) solution. The co-adsorption of Cu(ii) and Cr(vi) was observed. The adsorption capacity of Cr(vi) is not affected by the properties of the materials themselves, but increases with the increase of the initial concentration of Cu(II). The adsorption performance of activated carbon modified by redox method is better than that modified by direct ultrasonic method when adsorbing mixed solution of copper and chromium ions.

Antifungal Activity of Newly Formed Polymethylmethacrylate (PMMA) Modification by Zinc Oxide and Zinc Oxide-Silver Hybrid Nanoparticles.

Incorporating nanoparticles into denture materials shows promise for the prevention of denture-associated fungal infections. This study investigates the antifungal properties of acrylic modified with microwave-sintered ZnO-Ag nanoparticles. ZnO-Ag nanoparticles (1% and 2.5% wt.) were synthesized via microwave solvothermal synthesis (MSS). Nanoparticles were characterized for phase purity, specific surface area (SSA), density, morphology, and elemental composition. ZnO and ZnO-Ag nanoparticles were added to acrylic material (PMMA) at concentrations of 1% and 2.5% and polymerized. Pure PMMA (control) and obtained PMMA-nanocomposites were cut into homogeneous 10 × 10 mm samples. Antifungal activity of nanoparticles and PMMA-nanocomposites against C. albicans was tested using minimal inhibitory concentration (MIC) determination, and biofilm formation was assessed using crystal violet staining followed by absorbance measurements. Laboratory tests confirmed phase purity and uniform, spherical particle distribution. MIC results show antifungal activity of 1% Ag nanoparticles and the PMMA-2.5% (ZnO-1% Ag) nanocomposite. PMMA-1% (ZnO-1% Ag) nanocomposite and 1% ZnO-Ag nanoparticles are efficient in preventing biofilm formation. However, ZnO nanoparticles showed antibiofilm activity, and the PMMA-ZnO nanocomposite does not protect against biofilm deposition. Incorporating hybrid ZnO-Ag nanoparticles into PMMA is a promising antibiofilm method, especially with ZnO-1% Ag nanoparticles.

In Situ Regenerable Molecularly Imprinted Polymer Biosensor for Electrochemical Detection of Nonelectroactive Branched-Chain Amino Acids in Human Sweat.

The significant challenge in achieving in situ regeneration for conventional molecularly imprinted polymers (MIPs) restricts their promising application in continuous monitoring of biochemical molecules closely related to human health, especially nonelectroactive molecules. This is because they are either limited to a single use or require removal of imprinted templates through chemical washing steps, which is clearly impractical for sustainable monitoring. Here, a class of in situ regenerable MIP biosensors, taking nonelectroactive branched-chain amino acids (BCAAs) as templates and methyldopa as a functional monomer, was engineered to achieve repeatable in situ regeneration and in situ target recognition. The in situ regeneration was realized through an amperometric i-t technique with a negative voltage (-0.9 V) according to intrinsic isoelectric points of analytes instead of conventional wash steps. This electrochemical extraction process not only maximally repelled the imprinted templates, creating a large number of cavities (recognition sites) and significantly enhancing sensitivity, but also ensured the successful in situ regeneration of developed biosensing interfaces. The template extraction was evaluated by examining changes in the surface morphology, elemental composition, distribution, content, and interfacial properties. The developed BCAA MIP biosensors achieved sensitive target detection with the linear range from 0.001 to 10.0 μg/mL and limits of detection down to 0.45 (Leu), 0.47 (Ile), and 0.31 (Val) ng/mL. Beyond that, the biosensors demonstrated an excellent ability in decreasing biofouling, realizing repeatable in situ target detection in human sweat, and the obtained results were highly consistent with those of the enzyme-linked immunosorbent assay, indicating high feasibility, reliability, and accuracy in practical application. Meanwhile, the biosensors showed excellent specificity, selectivity, and stability.

Microstructural and Surface Texture Evaluation of Orthodontic Microimplants Covered with Bioactive Layers Enriched with Silver Nanoparticles.

Bacterial infections are a common cause of clinical complications associated with the use of orthodontic microimplants. Biofilm formation on their surfaces and subsequent infection of peri-implant tissues can result in either exfoliation or surgical removal of these medical devices. In order to improve the properties of microimplants, hybrid coatings enriched with silver nanoparticles, calcium, and phosphorus were investigated. The present study aimed to assess the microstructure of commercially available microimplants composed of a medical TiAlV (Ti6Al4V) alloy covered with organic-inorganic layers obtained by the sol-gel method using the dip-coating technique. The microstructures and elemental surface compositions of the sterile, etched, and layer-modified microimplants were characterized by scanning electron microscopy with X-ray energy-dispersive spectroscopy (SEM-EDS). Elements such as silver (Ag), calcium (Ca), phosphorus (P), silicon (Si), oxygen (O), and carbon (C) were detected on the microimplant's surface layer. The SEM observations revealed that control microimplants (unetched) had smooth surfaces with only manufacturing-related embossing, while etching in hydrofluoric acid increased the surface roughness and introduced fluoride onto the microimplants. Layers with only silver nanoparticles reduced the roughness of the implant surface, and no extrusion was observed, while increased roughness and emerging porosity were observed when the layers were enriched with calcium and phosphorus. The highest roughness was observed in the microimplants etched with AgNPs and CaP, while the AgNPs-only layer showed a reduction in the roughness average parameter due to lower porosity. Enhancing the effectiveness of microimplants can be achieved by applying selective surface treatments to different parts. By keeping the outer tissue contact area smooth while making the bone contact area rough to promote stronger integration with bone tissue, the overall performance of the implants can be significantly improved.

Surface elemental and structural analysis of ancient Indian punch-marked coins (600 to 200 BCE): insights into metallurgy and economic practices

Punch-marked coins (PMCs) are the oldest coins in India and among the most widely circulated globally, often found in hoards that highlight their extensive use. This study utilizes X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) to analyze the surface elemental composition and chemical properties of nine series (S-0 to S-VIII) of Janapada (S-0) and imperial PMCs (S-1 to S-VIII) dating from 600 to 200 BCE, housed in the Numismatic Society of India at BHU, Varanasi, based on the Gupta-Hardakar classification related to the PMCs. XRD results reveal four prominent diffraction peaks corresponding to metallic silver (Ag) in the face-centred cubic (fcc) phase, with a slight variation in d-spacing (∼ 0.05 Å), suggesting subtle changes in the lattice structure due to smaller atomic radius elements. XPS analysis shows the non-uniform distribution of different elements, with Ag being predominant, alongside copper (Cu), lead (Pb), and trace elements, including gold (Au), only in Janapada PMCs (S-0). The binding energy curves indicate that Ag and Cu are in pure metallic forms, while Pb exists as Pb₂O₃. Importantly, no silver or copper oxide peaks were detected, indicating the metals’ purity throughout the coinage process. The variations in d-spacing observed in these historical samples offer a microscopic perspective into the broader contexts of ancient economies, technologies, and cultural practices. The silver content in these PMCs decreases as Cu and Pb increase across the series up to S-V, followed by a sudden rise in S-VI, which lacks Pb. The presence of Pb induces brittleness and may serve as an indicator of the coins’ age. Additionally, the carbon detected by XPS could result from smelting, surface contamination, or environmental deposition. These findings reflect a high level of metallurgical knowledge and alloying techniques developed between the sixth and third centuries BCE. The varying Ag content raises questions about the economy and demand for coins. At the same time, the structural variations identified through XRD and XPS can aid archaeometallurgists in estimating these coins’ chronological and geographical origins, serving as valuable tools for authentication.

Surface effect of cesium and graphene quantum dots doped CaO to enhance catalytic dye degradation and bacterial inactivation with in-silico analysis

In this study, (2 and 4 wt.%) cesium (Cs) into a fixed amount of graphene quantum dots (GQDs) doped CaO quantum dots (QDs) were prepared through a co-precipitation technique. To optimize the charge transfer and decrease the electron-hole (e-/h+) pair recombination rate of CaO QDs we introduced the Cs and large surface area GQDs into CaO QDs, reducing the particle size to improve catalytic effectiveness and antimicrobial efficacy. The morphology, structural and surface analysis, elemental compositions, functional groups, and optical analysis were investigated by systematically characterizing Cs/GQDs doped CaO QDs. The increased active sites based on Cs/GQDs doped CaO QDs revealed remarkable catalytic decolorization of rhodamine B (RhB) dye (77.83%) in an acidic medium. The maximum inhibition zones have been measured as 4.85 mm using the agar well diffusion method. Additionally, molecular docking investigations were utilized to determine the mechanism underpinning the antimicrobial action of Cs/GQDs-doped CaO QDs, revealing inhibition of β-lactamase and DNA gyrase.

Optimizing Synthesis of Anionic Surfactant‐Modified Carbon Black for Enhanced Ammonium Adsorption

AbstractThe increasing levels of ammonium in wastewater pose serious environmental issues, highlighting the urgent need for effective adsorbents to facilitate its removal. Although conventional biological treatment methods have certain drawbacks, adsorption using carbonaceous materials, such as carbon black produced from waste tires, presents a promising alternative for ammonium removal. However, the use of these materials has not been thoroughly investigated. This study focuses on optimizing the synthesis of carbon black modified with anionic surfactants to improve its capacity for ammonium adsorption. Utilizing Response Surface Methodology (RSM) and a Box‐Behnken design, the optimization process examined key variables, including reaction time, surfactant concentration, carbon black dosage, and surfactant type. Comprehensive characterization of the adsorbent was conducted to analyze its surface properties, functional groups, morphology, and elemental composition. The regression models produced highly accurate results with an R2 value of 0.9437. The optimal synthesis conditions were identified as a 12.30‐hour reaction time, a surfactant concentration of 8 mmol/L of sodium dodecylbenzene sulfonate, and a carbon black dosage of 30 g, achieving an ammonium removal efficiency of 84.80 %. This study offers a scalable solution for ammonium removal in wastewater, promising practical applications and future sustainable waste management research.

Improving the performance of silver coating deposited on copper through corrosion inhibitors

Immersion silver plating is an important surface finishing technique in the integrate circuit industry. However, it often results in silver coatings with poor compactness and adhesion due to the significant difference in potentials between silver and copper. The corrosion inhibitors of copper, rather than complexing agents of silver ions, were used to improve the immersion plated silver coating performance on copper. It was found the combined use of benzotriazole and imidazole could regulate the erosion rate of the copper substrate and improve the quality of the silver coating. The effects of different inhibitors concentrations on surface morphology, elemental composition, corrosion resistance, hardness, and conductivity of the silver coating were studied. The results indicated the optimal concentration of the combined inhibitors was 0.058 mol∙L-1, which enhanced the compactness, crystallinity, and overall performance of the silver coating by passivating the copper surface and regulating the silver deposition process.

Microstructure evaluation of Si-modified aluminide coatings on IN625 deposited by slurry aluminizing process

Si-modified aluminide coatings are promising for improving oxidation and corrosion resistance in superalloys at high temperatures. This study investigated the effect of different silicon levels in the aluminizing slurry on the morphology and structure of Si-modified aluminide coatings on IN625. This process involved spraying a slurry of aluminum and silicon particles in an aqueous PVA solution onto IN625 samples, followed by heat treatment under controlled conditions - two atmospheres (air and argon) and two heating ramps (regular and flash). Surface morphologies, cross-sectional structures, elemental compositions, and phase formations were analyzed using FE-SEM, SEM, EDS, and XRD methods, while DTA analysis assessed AlSi alloy formation during heating. The results showed that higher silicon content in the slurry increased silicon incorporation in the coatings but did not reduce aluminum activity enough to deposit a low-activity aluminide coating. The inert atmosphere (argon) and flash heating promoted the co-deposition of Si and Al, resulting in Cr and Mo silicide-enriched outer layers in some samples. The aluminum content in all slurries was sufficient for consistent β-NiAl formation across different silicon levels. The average silicon content in coatings ranged from 5 to 15 wt% and depended on the slurry composition and heat treatment conditions. The Al30Si slurry produced the thickest coatings (~90 μm), with further increases in Si leading to reduced thickness. This study suggests that slurry aluminizing can be optimized to control silicon incorporation, depositing Si-modified aluminide coatings for durable, high-performance applications.

Combined influence of vanadium doping and rGO composite partnering on the photocatalytic ability of TiO2

Nowadays, the presence of noxious organic azo dye molecules in the industrial effluents is a pervasive and significant global concern as it severely affects both human and ecological well-being. In this context, vanadium-doped titanium oxide/reduced graphene oxide (TiO2:V)/rGO nanocomposite was prepared using a soft-chemical method using Cassia fistula fruit pulp extract via green synthesis and its photocatalytic dye degradation ability was investigated against a cationic (Rhodamine-B (Rh-B)) and an anionic (Eosin Yellow (EY)) dye. The nanocomposite exhibits superior dye degrading efficiency of 95% and 97% for Rh-B and EY, respectively compared to TiO2, TiO2:V, and rGO. The structural, morphological and surface elemental composition results confirm the formation of the nanocomposite. This nanocomposite TiO2:V/rGO can be used as a heterojunction photocatalyst for cost-effective dye waste removal and commercial dye detoxification processes.

Development of NiFeSx for Selective Oxygen Evolution Reaction (OER) in Alkaline Seawater: Mitigating Chlorine Evolution in Next-Gen Seawater Electrolysis Devices

Efficient seawater electrolysis for hydrogen production faces challenges like active site poisoning, chloride oxidation, and anode corrosion, necessitating the development of effective oxygen evolution reaction (OER) electrocatalysts[1]. Strategies such as enhancing OER kinetics, mitigating chloride oxidation, bolstering corrosion resistance, and integrating multifunctionality into electrocatalysts are being pursued. Researchers explore internal and external cultivation methods to optimize electrocatalyst properties while understanding structural evolution and OER mechanisms remains crucial. Seawater electrolysis, tapping into Earth's abundant seawater resources, offers a scalable solution for green hydrogen production, especially when paired with renewable energy sources[2]. It holds promise for providing energy and water to offshore areas and mobile maritime systems, crucial for addressing energy and environmental challenges. In this study, we have fabricated a PGM (platinum group metal) free anode that shows promising performance in alkaline seawater. The material consists of nanoclusters of FeNiSx.This study applied a polyol-assisted hydrothermal synthesis strategy to describe an advanced procedure for synthesising NiFeSx. Several physical and chemical characterisation tools are applied to investigate the anode electrode for alkaline seawater oxidation XRD, SEM, TEM and electrochemical characterisation. The outcomes of these characterisations were displayed as graphs. The catalysts reveal nanocluster morphologies. The figure below depicts the preliminary findings, illustrating the electrochemical performance and the physical characterisations. Figure 1 (a) and (b) depict the morphological evaluation by electron microscopy revealing the nanostructure-based clusters of the produced materials with the scanning and transmission electron microscopy, respectively. In. Polarisation curves of the oxygen evolution activity of the synthesised NiFeiSx electrocatalysts on Ni foam working electrodes, in a three-electrode configuration with Pt wire serving as the counter and Hg/HgO serving as the reference electrode in 0.1M KOH + 0.5 NaCl electrolyte. The best-performing catalysts obtained a high current exchange density close to 225 mAcm-2 shown in Figure 1(c). In addition, we are evaluating the efficacy of this high-performance anode electrocatalyst in a single-cell electrolyser and the best and most stable catalyst will be tested in stacks we are developing with our partners in the ANEMEL project.Our research methodology encompasses a comprehensive array of ex-situ and in-situ characterization techniques to delve into the intricacies of seawater electrolysis for hydrogen production. We will utilize impedance spectroscopy to dissect electrochemical behaviour, including resistance, capacitance, and charge transfer resistance. Additionally, chronopotentiometry/chronoamperometry will assess the catalyst's long-term stability, while real-time examination of catalyst crystal structure during OER will be facilitated by Powder X-ray diffraction (XRD). Surface chemistry and elemental composition analysis will be conducted using X-ray photoelectron spectroscopy (XPS), while in-situ Raman spectroscopy will offer insights into electronic structure changes during the reaction, shedding light on the OER mechanism. Furthermore, FTIR spectroscopy will unveil reaction intermediates and mechanisms, providing a detailed understanding of the reaction pathway. Post-mortem catalyst analysis post-electrochemical testing will evaluate degradation, ultimately aiding in optimizing catalyst design for long-term stability and high-performance OER. Acknowledgements The authors acknowledge the ANEMEL Project funded by the Horizon Europe (European Innovation Council) Grant agreement 101071111. Figure 1

Carboxylic acid-based fuel mediated sustainable one-pot fabrication of CaFe2O4 with enhanced adsorptive elimination of hazardous dye

The present work successfully demonstrated the morphological variation of CaFe2O4 (CFO) concerning various fuels (carboxylic acid groups contain compounds) using a one-step combustion technique. The SEM analysis of the CFO suggests the formation of sharp-edge rocky crystals to highly agglomerated porous clumps concerning the role of fuel. The x-ray diffraction analysis suggests that all samples of CFO are nanocrystalline orthorhombic structure constituted <50 nm. The BET and EDX analysis discloses that CFO s surface area and element composition is highly depend on the fuel molecule (reducer). The CFO performs efficacious in the adsorptive removal of hazardous dye Acid Fuchsin (AF) from an aqueous medium in a slightly acidic environment (pH 6). The AF removal was engaged with the batch adsorption method and optimized the process’s essential parameters (amount of adsorbent, initial AF concentration, and time) were optimized to achieve the utmost efficiency. The AF adsorption was well described by the Langmuir isotherm with outstanding adsorption capacity in the order of CFO-OA (Oxalic acid) (866) < CFO-TA (Tartaric acid) (1063) < CFO-CA (Citric acid) (1504) < CFO-MA (Malonic acid) (1656 mg/g). The adsorption energies were estimated from the Dubinin-Radushkevich model, indicating that adsorption occurs via the chemical process. The pseudo-second-order (PSO) kinetic model was better at explaining the uptake of AF, and the Intraparticle diffusion model indicated that pore diffusion was the rate-controlling step. The reusability test shows that the CFO has high efficiency up to five regeneration cycles. Thus, the work suggests that CFO could be an eco-friendly, cost-effective alternative adsorbent for wastewater treatment.

Effect of different ratio KOH treatment on neem bark in the formation of activated carbon: Adsorption characteristics study

In this study, mature neem tree bark (NB) was chemically transformed into an activated carbon (NBAC) through different ratios (1:1, 1:2, 2:1, 1:3, 3:1) of KOH and NB biomass. The obtained Neem bark-activated carbons (NBAC-1, NBAC-2, NBAC-3, NBAC-4, and NBAC-5) were tested for methylene blue (MB) dye removal efficiency. The NBAC-1 was found to be highly effective against MB dye. The NBACs have a low Brunauer-Emmet-Teller (BET) surface area (10.8 m2/g) with surface functional groups dominated by -OH and -CO. It is thermally stable up to 700°C, and its surface elemental composition is mainly carbon, oxygen, and potassium. The adsorption characteristics against MB dye show that 99.15% of dye from 100 mg/L initial concentration solution was removed with 4 g/L NBAC-1 dosage in 200 min of contact time at 50°C solution temperature, and pH of 10 (pHzpc = 7.85), resulting in an adsorption capacity of 24.79 mg/g. Kinetic studies indicated that the adsorption process of MB dye utilizing NBAC-1 adhered to the linear pseudo-second-order (R2 = 0.9726) and nonlinear Elovich model (R2 = 0.9419), signifying chemisorption, alongside the nonlinear Weber-Morris model (R2 = 0.9231), highlighting the significance of mass diffusion of MB dye onto the NBAC-1 surface in multilayers. Isotherm investigations favored better conformity with the Freundlich model, exhibiting a higher R2 value of 0.999, suggesting a heterogeneous multilayer adsorption mechanism. Adsorption thermodynamics analysis inferred that the adsorption was feasible (∆G = -4.342 KJ/mol), endothermic (∆H = +50.0203 KJ/mol), and demonstrated a high affinity of NBAC-1 towards MB dye (∆S = +168.2255 J/K/mol). Recyclability of the NBAC-1 adsorbent was also conducted to check for its sustainable usage.

Nano-pumice derived from pumice mine waste as a low-cost electrode catalyst for microbial fuel cell treating edible vegetable oil refinery wastewater for bioenergy generation and reuse

This study aimed to assess nano-pumice (NP) from pumice mining waste as a local, cost-effective anode catalyst in microbial fuel cells (MFCs) for treating edible vegetable oil refinery wastewater (EVORW) and generating bioenergy. Pumice mining waste was converted into nano in three stages: crushing up to ≤3 cm, reducing the size of the previous step particles to 150 μm and converting the previous step particles to <100 nm. Nano-pumice prepared was coated on the carbon cloth (CC) to increase anode surface area of MFC. Two MFCs were utilized, with MFC-1 serving as a control and MFC-2 incorporating a CC electrode coated with nano-pumice. The surface morphology, elemental and chemical composition, and textural characterization of CC, pumice, NP, and CC coated with NP were analyzed using FE-SEM, EDX, XRF, and BET techniques. MFC-2 achieved a maximum power density of 30±4W/m³ at a current density of 55±5A/m³. The MFC-1 reached a maximum power density of 18±4W/m³ at a current density of 35±6A/m³. In MFC-2, the EVORW treatment achieved maximum removals of COD (94 ± 2 %), NH4+-N (85 ± 4 %), TP (76 ± 5 %), SO42− (68 ± 6 %), TSS (81 ± 2 %), and TDS (73 ± 1 %). MFC-1 achieved removal efficiencies of 66 ± 3 % for COD, 57 ± 6 % for NH4+-N, 48 ± 3 % for TP, 45 ± 3 % for SO42−, 65 ± 3 % for TSS, and 61 ± 1 % for TDS. MFC-2 power density rose significantly, reaching 61 ± 3 % (1.6 times) higher than MFC-1and it also demonstrated a superior ability to improve raw wastewater quality compared to MFC-1. The MFC with the CC/NP anode exhibited both excellent power production and high COD removal efficiency, making nano-pumice a suitable anode catalyst for MFC applications.

Enhancing coloration performance and colour fastness of nano‐pigment ink‐jet‐printed blended fabrics through cationic and water‐repellent surface modification

AbstractThe coloration performance and colour fastness properties, crucial for industrial textile printing, depend on the spreading and fixation behaviour of ink‐jet droplets on porous fabrics. Current nano‐pigment‐based ink‐jet applications provide unstable results for these properties, especially for synthetic and blended fabrics. This study focuses on cellulose‐based blended fabrics as substrates to modify the wetting properties of fabrics through cationic and water‐repellent treatments, to improve the coloration performance and colour fastness systematically. The study conducted analytical experiments to analyse the surface element composition, ion potential and surface morphology of the fabrics. Differences in printing colour and pattern performance were attributed to the behaviour of ink droplet spreading on the fabric surface and inside the fabric, including wetting time, colourant distribution, and ring shape. The results indicate that ink droplet spreading on fabrics significantly influences printing pattern sharpness, including edge clarity and colour intensity, which can be improved through surface modification, including cationic and water repellent treatment. The use of blended fabrics treated with 1% cationic modifier and 0.05% fluorine‐containing water repellent resulted in effective suppression of droplet formation and significant enhancement of colour performance and fastness. Furthermore, as the ink droplet volume decreased from 5 to 1 μL, the coffee ring effect on the fabric treated with the water repellent agent gradually diminished, leading to improved printing sharpness during the printing process.

Effect of ultraviolet treatment on soft tissue healing and bacterial attachment to titania-coated zirconia

Zirconia is the most promising implant abutment material due to its excellent aesthetic effect, good biocompatibility and corrosion resistance. To obtain ideal soft tissue sealing, the implant abutment surface should facilitate cell adhesion and inhibit bacterial colonization. In this study, pre-sintered zirconia was placed in a suspension of titania (TiO2) and zirconium oxychloride (ZrOCl2) and heated in a water bath for dense sintering. A titania coating was prepared on the zirconia surface and subjected to UV irradiation. The surface morphology, elemental composition and chemical state of each group of samples were analyzed by scanning electron microscope, x-ray energy spectrometer, x-ray photoelectron spectroscopy and x-ray diffraction. The responses of human gingival fibroblasts (HGFs) and common oral pathogensStreptococcus mutans(S. mutans) andPorphyromonas gingivalis(P. gingivalis) to modified zirconia were systematically assessed. Our findings demonstrated that the surface of titania-coated zirconia after UV irradiation produced a large number of hydroxyl groups, and its hydrophilicity was significantly improved. Meanwhile, the UV irradiation also greatly removed the hydrocarbon contaminants on the surface of the titania-coated zirconia. The UV-treated titania coating significantly promoted the proliferation, spreading, and up-regulation of adhesion-related genes and proteins of HGFs. Furthermore, the titania coating irradiated with UV could reduce the adhesion, colonization and metabolic activity ofS. mutansandP. gingivalis. Therefore, UV irradiation of titania-coated zirconia can promote the biological behavior of HGFs and exert a significant antibacterial effect, which has broad clinical application prospects for improving soft tissue integration around zirconia abutments.