Microwave-assisted Synthesis Method Research Articles

Microwave synthesized erbium vanadate nano-photocatalyst: Application for enhanced degradation of contaminated water

The subject of treatment of real or synthetic industrial effluents and photocatalysts has concerned a lot of consideration from scientists. Among the diverse metal oxide photocatalytic materials, the narrow bandgap compounds are of superior significance owing to appropriate efficiency in the optical application. In this work, we produced pristine ErVO4 through the microwave-assisted synthesis method. Diverse solvents and different power intensities have been employed in this preparation for size controlling and shape engineering, such as Ethylene glycol (EG), Propylene glycol (PG), and Polyethylene glycol (PEG-400) and power of 900, 750 and 600 W. XRD, FT-IR, and EDS analysis have been utilized to demonstrate the phase purity, and FE-SEM and TEM were employed to discover the shape of resultant ErVO4. The several attributes of the samples, such as the surface area, magnetic and optical features, were inquired by BET, VSM and DRS techniques, correspondingly. Microwave power of 900 W and Ethylene glycol solvent was selected as an optimal condition owing to the creation of uniform nanosized particles. So nanostructured ErVO4 was operated as a catalyst for the decolorization of colored pollutants (Erythrosine (ER), Methyl Orange (MO), and methylene blue (MB)). According to the discoveries, the MB with higher photocatalytic efficiency was compared in different dye concentrations and catalyst loading experiments to attain ideal performance.

Rational synthesis of silane-functionalized carbon dots with high-efficiency full-color solid-state fluorescence for light emitting diodes

Highly efficient full-color solid-state fluorescent carbon dots (CDs) are very critical for the construction of light-emitting diodes (LEDs), especially white light-emitting diodes (WLEDs), but achieving them is still a challenging task due to the serious self-quenching of CDs in the aggregation state and their complicated photoluminescence (PL) mechanism. Herein, we reported a one-step microwave-assisted method for the large-scale synthesis of solid-state silane-functionalized CDs (SiCDs) with self-quenching resistant and tunable full-color fluorescence. By only controlling the ratio of precursors, the PL emission of these SiCDs can be tuned in the visible region ranging from 438 to 633 nm, accompanied by high quantum yields (QYs) of up to 26-57%. The multicolor emission of these SiCDs is ascribed to their differences in particle size and graphitic nitrogen content, which can be modulated by controlling the dehydration and condensation reactions among raw materials. In addition, based on their excellent optical properties, these SiCDs were directly utilized as phosphors combing with ultraviolet chips to prepare full-color LEDs and all types of WLEDs with adjustable correlated color temperature (CCT) from 3678 to 8158 K and high color rendering index (CRI) of 90–94, demonstrating the tremendous potential for practical lighting applications.

Optimization Temperature Programming of Microwave-Assisted Synthesis ZnO Nanoneedle Arrays for Optical and Surface-Enhanced Raman Scattering Applications.

This study used a rapid and simple microwave-assisted synthesis method to grow ZnO nanoneedle arrays on the silicon substrate with the ZnO seed layer. The effects of reaction temperature and time on the lengths of ZnO nanoneedle arrays were investigated. The appropriate temperature programming step can grow the longer ZnO nanoneedle arrays at the same reaction time (25 min), which is 2.08 times higher than without the temperature programming step. The geometry of the ZnO nanoneedle arrays features a gradual decrease from the Si substrate to the surface, which provides an excellent progressive refractive index between Si and air, resulting in excellent antireflection properties over an extensive wavelength range. In addition, the ZnO nanoneedle arrays exhibit a suitable structure for uniform deposition of Ag nanoparticles, which can provide three-dimensional hot spots and surface active sites, resulting in higher surface-enhanced Raman scattering (SERS) enhancement, high uniformity, high reusability, and low detection limit for R6G molecule. The ZnO/Ag nanoneedle arrays can also reveal a superior SERS-active substrate detecting amoxicillin (10-8 M). These results are promising for applying the SERS technique for rapid low-concentration determination in different fields.

Rapid Microwave-Assisted Synthesis of N/TiO2/rGO Nanoparticles for the Photocatalytic Degradation of Pharmaceuticals.

Nanocomposites comprising nitrogen-doped TiO2 and reduced graphene oxide (N/TiO2/rGO), with different rGO loading qualities, were prepared by a cost-effective microwave-assisted synthesis method. The synthesized materials were broadly characterized by Raman spectroscopy, X-ray diffraction (XRD), infrared spectroscopy (FTIR), photoelectron spectroscopy (XPS), diffuse reflectance spectroscopy (DRS), electron microscopy (SEM-EDS), and nitrogen adsorption/desorption isotherms. Anatase was the only crystalline phase observed for all synthesized materials. The rGO loading did not affect the morphological properties, but it positively influenced the photocatalytic activity of the nanocomposite materials, especially at low rGO loading. Photocatalysts were evaluated via the degradation of specific organic micropollutant (OMP) pharmaceuticals: ciprofloxacin (CIP), diclofenac (DCF), and salicylic acid (SA), under different radiation sources: ultraviolet A (UVA), solar light simulator (SLS), blue visible light (BVL) and cold visible light (CVL). CIP and SA were removed effectively via the synergy of adsorption and photocatalysis, while DCF degradation was achieved solely by photocatalysis. After implementing scavenger agents, photocatalytic degradation processes mainly depended on the specific pollutant type, while irradiation sources barely defined the photocatalytic mechanism. On the other hand, changes in irradiation intensity significantly influenced the photolysis process, while photocatalysis was slightly affected, indicating that irradiation spectra are more relevant than intensity.

Microwave-assisted synthesis of l-aspartic acid-based metal organic aerogel (MOA) for efficient removal of oxytetracycline from aqueous solution

Developing advanced adsorption materials is of great significance for removing antibiotics from wastewater owing to the increasingly severe issue of antibiotic contamination. Herein, a novel bio-based metal organic aerogel (FLAM) adsorbent with macroscopic shapeability, formed through the coordination of l-aspartic acid (L-AA) and Fe salt, was fabricated for the first time via the microwave-assisted synthesis method. Subsequently, the FLAM was used to remove oxytetracycline (OTC) from aqueous solution, and the result indicated FLAM exhibited ultrahigh adsorption capacity for OTC with a record-high value of 1566 mg·g−1, which greatly outperformed the reported adsorbents. The adsorption equilibrium curve and adsorption thermodynamics followed the pseudo-second-order kinetics model and the Freundlich model respectively, which indicated multilayer adsorption and chemisorption dominated the adsorption process. Significantly, the adsorbent also enabled efficient decontamination of tetracycline (TC) and chlortetracycline hydrochloride (CTC). Such an excellent adsorption capability of FLAM can be attributed to multiple factors, i.e., electrostatic interaction, surface complexation and hydrogen bonding. Coexisting experiments demonstrated that the FLAM possessed excellent application ability in treating practical antibiotic wastewater. Ultrahigh adsorption capacity and fast-synthesis method prefigured its broad prospect for OTC-related wastewater remediation.

Light-Activated Modified Arginine Carbon Dots as Antibacterial Particles

Nitrogen-doped arginine carbon dots (Arg CDs) as light-sensitive antibacterial agents were prepared by using citric acid as the carbon source and arginine amino acid as the nitrogen source via a microwave-assisted synthesis method. Dynamic light scattering (DLS) measurements and TEM images revealed that the Arg CDs were in the 1–10 nm size range with a graphitic structure. To improve their antibacterial capability, the Arg CDs were modified with ethyleneimine (EDA), pentaethylenehexamine (PEHA), and polyethyleneimine (PEI) as different amine sources, and the zeta potential value of +2.8 ± 0.6 mV for Arg CDs was increased to +34.4 ± 4.1 mV for PEI-modified Arg CDs. The fluorescence intensity of the Arg CDs was significantly enhanced after the modification with EDA, and the highest antibacterial effect was observed for the PEI-modified Arg CDs. Furthermore, the photodynamic antibacterial capacity of bare and EDA-modified Arg CDs was determined upon light exposure to show their light-induced antibacterial effects. Photoexcited (315–400 nm, UVA, 300 W), EDA-modified Arg CDs at 5 mg/mL concentration were found to inhibit about 49 ± 7% of pathogenic bacteria, e.g., Escherichia coli, with 5 min of light exposure. Furthermore, the biocompatibilities of the bare and modified Arg CDs were also investigated with blood compatibility tests via hemolysis and blood clotting assays and cytotoxicity analysis on L929 fibroblast cells.

Photoreactive Carbon Dots Modified g-C3N4 for Effective Photooxidation of Bisphenol-A under Visible Light Irradiation

A series of carbon dots (CDs) modified g-C3N4 (xCDs/g-C3N4; x = 0.5, 1.0, and 1.5 mL CDs solution) was synthesized via the microwave-assisted hydrothermal synthesis method for the photooxidation of bisphenol-A (BPA) under visible light irradiation. The X-ray diffraction (XRD) analysis indicates that the CDs may have a turbostratic structure and the resulting photocatalysts have distorted crystal structure, as compared with pure g-C3N4. The high-resolution transmission electron microscope (HR-TEM) analysis revealed amorphous, mono-disperse, spherical CDs with an average particle size of 3.75 nm. The distribution of CDs within the matrix of g-C3N4 appear as small dark dot-like domains. The N2 adsorption-desorption analysis indicates that the nanocomposites are mesoporous with a density functional theory (DFT) estimate of the pore size distribution between 2–13 nm. The CDs quantum yield (QY) was determined to be 12% using the UV-vis spectral analysis, where the CDs/g-C3N4 has improved absorption in the visible region than g-C3N4. The higher BET surface area of CDs/g-C3N4 provided more adsorption sites and the ability to yield photogenerated e−/h+ pairs, which caused the 1.5 CDs/g-C3N4 to have better photocatalytic efficiency compared to the rest of the systems. The highest removal, 90%, was achieved at the following optimum conditions: BPA initial concentration = 20 mg L−1, catalyst dosage = 30 mg L−1, and pH = 10. The photooxidation process is mainly driven by photogenerated holes (h+) followed by •OH and O2•−. The synthesis of the 1.5 CDs/g-C3N4 system is simple and cost-effective, where this photocatalyst is highly stable and reusable versus other systems reported in the literature.

Multifunctional Smart ZnSe-Nanostructure-Based Fluorescent Aptasensor for the Detection of Ochratoxin A.

Herein, we present a comprehensive investigation of rationally designed zinc selenide (ZnSe) nanostructures to achieve highly negatively charged ZnSe nanostructures. A Microwave-assisted hydrothermal synthesis method was used to synthesize three types of ZnSe nanostructures, i.e., nanorods, µ-spheres and nanoclusters, as characterized by a zeta potential analyzer, X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and BET, which were labeled as type A, B and C. Three different solvents were used for the synthesis of type A, B and C ZnSe nanostructures, keeping other synthesis conditions such as temperature, pressure and precursors ratio constant. Based on two heating time intervals, 6 and 9 h, types A, B and C were further divided into types A6, A9, B6, B9, C6 and C9. ZnSe nanostructures were further evaluated based on their fluorescent quenching efficiency. The maximum fluorescence quenching effect was exhibited by the ZnSe-B6 type, which can be attributed to its highly negative surface charge that favored its strong interaction with cationic dye Rhodamine B (Rh-B). Further, the optimized ZnSe-B6 was used to fabricate an aptasensor for the detection of a food-based toxin, ochratoxin-A (OTA). The developed aptasensor exhibited a limit of detection of 0.07 ng/L with a wide linear range of 0.1 to 200 ng/L.

Phenyl substituted 3-chloro 2-azetidinones: Design, green synthesis, antimicrobial activity, and molecular docking studies

In the present study, by applying an effective microwave-assisted synthesis method for some new phenyl substituted 3-chloro 2-azetidinone derivatives, starting with methyl 2-(4-amino-3-iodophenyl)acetate were synthesized with excellent yield and in-vitro screening for antimicrobial activity. The microwave synthesis offers a shorter reaction time (20-45 min), moderate reaction conditions, high returns (81%-96%), and easier operation than conventional heating. Spectroscopic techniques like 1H NMR, LCMS, IR, and 13C NMR analysis have been used to examine the structure of the newly synthesized compounds. All newly synthesized β-lactam derivatives (8a-h) were tested for antimicrobial activity against diverse bacterial and fungus strains using the broth dilution technique. Most of the investigated substances showed promising effectiveness against bacterial and fungal strains, with values ranging from 0.78 to 50 µg/mL. In contrast to the standard Ciprofloxacin for antibacterial activity and Ketoconazole for antifungal activity, compound 8c demonstrated good robust antibacterial activity against Escherichia coli and antifungal activity against Aspergillus niger with a value of 0.78 µg/mL of concentration. The final targets were performed to the inhibition of DNA gyrase by molecular docking experiments to acquire insight into relevant proteins. The results of silico molecular docks coincide with the in vitro antimicrobial investigations and may be regarded as a good DNA gyrase inhibitor.

Energy transfer mechanism of Eu2+, Mn2+Doped lithium aluminate phosphor: Synthesis, Hirshfeld surface analysis and optical study

The LiAlO2 phosphor doped with Eu2+ sensitizer ions and Mn2+ ions activator were synthesized by employing microwave-assisted solution combustion synthesis method (SCS), and structural correlation investigations were elaborated. The host material was characterized by XRD, FT-IR, SEM, TEM analysis and their spectroscopic studies by photoluminescence study. The structural correlation i.e., 3D Hirshfeld surface analysis and 2D fingerprint plots of the LiAlO2 phosphor were generated using crystal explorer-17 software in order to discuss strength of different bonds and their inter-contacts. The energy transfer from Eu2+ to Mn2+ ions through exchange interactions was explained by Dexter's exchange interactions. The energy transfer interactions are possibly due to dipole-dipole transitions was best demonstrated by linear fitting with n: 6 (R2 = 0.987). The chromaticity diagram explains the nature of the color spectrum of phosphor-based on their particular wavelengths. The energy transfer from Eu2+ ions to Mn2+ ions leads to wavelength tunable ability of the phosphor suitable for the development of warm white light LEDs.

Surface functionality as a key parameter for the conductivity of microwave synthesized CQDs thin films

The carbon quantum dots (CQDs) as zero-dimensional carbon nanomaterials with extraordinary physicochemical properties have a broad range of applications. Some of the most intriguing is the CQD thin films for electronic devices and membrane nanofiltration. Here we present the simple and affordable microwave-assisted synthesis method for the production of the nitrogen-doped CQDs (N-CQD) and iron/nitrogen co-doped CQDs (FeN-CQD). The comprehensive study of the morphology and electrical properties of N-CQD and FeN-CQD was discussed after manufacturing obtained nanomaterials in the form of a thin film on different substrates using different deposition procedures. The morphological features of generated thin films altered dramatically when the substrate and nanomaterial properties, as well as the number of deposited layers of CQDs and the chosen deposition process, were taken into consideration.

Comparison of synthesis methods of Tb MOF: microwave and metathesis

This paper presents the synthesis of the metal-organic structure of terbium Tb2(BDC)3 (BDC: 1,4-benzendicarboxylic acid) obtained by stirring at room temperature (SRT) and by means of the microwave-assisted synthesis method (MW) at 150 °C during 15 min. A comparison was made between the physicochemical properties of the MOF obtained by each of the methods as they were characterized by powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR), observing crystalline materials with crystal size 66.42 and 26.57 nm for SRT and MW, respectively. The luminescent properties were determined by photoluminescent spectroscopy (FL) and finally the morphology presented by MW synthesis.

Conventional vs. Microwave-assisted Synthesis: A Comparative Study on The Synthesis of Tri-substituted imidazoles

Background: The organic and peptide synthesis, various nanotechnology, and biochemistry processes are being carried out using microwave irradiation. The use of microwaves for synthesis has increased in the past two decades. The microwave offers several advantages such as ease of handling, lesser reaction times, quality of the product, and eco-friendly, which is green. The conventional method of synthesis, on the other hand, requires a longer time, is difficult to handle and maintenance of temperature is also difficult. The use of microwave-assisted reactions over conventional methods is advantageous in medicinal chemistry research as they will be less time-consuming and crucial in drug discovery and development. On the other side, they might not work in bulk synthesis due to their limited capacity for loading the reaction mixture. Objective: The present work aims to compare reaction time, temperature and percentage of yield of the microwave-assisted synthesis method against the conventional method. Method: A novel, simple, and green method was developed for the synthesis of tri-substituted imidazoles by microwave irradiation. Both derivatives from conventional and microwave-assisted synthesis were characterized by IR spectroscopy, Mass spectrometry, and 1H-NMR spectroscopy. The same derivatives were also synthesized by the conventional method for comparison. Result: A comparison of both methods was made by comparing the reaction time and the percentage yield. It was found that microwave-assisted reactions produced greater yield in the minimal time, though at different reaction temperatures. Conclusion: It can be concluded from the present comparison study that the use of the microwave for synthesis provides numerous advantages; thus, newer molecules are developed quickly anthat are developed quickly. To further proceed in this direction and to produce evidences, synthesis of more derivatives may be required. The only disadvantage is that it cannot be used for bulk synthesis of the compounds.

Aflatoxin B1 Acts as an Effective Energy Donor to Enhance Fluorescence of Yellow Emissive Carbon Dots.

Carbon dots (CDs) are versatile fluorescent nanocrystals with unique optical and structural properties and are commonly used in biosensing, bioimaging, and biomolecule tagging studies. However, fluorescence of CDs is brightest in the wavelength range of 430–530 nm, which overlaps with the autofluorescence range of many eukaryotic cells and makes CDs impractical for in vivo and in vitro imaging studies. Thus, the design of yellow-red emissive CDs with high quantum yield is of importance. In this study, the quantum yield of traditional yellow emissive CDs was enhanced by two different methods: (1) the surface of traditional yellow emissive CDs passivated with a biomolecule, urea, through easy, rapid, inexpensive microwave assisted synthesis methods and (2) a fluorescent biomolecule, aflatoxin B1, used as an energy donor for yellow emissive CDs. In the first method, the quantum yield of the CDs was enhanced to 51%. In the second method, an efficient energy transfer (above 40%) from aflatoxin B1 to the CDs was observed. Our study showed that highly luminescent yellow emissive CDs can be synthesized by simple, rapid microwave assisted synthesis methods, and these CDs are potential candidates to sense aflatoxin B1. Furthermore, our results indicated that Aflatoxin B1 can be considered as an emission booster for CDs.

Microwave-Assisted Solvothermal Synthesis of Nanocrystallite-Derived Magnetite Spheres.

The synthesis of magnetic particles triggers the interest of many scientists due to their relevant properties and wide range of applications in the catalysis, nanomedicine, biosensing and magnetic separation fields. A fast synthesis of iron oxide magnetic particles using an eco-friendly and facile microwave-assisted solvothermal method is presented in this study. Submicron Fe3O4 spheres were prepared using FeCl3 as an iron source, ethylene glycol as a solvent and reductor and sodium acetate as a precipitating and nucleating agent. The influence of the presence of polyethylene glycol as an additional reductor and heat absorbent was also evaluated. We reduce the synthesis time to 1 min by increasing the reaction temperature using the microwave-assisted solvothermal synthesis method under pressure or by adding PEG at lower temperatures. The obtained magnetite spheres are 200–300 nm in size and are composed of 10–30 nm sized crystallites. The synthesized particles were investigated using the XRD, TGA, pulsed-field magnetometry, Raman and FTIR methods. It was determined that adding PEG results in spheres with mixed magnetite and maghemite compositions, and the synthesis time increases the size of the crystallites. The presented results provide insights into the microwave-assisted solvothermal synthesis method and ensure a fast route to obtaining spherical magnetic particles composed of different sized nanocrystallites.

Green synthesized silver nanoparticles with mushroom extracts of Paxina leucomelas and Rhizopogon luteolus induce ROS-Induced intrinsic apoptotic pathway in cancer cells

The green synthesized silver nanoparticles (AgNPs) provide many advantages including the production of nanoparticles without using toxic compounds and solvents, the low-cost of the synthesis process, the existence of a large number of biological substances as a reducing agent of silver, and the production of nanoparticles in desired parameters. In this study, the PL-AgNPs and RL-AgNPs were synthesized by microwave-assisted green synthesis method using extracts of Paxina leucomelas and Rhizopon luteolus. The synthesized P. leucomelas-AgNPs (PL-AgNPs) and R. luteolus-AgNPs (RL-AgNPs) were characterized by UV–Vis, FTIR, XRD, DLS, S-TEM, and EDS analysis. Anticancer activity of the synthesized AgNPs was investigated on human cancer cells lines. Obtained results demonstrated that the PL-AgNPs and RL-AgNPs decreased cancer cell viability via ROS-mediated intrinsic apoptotic pathways. These findings strongly suggest that the AgNPs formed by aqueous extracts of P. leucomelas and R. luteolus may be introduced as an alternative apoptosis inducer in cancer drug discovery.

TiO2 nanocomposite ceramics doped with silver nanoparticles for the photocatalytic degradation of methylene blue and antibacterial activity against Escherichia coli

The development of highly efficient and stable photocatalysts for wastewater treatment has been identified as one of the most important environmental challenges facing the world. In this study, titanium dioxide (TiO2) fibrous nanocomposites doped with novel silver nanoparticles (Ag NPs) were synthesized by combining sol–gel and electrospinning methods. For this aim, Ag NPs were fabricated via the microwave-assisted green synthesis method by using soluble starch as a reducing agent. The produced electrospun nanocomposites doped with Ag NPs were calcined at 700 °C for the decomposition of the polymer from the nanofiber structure and attain the anatase phase formation of TiO2. Also, pure TiO2 ceramic membrane was synthesized in the same way to compare the doping effect of Ag NPs on nanocomposite material. After the heat treatment process, Scanning electron microscopy (SEM), Energy-dispersive X-ray (EDX), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) techniques were utilized to characterize the morphological and structural properties of nanocomposite membranes. Different weight percentages of Ag NPs (2% and 2.5%) were used to investigate the effect of the Ag concentration on antimicrobial activity against Escherichia coli (E. coli), and the maximum antibacterial activity (99.999%) was achieved by TiO2 nanocomposite membrane doped with 2.5% Ag NPs. Based on the FTIR spectra, it was determined that the polymer was successfully removed by calcination at 700 °C. XRD, XPS and EDX results showed that Ag nanoparticles were incorporated and dispersed in TiO2 ceramic nanofibrous structure successfully. The photocatalytic ability of the nanofiber membranes was measured according to methylene blue (MB) concentration change in the aqueous solution under UV irradiation. The very high degradation rate of MB of 94.6% was reached with TiO2 nanocomposite membrane doped with 2.5% Ag NPs showing the synergistic effect of TiO2 and Ag NPs. The results indicate that Ag NPs–TiO2 nanocomposite membrane could efficiently degrade MB upon irradiation with UV light, showing greater photocatalytic activity and antibacterial activity than the pure TiO2 nanofibers.

A novel work function tuning strategy-based ECL sensor with sulfur dots and Au NP@MoS2 nanosheet heterostructure for triple-negative breast cancer diagnosis

In this work, a novel biosensor has been developed based on the sulfur dots and Au NP@MoS2 nanosheet heterostructure. On the one hand, highly luminescent sulfur dots were prepared by the microwave-assisted synthesis method as electrochemiluminescence (ECL) emitter. On the other hand, in order to regulate the ECL signal, Au NP@MoS2 nanosheet heterostructure has been constructed. In the heterostructure, the work function of 2-D MoS2 nanosheet with excellent electronic properties was relatively low than that of Au NPs. Due to the work function tuning strategy, there were local electrophilic or nucleophilic regions in the heterostructure. The resulted self-driven charge transfer at the interface further increased the local electron density of Au NPs. Therefore, the ECL quenching effect caused by the close-range electron transfer between the sulfur dots and the Au NPs has been effectively suppressed. And the localized surface plasmon resonance (LSPR) effect of Au NPs played a primary role to amplify the ECL signal of sulfur dots. Finally, the sensing system was designed for the detection of miRNA-210 from 0.1 pM to 10 nM. The ECL sensor showed good analytical performance in the detection of triple-negative breast cancer tumor and paracancerous tissues with the recoveries ranging from 91.7% to 102.4%. The satisfactory results indicated the work function tuning strategy-based sensor with sulfur dots and Au NP@MoS2 nanosheet heterostructure possessed great potential in the ECL research and clinical analysis.

Biological Activities and Biocompatibility Properties of Eu(OH)3 and Tb(OH)3 Nanorods: Evaluation for Wound Healing Applications.

Rare earth elements have shown promising results in both bio-imaging and therapy applications due to their superior magnetic, catalytic, and optical properties. In recent years, since lanthanide-based nanomaterials have effective results in wound healing, it has become necessary to investigate the different properties of these nanoparticles. The aim of this study is to investigate the antimicrobial, antibiofilm, and biocompability of Eu(OH)3 and Tb(OH)3 nanorods, which have a high potential by triggering angiogenesis and providing ROS activity, especially in wound healing. For this purpose, nanorods were obtained by the microwave-assisted synthesis method. Structural characterizations of Eu(OH)3 and Tb(OH)3 nanorods were performed by FT-IR, XRD, and TG-DTA methods, and morphological characterizations were performed by SEM-EDX. Microorganisms that are likely to be present in the wound environment were selected for the antimicrobial activities of the nanorods. The highest efficiency of nanorods with the disc diffusion method was shown against Pseudomonas aeruginosa ATCC 27,853 and Candida albicans ATCC 10,231 microorganisms. One of the problems frequently encountered in an infected wound environment is the formation of bacterial biofilm. Eu(OH)3 nanorods inhibited 77.5 ± 0.43% and Tb(OH)3 nanorods 76.16 ± 0.60% of Pseudomonas aeruginosa ATCC 27,853 biofilms. These results show promise for the development of biomaterials with superior properties by adding these nanorods to wound dressings that will be developed especially for wounds with microbial infection. Eu(OH)3 nanorods are more toxic than Tb(OH)3 nanorods on NCTC L929 cells. At concentrations of 500µg/ml and above, both nanorods are toxic to cells.

Achieving high thermoelectric performance through carrier concentration optimization and energy filtering in Cu3SbSe4-based materials

The previous works commonly adjust the carrier concentration through acceptor doping, but at the same time, the decrease of the Seebeck coefficient limits the further improvement of electrical properties in Cu3SbSe4-based materials. In this work, a microwave-assisted hydrothermal synthesis method was used to synthesize Cu3SbSe4/TiO2 hollow microspheres. Part of TiO2 participates in the reaction, replaces the Sb site of Cu3SbSe4 to form holes, and the rest is dispersed in the matrix in the form of the second phase. The first-principles calculations reveal that the doping of Ti significantly changes the band structure and phonon spectrum, thereby regulating carrier concentration while increasing phonon scattering. In addition, experimental results show that the energy filtering effect generated by the extra-mixed TiO2 nano particles, which suppresses the decrease of Seebeck coefficient by acceptor doping. Consequently, the highest average power factor 897.5 μW m−1 K−2 and the zT peak value of 0.70 can be obtained in Cu3SbSe4/6%TiO2 sample at 298–623 K. This work provides a new sight to improve the thermoelectric properties in Cu3SbSe4 through carrier concentration regulation and nano-phase composition.