Increase In Doping Concentration Research Articles

Static disorder in perovskite-type proton-conducting oxides BaSn1-xMxO3-x/2-(y/2)H2O (M = Ga, Sc, In, Y, La): a novel approach based on statistical analysis of numerous DFT simulated structures.

Perovskite-type proton-conducting oxides inherently include defects such as substitutional aliovalent cations, oxide ion vacancies, and interstitial protons. These defects introduce static disorder into their crystal structures. To investigate such disorder in BaSn1-xMxO3-x/2-(y/2)H2O (M = Ga, Sc, In, Y, La), we employ a novel approach based on density functional theory (DFT) simulations. This approach involves the structural optimization of a large number of relatively small, randomly constructed supercells, followed by statistical analysis of their geometric, energetic, and vibrational properties. Our key findings are as follows. The structural disorder becomes more pronounced as the dopant concentration increases, and as the dopant ionic radius increases from Sc to La. The O-H covalent bond lengths, as well as the number densities, of hydrogen atoms display clearly different distributions depending on whether the hydrogen atoms are trapped by aliovalent cations or not. The hydrogen-trapping energies appear to decrease as the geometric similarity of O-H covalent bonds between trapped and untrapped hydrogen atoms increases. Hydrogen atoms simultaneously trapped by more than one dopant atom exhibit considerable stability, potentially hindering proton diffusion at high dopant concentrations. The O-H stretching wavenumber decreases as the O-H covalent bond length increases, showing a very strong and nearly linear correlation between the two. The simulated IR absorption spectra show semi-quantitative agreement with the measured spectra. These new findings demonstrate the effectiveness of the present 'statistical' approach for investigating static disorder.

Effect of laser heating on partial decomposition of ZnCo2O4 nanoparticles: Raman study

We conducted a comprehensive investigation into the nanostructuring of the ZnO/CoO mixture by laser heating and optical attributes of partial decomposition of the obtained two-phase system represented by ZnO and ZnCo2O4. Starting mixtures were obtained across a broad range of dopant, CoO, concentrations, spanning from 5 % to 90 % of CoO. The samples were methodically prepared using the coprecipitation method and subjected to calcination at 600 °C. Laser-induced heating experiments were conducted at nine distinct laser powers. The characterization of these samples was accomplished through the utilization of SEM, XRD, and Raman spectroscopy. XRD analysis unveiled the presence of ZnO and ZnCo2O4 phases. Concurrently, we systematically monitored nanostructuring effects caused by laser-induced heating, the influence of partial decomposition on the behavior of surface optical phonons (SOP), and phase transitions in the samples with varying dopant concentrations during the performed experiment. New phases, including Zn1-xCoxO, ZnyCo3-yO4, CoO, and even the Co3O4 phase, were unveiled. The Raman spectra obtained distinctly indicate the presence of surface optical phonons (SOP), emphasizing the existence of the ZnO phase. The alterations in the behavior of surface optical phonon (SOP) modes were meticulously examined by laser-induced heating nanostructuring effects where it became evident that there was a discernible loss of these modes with an increase in dopant concentration and laser power. This detailed study sheds light on the intricate interplay between dopant concentration, laser power nanostructuring, partial decomposition, and the evolution of phase transformations and surface optical phonon modes in the examined samples.

Stoichiometry modulated tunable optoelectronic properties of Nb-doped WS2 synthesized by chemical vapor deposition method.

Significant progress has been made in the field of two-dimensional WS2, yet the precise control of the doping process to achieve desired properties and the interpretation of complex physical phenomena in these novel materials necessitate thorough research. In this study, Nb-doped WS2 is synthesized using chemical vapor deposition technology, leading to triangular flakes with a side length of 12-20μm. The X-ray photoelectron spectroscopy analysis indicates that the NbW substitution defect functions as an electron acceptor. The interlayer and transverse forces of the Nb-doped WS2 flake approach 1 nN and 150 pN, respectively. As the doping concentration increases, the valence band maximum energy of Nb-doped WS2 ranges from 4.06eV to 4.3eV. Furthermore, the performance of the photodetector is discussed.

Synergistic modulation of SrTiO3-TiO2 colossal permittivity system by internal lattice defects and phase composition: Experimental and theoretical investigations

The SrTiO3–TiO2 composite ceramics with different contents of La doping were fabricated by traditional solid-state sintering methods. The performance of the colossal permittivity ceramics was enhanced by the synergistic design of the internal defect structure and phase composition. When the doping content is 2%, SrTiO3–TiO2 composite ceramics possessed a colossal permittivity (ԑr ∼ 1.1 × 105), low dielectric loss (tanδ ∼ 0.050) and favorable thermal stability (−70 °C-150 °C, ΔC/C25°C ≤ ±15%). Phase structure analysis suggested that a TiO2 secondary phase was induced at the grain boundaries of SrTiO3 phase with the addition of La3+ ions. XPS and dielectric behavior analyses revealed that oxygen vacancies and lattice defects formed by inhomogeneous ion-doping act to modulate the dielectric behavior in ceramics. The IBLC interfacial effects in relation to semiconductor grains and insulation grain boundaries are the main contributors to the colossal permittivity (CP) properties of ceramics, and the contribution of the IBLC effects becomes more prominent with increasing doping content. On the basis of first-principles analysis, the ceramic lattice undergoes severe deformation when the La content is increased, and the gathering of electrons at oxygen vacancies and defects is evident. As a result, it leads to enhanced grain semiconducting properties and interfacial effects, which facilitate colossal permittivity and low dielectric loss for ceramics. The results are prospective in the application of CP ceramics.

First-principle study of the effect of Hf doping and VO-Hi co-existence on absorption spectrum, conductivity and carrier activity of β-Ga2O3

At present, some progress has been made in the study of Hf doping on the conductivity. However, few studies on the effects of Hf doping, and O vacancy and interstitial H co-existence on photoelectric properties of β-Ga2O3. O vacancy and interstitial H will inevitably exist during the preparation of β-Ga2O3. Given these problems, the effects of Hf doping, O vacancy and interstitial H co-existence on photoelectric properties of β-Ga2O3 were studied using first-principles calculations. Results show that doping and defects affect the photoelectric properties of β-Ga2O3 to some extent. With increased Hf doping concentration, the bandgap of the system decreases gradually, the absorption spectrum in the deep ultraviolet region red shifts, the carrier activity and carrier lifetime are enhanced. The mobility and conductivity of the system also increase with increased doping concentration. The Hf doping and interstitial H can effectively improve the conductivity of the system. In summary, Hf can be used as a powerful candidate material for designing and preparing β-Ga2O3 optoelectronic devices.

Study on the Effect of Ce Doping Concentration on the Kinetics of Graphene Formation

The thermodynamic and kinetic processes of Ce-doped graphene were simulated by the method of first-principles molecular dynamics. The structural optimization and annealing, the kinetic properties of Ce-doped graphene composites were calculated by the classical mechanics Forcite module. The results show that with the increase of Ce doping concentration, the order of the radial distribution function in the system increases and presents a state of aggregation. According to the analysis of mean azimuth shift function, the mean square displacement (MSD) value of Ce doped graphene composite increases with the increase of doping concentration, and the corresponding diffusion coefficient also increases. The research of gyration radius and gyration evolution radius shows that with the increase of temperature and doping concentration, the gyration evolution radius of atoms becomes shorter and shorter, indicating that the interatomic force in the system is enhanced and the range of activity is shortened. Combined with the analysis of local cluster structure, it can be seen that the maximum cluster size and number of Ce doped graphene composites do not change significantly with the increase of doping concentration, indicating that Ce atom doping will improve the order in the system, increase the diffusion coefficient and enhance the interaction force between atoms. The paper aims to reduce the error between the theoretical properties and the actual properties, and provide a theoretical basis for the development of new materials with excellent properties.

Exploration of laser-assisted chemical bath for enhancing synthesis of undoped and nickel-doped zinc oxide and its potential applications in water purification and mitigating antimicrobial resistance

This study aims to explore the antimicrobial and photocatalytic efficiencies of pure and Ni-doped ZnO nanostructures produced via Laser-assisted Chemical Bath Synthesis (LACBS) to develop sustainable solutions for water treatment and pathogen control amid the global water crisis exacerbated by climate change and environmental pollution. Utilizing zinc acetate dihydrate and hexamethylenetetramine, the nanostructures were synthesized with Ni doping levels of 0.0 %, 1.5 %, 3.0 %, and 4.5 %, targeting their promising photocatalytic and antimicrobial properties to combat contaminants from pharmaceuticals, agriculture, and industries. Morphological analyses using Scanning Electron Microscopy showed a transition from hexagonal particles to nanoflowers, enhancing photocatalytic activity due to increased surface-to-volume ratio. X-ray Diffraction confirmed the hexagonal wurtzite structure, with variations in peak intensities indicating improved crystallinity with Ni doping. Energy Dispersive X-ray analysis verified the purity and successful incorporation of Ni. Photocatalytic assessments indicated up to 99.24 % degradation of Methylene Orange dye under blue laser irradiation within 60 minutes, correlating with Ni content. Antimicrobial tests demonstrated effective inhibition of pathogens such as Escherichia coli, Staphylococcus aureus, and additional strains like Candida albicans and Klebsiella pneumonia, with increasing zones of inhibition corresponding to higher Ni levels, extending up to 37 mm. The results underscore the dual functionality of ZnO nanostructures for applications in sustainable water treatment and antimicrobial controls, highlighting the need for future studies to examine the impacts of further increased doping concentrations on the material properties and efficacy.

Understanding Spin-Orbit-Coupling-Induced Reverse Intersystem Crossing in DMAC-TRZ-Doped Organic Light-Emitting Diodes via Magnetic-Field-Effect Measurement.

An efficient reverse intersystem crossing (RISC) process in thermally activated delayed fluorescence (TADF) material is a common way to obtain high-performance organic light-emitting diodes (OLEDs), but the physical mechanism for the spin flipping of the RISC remains vague. Here, using magneto-electroluminescence (MEL) as an effective tool, we found that the RISC (CT3 → CT1) from a triplet charge transfer (CT3) to the singlet charge transfer (CT1) state is decided by spin-orbit coupling (SOC) in metal-free OLEDs based on a typical TADF emitter DMAC-TRZ. By fitting and analyzing the current and concentration-dependent MEL data, it is found that the characteristic magnetic field of the SOC-induced RISC process is approximately 65-85 mT, which is obviously larger than that (several mT) of the hyperfine-interaction-induced RISC process. Simultaneously, the dissociation effect of the electric field on the CT3 state causes the SOC-induced RISC process to decrease with increasing bias current. The different formation methods of excited states lead to the nonmonotonic change of SOC-induced RISC process with the increase of dopant concentration. Furthermore, considering the orbital polarization of dipoles, the SOC mechanism is further verified by the measurement of magneto-photoluminescence to be the responsible for achieving the spin flipping in TADF molecules. Therefore, this work clarifies the underlying dynamic mechanism of the RISC process in TADF-OLEDs.

Prospect for detecting magnetism in two-dimensional perovskite oxides by electron magnetic circular dichroism

Two-dimensional (2D) magnets, especially strongly correlated 2D transition-metal perovskite oxides, have attracted significant attention due to their intriguing electromagnetic properties for potential applications in spintronic devices. Potentially electron magnetic circular dichroism (EMCD) under zone axis conditions can provide three-dimensional components of magnetic moments in 2D materials, but the collection efficiency and the signal-to-noise ratio for out-of-plane (OOP) components is limited due to the limited collection angle. Here we conducted a comprehensive computational simulation to optimize the experimental setting of EMCD for detecting the OOP components of magnetic moments in three beam conditions (3BCs) on 2D perovskite oxides La1-xSrxMnO3 (LSMO) in a TEM. The key parameters are sample thickness, accelerating voltage, Sr doping concentration, collection semi-angle and position, and sample orientation including systematic reflections excited and tilt angle. Our simulation results demonstrate that the relative dynamical diffraction coefficients of Mn OOP EMCD of LaMnO3 with a thickness ranging from 1 unit cell (uc) to 4 uc can be optimized in a 3BC with (110) systematic reflections excited and a relatively large collection semi-angle of 19 mrad at the relatively low accelerating voltage of 80 kV. In most cases, the relative dynamic diffraction coefficients for La1-xSrxMnO3 with the thickness ranging from 1 uc to 4 uc decrease with the increase of the Sr doping concentrations. The optimal tilt angle from a zone axis to a 3BC is 18° for the cases of the LSMO thickness of 2 uc, 3 uc and 4 uc, and 22° for the monolayer LSMO. Our work provides the theoretical simulation foundation for optimized EMCD experiments for measuring OOP components of magnetic moments in 2D transition-metal perovskite oxides.

Solar light driven enhanced in photocatalytic activity of novel Gd incorporated ZnO/SnO2 heterogeneous nanocomposites

The Gd-doped ZnO/SnO2 nanocomposites with various atomic percentages (0, 0.5, 0.8, and 1.2 at%) of gadolinium (coded as GdZS0, GdZS1, GdZS2, and GdZS3) was synthesis via the sol–gel method and explored for photodegradation against dye solutions exposing solar light irradiation. The synthesized nanocomposites were characterized employing the XRD, FTIR, FE-SEM, Raman spectroscopy, BET analysis and UV–Vis spectrophotometer. The FE-SEM results indicated that the formation of nanoparticles to nanoflowers covered with Gd ions was observed with an increased doping concentration of Gd. The optical bandgap was evaluated and found in the range of 3.21–3.27 eV for GdZS nanocomposites. The GdZS nano-photocatalysts were investigated against the degradation of different organic dyes and GdZS3 shows the highest degradation efficiencies of 99.3%, 98.3% and 99.4% towards MO, MB and RhB dyes, respectively at neutral pH in aqueous media. Before and after photodegradation. Biological oxygen demand and chemical oxygen demand tests to make estimations of mineralization. The investigations are very promising for the degradation process in rare earth doped metal oxide nanocomposites. A plausible photodegradation mechanism of synthesized nanocomposites under investigation has also been proposed.

Synthesis, optimization, electrochemical and electrochromic properties of Zr-doped NiO films by chemical spray pyrolysis

Zirconium (Zr)-doped NiO films with different contents were successfully synthesized via the chemical spray pyrolysis technique. The structure, morphology, optical and electrochemical behaviors of these films were investigated by X-ray diffraction (XRD), Raman spectrometer, scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), UV–Vis-NIR spectrophotometry, cyclic voltammetry (CV), and chronoamperometry (CA). XRD results suggested that the synthesized samples have the cubic crystal structure and a preferred orientation along the plane (111). Raman spectra further confirmed the successful incorporation of zirconium ions into the NiO films. SEM images explained that the surfaces of the doped films were composed of uniform and dense nanoparticles. EDS analysis suggested that Zr, Ni and O elements were uniformly distributed on the films. The optical results showed that the band gap decreases from 3.53 eV to 3.47 eV as the increase of zirconium doping content. The electrochemical analysis suggested that zirconium doping improved the specific capacitance of the NiO films (the NiO film with the Zr amount of 7 %, 59 F/g at 6 mV/s). In addition, the NiO film with 5 % Zr doped amount exhibited the largest ΔOD (81 %), the largest CE (60.37 cm2/C), and the fastest coloring time (tc =2.1 s) and bleaching time (tb = 2.4 s). These results showed that this film had the excellent electrochromic properties, suggesting that the optimal Zr doped amount of NiO films is 5 %. As a novel kind of electrochromic material, the Zr-doped NiO film has broad application prospects in smart windows, green buildings and energy efficient utilization fields.

Enhanced transport anisotropy of Bi film through carrier mobility modulation controlled by calcium metal

Ca-doped Bi films were fabricated on the glass substrate using the molecular beam epitaxy (MBE). The systematic evolution for the preferred orientation, transport properties and surface morphology of Bi films were observed in the change of doping content. The measurement results show the adjustability of the preferred orientated surface morphology and Bi film carrier mobility. As the doping content increases, the mobility ratio four-fold and increases the anisotropy. Transport measurement simplifies the characteristic analysis of topological quantum materials. This work controls the material quantum property by doping Ca using MBE, which extends the potential application of quantum anomalous Hall effect-based devices.

Mechanical properties and multi-field ferroelastic response of Nb/Mn Co-doped CaBi4Ti4O15 high-temperature ferroelectric ceramics

CaBi4Ti4O15 (CBT) ceramics are promising piezoelectric materials that have been widely studied for high-temperature applications. Despite significant advancements in the electrical performance of CBT ceramics, the understanding of their mechanical behaviors remains limited, which is unfavorable for designing ceramics with high stability and reliability during high-temperature service. This work investigated the mechanical properties and fracture behaviors of Nb/Mn co-doped CaBi4Ti4O15 (CBTNM) with various doping levels, focusing on stress-strain responses and ferroelastic deformation behaviors under uniaxial compression and multi-field coupling conditions. HRTEM analysis reveals small-scale layered domain wall structures on the surface of plate-like grains. The fracture and compressive strengths of CBTNM ceramics initially decrease and then increase with an increase in doping content, and the underlying mechanisms are related to grain size, defects, and densification. CBTNM ceramics exhibit nonlinear stress-strain responses due to ferroelastic deformation under compressive loading, and the resultant irreversible domain switching strain increases with an increase in doping content, while poling can further increase the residual strain. Under multi-field loading conditions, CBTNM ceramics undergo more ferroelastic deformation events and exhibit larger residual strain. The micro-cracks, pores, complicated fracture modes, and degraded fracture surfaces with fragmental and rough features are mainly responsible for the lower elastic modulus and inferior mechanical response. This work enhances our understanding of the mechanical behaviors of high-temperature piezoelectric ceramics and provides guidance for designing high-performance piezoelectric materials for complex environmental applications.

Influence of Ni2+ on OER kinetics and photoluminescence properties of ZnSnO3 nanoparticles

Ni2+ doped ZnSnO3 nanoparticles (NPs) were synthesized using Aloe vera mediated solution combustion method, followed by an investigation into their luminescence and oxygen evolution reaction properties. The Bragg reflections of ZnSnO3: Ni(1–9 mol%) NPs revealed a cubic structure, with the addition of the dopant inducing lattice strain and resulting in peak shifting towards higher angles. No impurity-related peaks were observed. The estimated crystallite size and optical band gap decrease (3.1–2.94 eV) with an increase in dopant concentration. The surface morphology consists of irregular-sized and shaped NPs with hallows. The EDAX spectra show the purity of the sample. Photoluminescence emission spectra were recorded at a 230 nm excitation wavelength, where intense blue emission observed at 482 nm was attributed to a direct transition between the conduction band edge and the valence band edge, corresponding to the direct recombination of free excitons. Another satellite peak observed at 525 nm can be attributed to oxygen deficiency. Moreover, the nanoparticles exhibited outstanding performance in oxygen evolution reaction studies, showing low over potentials between 300 and 318 mV, a minimal Tafel slope of range 63–72 mV dec−1, and stable electrochemical behavior over 12 h at a current density of 23 mA/cm2. These results highlight their effectiveness as electrocatalysts.

Effects of Gd2O3 additives on microscopical morphology of ZrB2-SiC sintering ceramic system: Insights for electron transpiration cooling

By manipulating the work function, the dissipation of thermal energy on the material surface can be regulated through Electron Transpiration Cooling (ETC) mechanism. The doping of rare-earth oxide serves as an effective approach for reducing the work function, whereas there is still a lack of comprehensive research into the microstructural morphology of the rare-earth oxides and their correlations with the modifications of the work functions. This study investigates the detailed microscopical structure of Gd2O3 in the ultrahigh-temperature ceramic system (ZrB2-20 vol%SiC). Semi-quantitative composition analyses based on X-ray photoelectron spectra indicate that an increased doping concentration of Gd2O3 is beneficial for the formation of a single solid-state Gd0.18Zr0.82O1.91 phase of ZrB2-SiC system. Atomic-scale scanning transmission electron microscopy (STEM) analyses suggest that Gd2O3 is enriched at the interfaces between SiC and ZrB2 matrix with a nanoscale fibrous morphology composed of alternated Gd2O3 crystals and pores, rendering a continuous microstructure throughout the entire system. This peculiar microstructural morphology is anticipated to facilitate its diffusion along the grain boundary and the formation of Gd2O3 nanolayers at the surface region below the melting points of the ceramic matrix, which can efficiently lower the material work function and reduce the emission energy of the surface electrons during thermal emission through ETC mechanism. The composite with 10 vol% Gd2O3 induces a reduction of the averaged work function of ∼0.49 eV before preforming the thermionic emission experiments. Our results provide valuable insights into the impacts of rare-earth oxide on the ZrB2-SiC matrix, as well as shed light on the feasibility of the ETC mechanism through the efficient design of thermal protection materials.

Performance optimization of eco-friendly CH3NH3SnI3 based perovskite solar cell employing CH3NH3SnBr3 as hole transport layer by SCAPS-1D device simulator

This study focuses on the theoretical aspects of third-generation perovskite solar cells (PSC), with the aim of replacing traditional silicon-based counterparts. With potential for higher efficiency and low manufacturing costs, perovskite cells offer unique crystallographic structures allowing adjustments to photoluminescence wavelength. This research addresses challenges in cost-effective solar spectrum utilization and optimization of parameters, device architecture, and materials for high-efficiency cells. In this study, we simulated a perovskite-based solar cell (CH3NH3SnI3) using solar cell capacitance simulator-one dimension simulator under AM 1.5G illumination. The chosen electron transport layer is TiO2, and hole transport layer is CH3NH3SnBr3. The simulation explores variations in layer thickness, defect concentration, interface defects, doping concentration and electron affinity. Additionally, we analyzed the impact of back metal contact work function and temperature variations. Results indicate optimal absorber layer thickness at 0.5µm. Reduced defect concentrations, increased doping concentration and a higher work function for the back contact, enhance efficiency of PSC. The initial parameters yielded a 19.79% efficiency based on base values before optimization, which increased to 26.66% after optimization. According to the latest NREL data, the highest reported efficiency for PSC is 26.1%. This research provides insights into perovskite-based solar cell design for enhanced efficiency.

Electrochemical and photoluminescence properties of Ce3+ doped copper aluminate nanoparticles

In this communication, for the first of its kind, CuAl2O4 doped with Ce3+ (1-9 mol %) are syn- thesized by solution combustion method using Aloe Vera gel as a reducing agent. The as-formed sample was calcined at 500° C for 3 hours, followed by characterization. The addition of dopants to the copper aluminate matrix didn't alter the crystal structure of the host matrix. Bragg reflec- tions confirm the formation of the cubic phase and also absence of other impurities. The surface morphology consists of nanorods arranged one above the other. The estimated crystallite size was found to decrease from 12 to 9 nm whereas, the direct energy band gap increases from 2.84 to 3.02 eV with an increase in dopant concentration. Under λex = 305 nm excitation, photoluminescence (PL) emission spectra have a high intense peak at 553 nm along with a less intense peak at 472 nm. The peak at 553 nm can be attributed to the existence of oxygen vacancies which arise due to the transition of an electron from the 2D3/2→2F7/2 of Ce3+, however, the peak observed at 472 nm results from the transition of ionized oxygen vacancies (VO) to the valence band caused by the 2D3/2→2F5/2 transition. The CIE coordinates lie well within the green region with 5758 K aver- age CCT. Further, Cyclic voltammetry analysis was conducted to investigate oxidation and redox peaks, while electrochemical impedance spectroscopy provided insights into ion transport kinetics. Specific capacitance values ranging from 29 to 59 F/g were obtained for CuAl2O4:Ce(1-9 mol %) NPs. These findings suggest potential applications for the synthesized material in areas such as display technology as a green nano phosphor and energy storage materials.

Prediction of ferromagnetism in GaN:Ag and SiC:Ag nanotubes

Ferromagnetism in single-walled (6,0) GaN(SiC):Ag nanotubes were studied based on ab initio simulations within a pseudopotential method. For the GaN:Ag single-walled nanosystems, the width of the band gap reduces with the increase of dopant concentration. While Ag-doped SiC nanotubes, the band gap of majority-spin states decrease and these systems show metallic character. The first-principles results of total energies for SiC(GaN):Ag nanotubes predicted the stability of the ferromagnetic and antiferromagnetic phase, respectively. The obtained values of total magnetic moments of Ag-GaN and Ag-SiC systems are ∼2.0 and ∼3.2 μB, respectively. The analysis of the results of density of states show the significant contribution to the magnetization of both defected GaN:Ag and SiC:Ag systems come from three nitrogen and carbon atoms which are bonded with the dopant. First-principles investigation, suggest that the SiC(GaN):Ag nanotubes can be made into magnetic materials, and these are promising candidates for electronic, optoelectronic, and spintronic devices.

Mg doped ZnO containing silk nanocomposite scaffolds for biofilm prevention during alveolar bone regeneration

Biofilms are created when micro-colonies adhere to a solid surface and produce a strong extracellular matrix which increases the risk of infection and impedes the healing process of bone defects. Although post-operative antibiotics are commonly prescribed to prevent infections, they carry the risk of side effects and antibiotic resistance. Current research explored the potential of magnesium doped zinc oxide incorporated silk fibroin scaffolds to prevent the biofilms formation for alveolar bone regeneration applications. Novel silk fibroin (SF)/hydroxyapatite (HA) scaffolds incorporated with magnesium-doped zinc oxide nanoparticles (Mg–ZnO NPs with 0.5, 1 and 2 % Mg) were fabricated by freeze gelation method. The data suggested that new materials exhibit remarkable antibacterial activity against Staphylococcus aureus. Moreover, these materials are also found to be both biodegradable and biocompatible. The study revealed that scaffolds displayed excellent antibacterial activity that was increased with increasing concentration of Mg in ZnO, with a maximum of 49.39 % was observed for 2 % of Mg doped ZnO. Additionally, biodegradation of the material also increases with the increase in concentration of Mg doping in ZnO. The adequate porosity in the range of 67 %–74.3 % was recorded of new materials substituted with Mg–ZnO, which led to improved cell viability (99.6 %) and uniform deposition of apatite over the surface of scaffolds, making it an excellent candidate for biomedical applications that require antibacterials properties with high cell viability.

Enhanced dielectric, magnetic, and photocatalytic properties of sol-gel synthesized Eu-Cr codoped BiFeO3 nanoparticles

A series of polycrystalline Eu-Cr co-doped BiFeO3 nanoparticles were synthesized using the sol–gel method. The obtained samples were characterized by employing the XRD, FTIR, FESEM, UV–vis, LCR meter, and SQUID techniques. XRD analysis confirmed rhombohedral phase formation for all samples, and the crystallite sizes decreased with higher Cr3+ doping concentrations. The stretching and bending vibrations of Fe-O bonds in FeO6 octahedra and the formation of perovskite nature were confirmed by the FTIR analysis. From microstructural studies, a decrease in crystallite size with increased doping concentration was observed, corroborating the XRD results. The magnetic studies revealed an enhanced magnetization, probably caused by the distorted cycloid spin structure of the codoped nanoparticles with size ≤62 nm. The lower value of the squareness ratio of the M-H loop indicated strong magnetostatic interaction between grains, which might have played a great role in the enhancement of the maximum magnetization of the doped samples. The dielectric constant and loss tangent were evaluated as a function of frequency at room temperature. The photocatalytic activities of all the samples were evaluated by measuring the degradation of RhB dye under sunlight irradiation. The highest photocatalytic degradation efficiency of 94% was achieved with the substitution of Cr3+ (3%) and Eu3+ (4%) ions in BiFeO3 nanoparticles.