Bi-phase multiferroic composites of NiFe2O4/Ba0.94Ca0.06Ti0.975Zr0.025O3 (BCTZ/NFO) were successfully fabricated by high-energy ball milling combined with heat treatment. X-ray diffraction patterns and Raman spectra confirmed the successful coexistence of BCTZ and NFO phases in the final composites, which had an average particle size of 50 nm. However, the number of large particles increased with the increased NFO concentration in the composites. Optical properties of the composites were also modified by the NFO content, where the absorption band tended to the visible region and band-gap energies (E g) decreased with the increase of NFO. Ferromagnetic and ferroelectric properties of the BCTZ/NFO composites were also tuned by NFO additive content. Both saturation magnetisation (M s) and remnant magnetisation (M r) increased with the increase of NFO content, where the maximum values of M s = 22.52 emu g−1 and M r = 1.48 emu g−1 for composites with 40% NFO concentration, while coercivity (H c) was maintained at about 60 Oe. Maximum polarisation (P max), remnant polarisation (P r), and coercive field (E c) values all increased with NFO concentration, with 10% NFO providing the highest P max (= 0.249 μC cm−2) and P r (= 0.116 μC cm−2) values, and 30% NFO providing the highest E c (= 1.720 kV cm−1) value with a maximum applied voltage of 1 kV. Therefore, the multiferroic properties of BCTZ/NFO composites could be enhanced with an appropriate concentration of NFO, which led to a wide range of practical applications in the advanced electronic device field.

Spinel lithium nickel aluminium ferrite nanoparticles (Li2–2x Ni x Al2x Fe2–2x O4), (x = 0.0, 0.4, and 0.5) were prepared through the low temperature solution combustion method. Urea is employed as a fuel for the burning process. The synthesised samples are subjected to thermal analysis, x-ray diffraction, Fourier transformation infrared, Fourier transformation Raman spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy, selected area electron diffraction, ultraviolet-visible light spectroscopy, and vibrating sample magnetometry techniques. The thermal analysis revealed a combustion reaction occurring at around 300 °C. The structural and morphology results confirmed the nanoparticle nature and required material composition. The structural, optical, and magnetic properties significantly change, all of the particle size, band gap, coercivity, remnant magnetisation, and squareness ratio revealed a decreasing trend, while the dislocation density, micro-strain, saturation magnetisation, and the magnetic moment revealed a reverse trend as increment of Al and Ni content. The obtained optical, and magnetic properties confirm that the prepared materials are optically active, and soft ferrite nanoparticles. The ease of preparation method, observed good optical and magnetic properties together with cheap and environmentally benign precursor’s sources make achieved nanoparticles as promising material for nonlinear optics, microwave devices, and memory recording and storage applications.

The effect of 1 MeV Au+ ion irradiations on the layer stability of the Fe3O4-based films grown epitaxially on MgO(001) substrates was investigated by Rutherford backscattering spectroscopy (RBS) and RBS-Channelling (RBS-C). The ion mixing effect leads to an appearance of the additional FeO x layer and a large enlargement of the thickness of the mixed (Fe,Mg,O) layer in the interfaces. Au+ ions were found to be implanted deeply in the MgO substrate. RBS-C experiments have confirmed that the heavy metallic ion irradiations induce a disorder in the crystalline lattice.

Photocatalysis is a promising solution for the degradation of dyes since this substance harms the environment. In addition, this process is environmentally friendly, especially while using low energy through visible light irradiation. In this study, Ni1-xVxFe2O4 nano-photocatalyst has been prepared using the sol-gel method. After freeze-drying and calcination processes, the sample was characterised using the techniques of x-ray diffraction (XRD), FTIR, UV–vis DR spectroscopy, TEM, and Particle Size Analyser (PSA). The XRD results indicated that a majority of the crystalline phase in this material prepared is NiFe2O4 spinel. Then, the grain size of this spinel is in the range of 20–32 nm. UV–vis DR spectroscopy analysis indicated that the bandgap energy of spinel Ni1-xVxFe2O4 (where x = 0.1–0.5) is 1.6, 1.8, and 2.0 eV, respectively. FTIR analysis explained that catalyst functions as the photocatalyst, and maintains the structure after the reaction. Furthermore, results of dye photodegradation indicated that Ni1-x V x Fe2O4 nanocatalysts are all active and able to degrade remazol golden yellow (RGY) by more than 30% conversion under the visible light irradiation. In two stages of experiments to degrade RGY, Ni0.5V0.5Fe2O4 nanocatalyst has the best activity with more than 65% conversion. However, based on the linearity correlation in determining the order reaction, it is clear that the rate is a pseudo-first-order reaction and the best rate constant for reaction below 80 min, k = 0.0029 min−1 for Ni0.7V0.3Fe2O4 photocatalyst.

Minoxidil (Mxd) is a common medication used for hair regrowth in patients exhibiting different types of alopecia, especially androgenetic alopecia (AGA), but it has some negative aspects such as causing adverse effects and having limited permeation through the outer skin layers. In this study, minoxidil was encapsulated into niosomes and then loaded into chitosan nanoparticles and Aloe vera for creating a nanocomposite (Cs@Alo/Nio-Mxd), which will be used as a topical formulation to overcome these difficulties. The various prepared samples were physico-chemically characterised by their loading efficiency, TEM, SEM, zeta potential, FTIR and in vitro release profiles. The hair growth potential of the prepared formulations was evaluated by an in vivo study using rats with induced alopecia. Thirty-six rats with induced alopecia were randomised into six groups of six rats each. Group 1 (Negative control): rats served as normal and were treated with normal saline, Group 2: rats were treated with topical application of empty nanocomposites. Group 3 (Positive control): rats were treated with topical application of 5% Mxd, Group 4: rats were treated with topical application of (Cs-Mxd NPs), Group 5: rats were treated with topical application of (Cs@Alo-Mxd NPs). Group 6: rats were treated with topical application of (Cs@Alo/Nio-Mxd) nanocomposite. All formulations were applied once daily for 21 days. The treated skin was observed, photographed, and its histological features were examined. Results specified that Cs@Alo/Nio-Mxd nanocomposite could be preferentially deposited into the hair follicles, causing a significant increase (p < 0.05) in skin thickness, total hair follicle number per field, hair follicle diameter, hypodermis hair follicle number and anagen induction percentage.

The semiconductor metal oxide CuO films have been fabricated using spin coating techniques. The prepared CuO thin films were annealed at different temperatures and characterized by an x-ray diffractometer, scanning electron microscope (SEM), energy-dispersive x-ray spectroscopy (EDS), FTIR, UV–vis, and fluorescence spectrometer. X-Ray diffraction (XRD) patterns revealed the polycrystalline nature of CuO with the monoclinic crystal structure. SEM analysis of CuO films endorsed the particle-like spherical shape structure. The CuO thin films have shown high optical absorption with a narrow bandgap. The band gap values were evaluated from Tauc’s plots and these values were found to be in the range of 1.63 to 1.72 eV. At an excitation of 325 nm, the CuO films display characteristic photoluminescence (PL) emission in the UV and visible regions. Furthermore, the CuO thin films show enhanced photocatalytic performance towards the degradation of organic dyes under visible light.

Alloy nanocrystals (NCs) provide access and control of the parameters for nanoscale engineering because their physical and optical properties depend on size, shape, and composition. Here, alloy CdS x Se1−x NCs with different shapes were synthesised via a one-pot method using cadmium acetate, sulfur, and selenium as precursors in trioctylphosphine solution. The luminescence and shapes of NCs were characterised by fluorescence spectroscopy and transmission electron microscopy, respectively. It was found that the modification of precursor concentration resulted in NC shape variation, including branched NCs, long and short nanorods. Consequently, a series of alloy CdS x Se1−x NCs with different shape-based light emitting devices (LEDs) were fabricated and their operation characteristics were also compared. The obtained luminance and luminous efficiency showed that the control of NC shape is the key factor for the improvement of LED performance. We anticipate that this work will provide further insight into the design of CdSxSe1−x NCs-based LEDs with shape variation.

In the present study, the effect of annealing and Ar-plasma treatment on structural, morphological and optical properties of thermally evaporated β-In2S3 thin films has been investigated. During Ar-plasma treatment, some interesting results were observed that an array of metallic indium nanostructures was formed over In2S3 film surface with quasi-spherical or spread droplet shapes of an average size of 20–100 nm in the lateral direction and a height of less than 70 nm. Here, the Ar-plasma treatment serves as a new strategy for the self-formation of metallic indium nanostructures over the film surface. Further, the optical absorption of In2S3 films has been enhanced from 104 to 107 cm−1 while the optical band gap energy decreased from 2.71 eV to 2.50 eV after Ar-plasma treatment. The metallic nanostructures loaded on semiconductor surface can act as an electron trap that can effectively prevent the recombination of photo-generated electron-hole pairs.

In this study, the feasibility of the production of electrospun nanofibre composite mainly for biomedical applications is reported. Biocompatible polyether-based polyurethane, natural proteinaceous polymer silk sericin (SS) and natural inorganic nanoclay halloysite as a drug carrier with a model drug chlorhexidine acetate were used to produce nanofibres by electrospinning technique. Sericin was extracted from Bombyx mori silk cocoons by high pressure high temperature (HT-HP) degumming. Chlorhexidine acetate (CA), an antimicrobial agent, was loaded into halloysite nanotubes (HNTs) at different weight ratios, and 1:1 weight ratio showed the maximum loading which was confirmed by TGA and XRD analysis. Electrospinning of polymer solution with different compositions of polyurethane, sericin, CA and CA-HNTs was conducted at 10% w/v concentration, 20 kV voltage, 15 μl min−1 flow rate and 10 cm distance which resulted in the formation of bead-free uniform fibres. Antimicrobial activity of nanofibrous webs was evaluated by the disc diffusion method (AATCC 90) and it was found that CA and CA-HNT loaded nanofibres show sustained antibacterial action against both the Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. The CA-HNT and sericin/CA-HNT loaded nanofibres showed controlled release of CA. In addition, the cytocompatibility assessment of developed nanofibrous composites showed good biocompatibility. Hence the produced composite nanofibre can serve as an excellent material for sustained drug release for various biomedical applications.

In this study, electrospun polyurethane nanofibre composite incorporated with drug loaded halloysite nanotubes is presented. Chlorhexidine acetate (CA) drug was loaded into the halloysite nanotubes (HNT) to facilitate its controlled release for prolonged efficacy. The drug loading percentage in HNT was determined using thermo-gravimetric (TG) analysis. Uniform fibrous webs were obtained by electrospinning technique with optimised process parameters (i.e., 10 KV, flow rate of 5 μl min−1 and needle to collector distance of 10 cm) which was evident from SEM images. Antimicrobial efficiency of the nanowebs was determined using disk diffusion method (AATCC 90) against both the Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. The polyurethane/HNT-CA nanowebs showed very good activity against these strains. The drug release analysis of the nanowebs was carried by UV–vis spectrophotometry using total immersion method. The nanocomposite with drug loaded in HNT showed higher controlled release characteristics as evident from the drug release assay.

As-prepared samples of La1.5Sr0.5NiO4 (LSNO) and BaTiO3 (BTO) were prepared by ball milling method combined with heat treatment. X-ray diffraction analysis showed the pure phases of LSNO with a tetragonal structure and BTO with a cubic structure. Average crystalline sizes were 15 and 35 nm for the LSNO and BTO samples, respectively. Lattice parameters ​​of LSNO and BTO were almost unchanged after compositing, indicating no diffusion or chemical reaction between them during the compositing process. Adding LSNO to the BTO-based material significantly improved the ferroelectric and ferromagnetic properties, contributing to the enhancement of the electrical polarisation of the composites. These enhancements also boosted the microwave absorption performance of the composites. In detail, 20LSNO/80BTO nanocomposite embedded in acrylic paint could achieve the reflection loss up to −27 dB, meaning 99.8% of the incident microwave being absorbed. This absorber could also reach absorptivity over 60% for almost the whole range of the K u band frequency, which proved that 20LSNO/80BTO nanocomposite could be used as a good microwave absorber for practical applications.

Co-doping is an effective strategy to optimise the photovoltaic performance of GQDs. However, due to the heterogeneity of GQDs, it is difficult to achieve controllable photovoltaic performance without determining the structure-property relationship. In this work, we perform first-principles calculations to investigate the optoelectronic properties of GQDs doped with S, B, and P atoms. Our results show that S doping is crucial for tuning the photoelectric performance of S,B and S,P co-doped GQDs. Increasing the polarity of the solvent improves the charge transfer performance of single P-doped GQDs. Moreover, single P-doped GQDs show better photovoltaic performance than other doping configurations. Furthermore, the addition of B co-dopants to GQDs with Sh doping configuration improves the energy conversion of GQDs compared to B doping alone. Our study provides guidance for the rational design of GQDs for various photovoltaic applications.

A fluorescent system formed by the combination of coumarin derivative and self-assembled peptide nanostructures was used as sensing system to determine dissolved oxygen (O2) in water samples. Detection was based on the sensing system fluorescence quenching by O2, measured by steady-state and time-resolved fluorescence spectroscopy and Stern-Volmer plot to correlate fluorescence intensity to O2 concentration in the samples. Also, fluorescence lifetime decays informed about the mechanisms in which the quenching is occurring, indicating that the sensing system is highly sensitive and selective to O2, since quenching occurs by a non-radiative energy transfer from electronic excited singlet states of the system to the O2 molecule. This process was evidenced by the system fluorescence lifetime decrease, yielding Singlet O2 as indicative that this system can also find other technological applications.

Environmental pollution, in particular, the wastewater from the textile and dyeing production process is causing serious issues for the ecosystem and humans. It has been well-demonstrated that zero-valent iron nanoparticles (nZVI) are one of the most promising materials in the treatment of environmental pollutants. In this work, the Cleistocalyx operculatus leaf extract was employed as a green reductant for the synthesis of the nZVIs nanoparticles from iron ions precursor. Notably, a microfluidic device was also used as micro-reactor for the synthesis process of the nanoparticles, making it easy to control and optimise the morphologies and sizes of nZVI. The morphology and crystallinity of nZVI were characterised by scanning electron microscopy (SEM) and x-ray diffraction (XRD), respectively. The nZVIs prepared in a microfluidic reactor using Cleistocalyx operculatus leaf extract as reductant were in plate-like structure with the thickness of around 5 nm and the diameter in range of hundred nanometers. The removal efficiency of Rhodamin B (RhB) dye by the prepared nZVI was determined by ultraviolet-visible (UV–vis) spectroscopy. The results showed that the nZVI revealed high removal performance toward RhB with removal efficiency of higher than 90% after 30 min of treatment. The effects of dye’s concentration, time, and pH solution on the treatment performance of RhB were also studied.

The dextran-coated superparamagnetic iron oxide nanoparticles (SPIONs) grafted with foliate (FA) were prepared and used as a nanocarrier for ellipticine (ET) delivery in cervical cancer. In this work we prepared superparamagnetic iron oxide nanoparticles by pulsed laser ablation in liquid method. The formation of the SPION@DEX-ET-FA nanosystem was performed by a reverse microemulsion process. Dynamic light scattering (DLS), atomic force microscopy (AFM), and field emission scanning electron microscope (FESEM) were used to characteristic the morphological properties of the NPs. The appropriate impact of a therapeutic dose of SPION@DEX-ET-FA on both cancer and healthy cell lines was estimated using a 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) assay. The flow cytometry assays was used to evaluate the induction of apoptosis in Hela cervical cancer cells. The findings of the SPION@DEX-ET-FA formulated were spherical particles with an average size, polydispersity and a zeta potential of 101 ± 15.02 nm, 0.075 and −33.8 mV, respectively. The nanosystem displayed dose-dependent cytotoxic effects on Hela cells. The results showed that SPION@DEX-ET-FA retained antitumor activity and no adverse effects on healthy cells were found.

In recent era, green trend of synthesising biogenic nanoparticles (NPs) is a sustainable, safe, environment-friendly, and relatively inexpensive substitute to conservative routes of NPs making. Biosynthesis route showcases significant properties such as the absence of poisonous chemical compounds used as stabilising or reducing agents, lack of toxic yields generated from the process, reduced energy consumption, inexpensiveness, and high scalability. This has made green synthesis methods more attractive than other traditional methods. Synthesis of nanomaterials (NMs) using algae extracts is a substantiating ecological, simple, low-priced biosynthesis process. The secondary metabolites from algae have been reported to reduce metal precursors to nanoparticles (metal, metal oxide, or bimetallic NPs). Moreover, they cap and stabilise. Depending on the site of NP formation, synthesis could occur intra or extra-cellularly. Among the varied series of algae mediated synthesis, the most commonly biosynthesised NPs are silver, gold, copper oxide, cuprous oxide and zinc oxide. The algal biosynthesised NPs have been reviewed for numerous biomedical applications, which comprise anti-cancerous, anti-fouling, anti-bacterial, anti-fungal, bioremediation, and biosensing activities. The current review draws the major stress on the basis behind the algal-mediated biosynthesis of metallic and metallic oxide NPs from various algae. Furthermore, special attention to critical understanding of biosynthesis mechanism of NPs from algae and their biomedical applications has been reviewed critically.

In this work structural, magnetic and antimicrobial studies of gadolinium (Gd) doped cobalt ferrite nanopowder samples were synthesised through facile auto-combustion route using citric acid as combustion agent. The pristine nanopowders were sintered at 600 °C. X-ray diffraction (XRD), infrared spectroscopy (IR) measurements indicated the formation of a single spinel phase. The lattice constant gradually increased from 8.3801 Å to 8.3915 Å with increasing Gd concentration. The average crystallite size varied from 54 nm to 42.7 nm. The correlation between the cation distribution from XRD and the magnetic properties is discussed. The substitution of Gd ions significantly reduced the magnetisation from 60.6 to 36.6 emu g−1 and increased the coercivity. Antimicrobial activities of pure and Gd substituted cobalt ferrite are carried out against Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and also against fungi strain (Aspergillus niger) pathogens, suggesting that Gd substitution significantly improves the activity of cobalt ferrite nanopowders.

Carbon nano-onions (CNO) are versatile carbon nanomaterials with many potential biomedical applications. In this work, the interaction of submerged arc discharge in water (SADW) produced CNOs with the neutral red (NR) dye was studied. This dye is used in the in vitro toxicity NR assay, one of the most commonly used dye-based procedures to determine cell viability. Firstly the NR assay was carried out in murine fibroblast cell cultures exposed to CNOs. It was demonstrated that this assay produced invalid results due to the strong adsorption of NR on the CNOs. Fourier transform infrared spectroscopy (FTIR) and x-ray photoelectron spectroscopy (XPS) studies confirmed the effective adsorption of the NR on CNOs and π-π stacking as the main interaction between them. The adsorption of NR on the CNOs was evaluated by studying the decrease of the dye solution absorbance. The influence of different experimental conditions such as pH and CNOs dosage was evaluated: absorbance was found to diminish with the CNO dosage. For the maximum dosage used of 240 μg ml−1, the highest absorbance drops of −85% at pH 7 and −78% at pH 4 were registered. The adsorption process was found to be described best by a pseudo-first order (PFO) kinetics model (R 2 = 0.99), with a kinetic adsorption constant of k 1 = 0.02 min−1 and achieving an estimated sorption capacity of 3866 mg of dye per gram of CNOs. This is one of the highest values ever reported for dyes’ adsorption on carbon materials. Lastly, density functional theory (DFT) calculations were carried out to gain further insights into the interaction. These studies suggest a CNO highest occupied molecular orbital (HOMO)/NR lowest unoccupied molecular orbital (LUMO) electron density transfer as the main orbital interaction.

This work presents a successful and novel method for the preparation of Nb2O5 nanoparticles via pulsed laser ablation in liquid (PLAL) by employing a pure Nb plate and deionised water. The effect of various laser fluences on the chemical, structural, morphological and optical characteristics was studied. Chemical characteristics confirmed the formation of the orthorhombic T-Nb2O5 structure. While the morphology characteristics showed spherical particles and its density dependency on the laser fluence. The Nb2O5 stoichiometry ranged between 42.20% and 88.86%. Additionally, the structural analysis showed peaks related to the orthorhombic T-Nb2O5 structure with grain size between 58.2 and 244.6 nm. Lastly, topographical images showed that the average particle size was in the range 6.8 and 32 nm, and sample roughness was between 17.39 and 1.377 nm.

This research studied the effects of different laser energies on structural and optical properties. We prepared CdTe thin films by PLD technique using an Nd:YAG laser with a wavelength of 1064 nm and different energies (400, 500, 600, and 700 mJ). The practical experiments were carried out at a temperature of 200 °C. XRD results revealed that all the prepared thin films have polycrystalline structures and cubic systems with average crystalline sizes of 34, 42, 54, and 57 nm for 400, 500, 600, and 700 mJ, respectively. We observed that the optical energy gap of CdTe thin films decreases with the increase of laser energy (1.87–1.58 eV). The topography of the surfaces of CdTe thin films deposited on glass substrates was studied by the AFM technique, and it was shown that the average diameter of all CdTe films increases with increasing laser energies. The mentioned properties were studied for the application of this thin film as the absorber layer in constructing a solar cell.