Disentangling the Effects of Laser and Electron Irradiation on AgX (X = Cl, Br, and I): Insights from Quantum Chemical Calculations.

The effects on the lattice structure and electronic properties of different polymorphs of silver halide, AgX (X = Cl, Br, and I), induced by laser irradiation (LI) and electron irradiation (EI) are investigated using a first-principles approach, based on the electronic temperature (Te) within a two-temperature model (TTM) and by increasing the total number of electrons (Ne), respectively. Ab initio molecular dynamics (AIMD) simulations provide a clear visualization of how Te and Ne induce a structural and electronic transformation process during LI/EI. Our results reveal the diffusion processes of Ag and X ions, the amorphization of the AgX lattices, and a straightforward interpretation of the time evolution for the formation of Ag and X nanoclusters under high values of Te and Ne. Overall, the present work provides fine details of the underlying mechanism of LI/EI and promises to be a powerful toolbox for further cross-scale modeling of other semiconductors.

Isolated and combined effects of cobalt and nickel on the microalga Raphidocelis subcapitata.

Aquatic organisms are exposed to several compounds that occur in mixtures in the environment. Thus, it is important to investigate their impacts on organisms because these combined effects can be potentiated. Cobalt (Co) and nickel (Ni) are metals that occur in the environment and are used in human activities. To the best of our knowledge, there are no studies that investigated the combined effects of these metals on a freshwater Chlorophyceae. Therefore, this study analyzed the isolated and combined effects of Co and Ni in cell density, physiological and morphological parameters, reactive oxygen species (ROS), carbohydrates and photosynthetic parameters of the microalga Raphidocelis subcapitata. Data showed that Co affected the cell density from 0.25 mg Co L-1; the fluorescence of chlorophyll a (Chl a) (0.10 mg Co L-1); ROS production (0.50 mg Co L-1), total carbohydrates and efficiency of the oxygen evolving complex (OEC) at all tested concentrations; and the maximum quantum yield (ΦM) from 0.50 mg Co L-1. Ni exposure decreased ROS and cell density (0.35 mg Ni L-1); altered Chl a fluorescence and carbohydrates at all tested concentrations; and did not alter photosynthetic parameters. Regarding the Co-Ni mixtures, our data best fitted the concentration addition (CA) model and dose-ratio dependent (DR) deviation in which synergism was observed at low doses of Co and high doses of Ni and antagonism occurred at high doses of Co and low doses of Ni. The combined metals affected ROS production, carbohydrates, ΦM, OEC and morphological and physiological parameters.

Eco-friendly Synthesis of Silver Nanoparticles and its Application in Hydrogen Photogeneration and Nanoplasmonic Biosensing.

Environmentally friendly methods for silver nanoparticles (AgNPs) synthesis without the use of hazardous chemicals have recently drawn attention. In this work, AgNPs have been synthesized by microwave irradiation using only honey solutions or aqueous fresh pink radish extracts. The concentrations of honey, radish extract, AgNO3 and pH were varied. AgNPs presented mean sizes between 7.0 and 12.8 nm and were stable up to 120 days. The AgNPs were employed as co-catalyst (TiO2 @AgNPs) to increase the hydrogen photogeneration under UV-vis and only visible light irradiation, when compared to pristine TiO2 NPs. The prepared photocatalyst also showed hydrogen generation under visible light. Additionally, AgNPs were used to assemble a nanoplasmonic biosensor for the biodetection of extremely low concentrations of streptavidin, owing to its specific binding to biotin. It is shown here that green AgNPs are versatile nanomaterials, thus being potential candidates for hydrogen photogeneration and biosensing applications.

The Role of Zn Ions in the Structural, Surface, and Gas-Sensing Properties of SnO2:Zn Nanocrystals Synthesized via a Microwave-Assisted Route.

Although semiconducting metal oxide (SMOx) nanoparticles (NPs) have attracted attention as sensing materials, the methodologies available to synthesize them with desirable properties are quite limited and/or often require relatively high energy consumption. Thus, we report herein the processing of Zn-doped SnO2 NPs via a microwave-assisted nonaqueous route at a relatively low temperature (160 °C) and with a short treatment time (20 min). In addition, the effects of adding Zn in the structural, electronic, and gas-sensing properties of SnO2 NPs were investigated. X-ray diffraction and high-resolution transmission electron microscopy analyses revealed the single-phase of rutile SnO2, with an average crystal size of 7 nm. X-ray absorption near edge spectroscopy measurements revealed the homogenous incorporation of Zn ions into the SnO2 network. Gas sensing tests showed that Zn-doped SnO2 NPs were highly sensitive to sub-ppm levels of NO2 gas at 150 °C, with good recovery and stability even under ambient moisture. We observed an increase in the response of the Zn-doped sample of up to 100 times compared to the pristine one. This enhancement in the gas-sensing performance was linked to the Zn ions that provided more surface oxygen defects acting as active sites for the NO2 adsorption on the sensing material.

Cytotoxic Effects Caused by Functionalized Carbon Nanotube in Murine Macrophages.

BACKGROUND/AIMS: The development of new nanomaterials has been growing in recent decades to bring benefits in several areas, especially carbon-based nanoparticles, which have unique physical-chemical properties and allow to take on several applications. Consequently, the use of new nanomaterials without previous toxicological studies raises concern about possible harmful health effects. The aim of this study was to investigate the cytotoxic profile of a new multi-walled carbon nanotube (MWCNT) functionalized with tetraethylenepentamine called OCNT-TEPA using in vitro assays in murine macrophage cells linage J774 A.1. METHODS: OCNT-TEPA was characterized by transmission electron microscopy (TEM) and high resolution TEM (HR-TEM), scanning electron microscopy (SEM), zeta potential and dynamic light scattering (DLS), and its cytotoxic effects were evaluated at 24 and 48 hours by cell viability assays (MTT and NR), morphology and cell recovery (optic microscopy and clonogenic assay), formation of reactive oxygen (ROS) and nitric oxide (NO) species, inflammatory profile (IL-6 and TNF cytokines), mitochondrial membrane potential analysis (MMP), activation of the caspase 3 pathway and cell death (flow cytometry). RESULTS: The data showed a significant decrease in cell viability, increased production of ROS and NO, alteration of mitochondrial membrane potential, increased levels of inflammatory cytokines, alteration of cell morphology, activation of the Caspase 3 pathway and consequently cell death, in the highest concentrations of OCNT-TEPA tested in the periods of 24 and 48 hours. CONCLUSION: The analyses showed that OCNT-TEPA has a dose-dependent cytotoxic profile, which may be harmful to murine macrophages (J774 A.1) and may represent a health risk.

Low recombination rates and improving charge transfer as decisive conditions for high current densities and fill factors in ZnS complex systems.

The growth of ZnS photoelectrodes on ZnO particles identified as ZnO/ZnS(ZC + TAA) by the microwave-assisted hydrothermal method showed excellent photovoltaic parameters of JSC = 1.2 mA cm-2 and FF = 0.66, even compared to ZnS(ZC + TAA) used as a reference sample with JSC = 0.15 mA cm-2 and FF = 0.52. A careful analysis indicates that the better charge transfer and the higher resistance to recombination present in the ZnO/ZnS(ZC + TAA) samples were the origin of the best photovoltaic behavior. These assertions are supported by a set of samples synthesized from different precursors resulting in different crystal structures, which can be directly associated with current densities and fill factors. All aspects about synthesis and optical/electronic parameters associated with structural features will be available in this article.

Disclosing the Biocide Activity of α-Ag2-2xCuxWO4 (0 ≤ x ≤ 0.16) Solid Solutions.

In this work, α-Ag2-2xCuxWO4 (0 ≤ x ≤ 0.16) solid solutions with enhanced antibacterial (against methicillin-resistant Staphylococcus aureus) and antifungal (against Candida albicans) activities are reported. A plethora of techniques (X-ray diffraction with Rietveld refinements, inductively coupled plasma atomic emission spectrometry, micro-Raman spectroscopy, attenuated total reflectance-Fourier transform infrared spectroscopy, field emission scanning electron microscopy, ultraviolet-visible spectroscopy, photoluminescence emissions, and X-ray photoelectron spectroscopy) were employed to characterize the as-synthetized samples and determine the local coordination geometry of Cu2+ cations at the orthorhombic lattice. To find a correlation between morphology and biocide activity, the experimental results were sustained by first-principles calculations at the density functional theory level to decipher the cluster coordinations and electronic properties of the exposed surfaces. Based on the analysis of the under-coordinated Ag and Cu clusters at the (010) and (101) exposed surfaces, we propose a mechanism to explain the biocide activity of these solid solutions.

Analysis of cytotoxicity and genotoxicity in a short-term dependent manner induced by a new titanium dioxide nanoparticle in murine fibroblast cells.

The extensive use of titanium dioxide nanoparticles (TiO2 NPs) in cosmetics, food, personal care products, and industries brought concerns about their possible harmful effects. Nowadays it has become important to assess TiO2 NPs toxic effects as a way to understand their primary risks. In the cellular environment, after cell uptake, TiO2 NPs were described to induce reactive oxygen species (ROS) production, unbalance oxidative state, and activate apoptosis in several cell lines. Therefore, we aimed to evaluate the cytotoxicity and genotoxicity of a new TiO2 NP surface-functionalized with sodium carboxylic ligands in a murine fibroblast cell line (LA-9). TEM and DLS analyses were performed to define nanoparticle physicochemical characteristics. We evaluated the metabolic activity and LDH released after 24 h exposition to determine cytotoxic effects. Also, we evaluated DNA damage, intracellular reactive oxygen species (ROS) production, and apoptosis induction after 24 h exposure. The TiO2 NP impaired the cell membrane integrity at 1000 µg/mL, induced intracellular ROS production and late apoptosis at 24 h. The genotoxic effects were observed at all conditions tested at 24 h. Indeed, in fibroblasts exposed at 100 µg/mL was observed early apoptosis cells. The intracellular ROS content was increased in a dose-dependent manner. Thus, short-term exposure to TiO2 NP promoted cytotoxicity, genotoxicity and activated apoptosis pathways based on the potential role of oxygen species in the fibroblasts cell line.

Apoptosis and Oxidative Stress Triggered by Carbon Black Nanoparticle in the LA-9 Fibroblast.

BACKGROUND/AIMS: A new type of nanoparticle, called NP CB-EDA (Black Carbon modified with ethylenediamine), is commonly used in the oil industry. In the literature, few studies are found in biological models, making NP-EDA potential cytotoxicity in organisms unclear. As its large surface area is capable of interacting with the biological system, that interaction could lead to factors harmful to health. The objective of this study was to investigate the cytotoxic effect of NP CB-EDA on fibroblasts LA-9 at 24 and 48 hours, at different concentrations of the nanoparticle (1, 50, 250, 500 and 1000 µg/ml). METHODS: NP CB-EDA was characterized by TEM microscopy and its effect on cell viability (MTT method), cell morphology (optical microscopy), cell membrane (lactate dehydrogenase release - LDH), oxidative stress pathways (species levels reactive oxygen, ROS and nitrogen, NOS) and apoptosis/necrosis (flow cytometry) were evaluated. RESULTS: The results show that NP CB-EDA at concentrations of 500 and 1000 µg/ml form clusters. The nanoparticle can be absorbed by cells decreasing cell viability. There was damage to the cell membrane of fibroblasts LA 9, an increase in the production of ROS, NOS and pro-inflammatory interleukins TNF-α and IL-6; it was also observed an increase in % of cells in the state of apoptosis in the two periods analyzed, being this response more significant in 24 hours, and concentrations of 250, 500 and 1000 µg/ml presenting higher cytotoxicity. CONCLUSION: The data suggest that NP CB-EDA in fibroblasts LA9 presents cytotoxic potential, which is associated with oxidative stress and apoptosis.

Selective Synthesis of α-, ß-, and γ-Ag2WO4 Polymorphs: Promising Platforms for Photocatalytic and Antibacterial Materials.

Silver tungstate (Ag2WO4) shows structural polymorphism with different crystalline phases, namely, orthorhombic, hexagonal, and cubic structures that are commonly known as α, ß, and γ, respectively. In this work, these Ag2WO4 polymorphs were selectively and successfully synthesized through a simple precipitation route at ambient temperature. The polymorph-controlled synthesis was conducted by means of the volumetric ratios of the silver nitrate/tungstate sodium dehydrate precursors in solution. The structural and electronic properties of the as-synthesized Ag2WO4 polymorphs were investigated by using a combination of X-ray diffraction and Rietveld refinements, X-ray absorption spectroscopy, X-ray absorption near-edge structure spectroscopy, field-emission scanning electron microscopy images, and photoluminescence. To complement and rationalize the experimental results, first-principles calculations, at the density functional theory level, were carried out, leading to an unprecedented glimpse into the atomic-level properties of the morphology and the exposed surfaces of Ag2WO4 polymorphs. Following the analysis of the local coordination of Ag and W cations (clusters) at each exposed surface of the three polymorphs, the structure-property relationship between the morphology and the photocatalytic and antibacterial activities against amiloride degradation under ultraviolet light irradiation and methicillin-resistant Staphylococcus aureus, respectively, was investigated. A possible mechanism of the photocatalytic and antibacterial activity as well the formation process and growth of the polymorphs is also explored and proposed.

Structure, Photoluminescence Emissions, and Photocatalytic Activity of Ag2SeO3: A Joint Experimental and Theoretical Investigation.

In this paper, we report the synthesis of silver selenite (Ag2SeO3) by different methods [sonochemistry, ultrasonic probe, coprecipitation, and microwave-assisted hydrothermal methods]. These microcrystals presented a structural long-range order as confirmed by X-ray diffraction (XRD) and Rietveld refinements and a structural short-range order as confirmed by Fourier transform infrared (FTIR) and Raman spectroscopies. X-ray photoelectron spectroscopy (XPS) provided information about the surface of the samples indicating that they were pure. The microcrystals presented different morphologies and sizes due to the synthesis method as observed by field emission scanning electron microscopy (FE-SEM). The optical properties of these microcrystals were evaluated by ultraviolet-visible (UV-vis) spectroscopy and photoluminescence (PL) measurements. Thermal analysis confirmed the temperature stability of the as-synthetized samples. Further trapping experiments prove that the holes and hydroxyl radicals, to a minor extent, are responsible for the photocatalytic reactions. The experimental results are sustained by first-principles calculations, at the density functional theory (DFT) level, to decipher the structural parameters, electronic properties of the bulk, and surfaces of Ag2SeO3. By matching the experimental FE-SEM images and theoretical morphologies, we are capable of finding a correlation between the morphology and photocatalytic activity, along with photodegradation of the Rhodamine B dye under UV light, based on the different numbers of unsaturated superficial Ag and Se cations (local coordination, i.e., clusters) of each surface.

Uniaxial and Coaxial Electrospinning for Tailoring Jussara Pulp Nanofibers.

Jussara pulp (Euterpe edulis Mart.) is rich in bioactive compounds known to be protective mediators against several diseases. In this context, nevertheless, anthocyanins, the most abundant natural pigment in jussara, are sensitive to temperature, pH, oxygen, and light conditions, leading to instability during food storage or digestion, and, thus jeopardizing the antioxidant proprieties retained by these flavonoids and limiting industrial application of the pulp. The production of nanostructures, from synthetic and natural polymers, containing natural matrices rich in bioactive compounds, has been widely studied, providing satisfactory results in the conservation and maintenance of the stability of these compounds. The current work aimed to compare uniaxial and coaxial electrospinning operation modes to produce core-shell jussara pulp nanofibers (NFs). Additionally, the parameters employed in the electrospinning processes were optimize using response surface methodology in an attempt to solve stability issues for the bioactive compounds. The best experimental conditions provided NFs with diameters ranging between 110.0 ± 47 and 121.1 ± 54 nm. Moreover, the coaxial setup improved jussara pulp NF formation, while further allowing greater integrity of NFs structures.

New Multi-Walled carbon nanotube of industrial interest induce cell death in murine fibroblast cells.

The search for new nanomaterials has brought to the multifactorial industry several opportunities for use and applications for existing materials. Carbon nanotubes (CNT), for example, present excellent properties which allow us to assume a series of applications, however there is concern in the industrial scope about possible adverse health effects related to constant exposure for inhalation or direct skin contact. Thus, using cell models is the fastest and safest way to assess the effects of a new material. The aim of this study was to investigate the cytotoxic profile in LA9 murine fibroblast lineage, of a new multi-walled carbon nanotube (MWCNT) that was functionalized with tetraethylenepentamine (TEPA) to obtain better physical-chemical characteristics for industrial use. The modifications presented in the CNT cause concern, as they can change its initial characteristics, making this nanomaterial harmful. HR-TEM, FE-SEM and zeta potential were used for the characterization. Cytotoxicity and cell proliferation tests, oxidative and nitrosative stress analyzes and inflammatory cytokine assay (TNF-α) were performed. The main findings demonstrated a reduction in cell viability, increased release of intracellular ROS, accompanied by an increase in TNF-α, indicating an important inflammatory profile. Confirmation of the data was performed by flow cytometry and ImageXpress with apoptosis/necrosis markers. These data provide initial evidence that OCNT-TEPA has a cytotoxic profile dependent on the concentration of LA9 fibroblasts, since there was an increase in free radicals, inflammation induction and cell death, suggesting that continuous exposure to this nanoparticle can cause damage to different tissues in the organism.

Integration of experiment and computational modeling on the Tb doping process in CaMoO4 obtained by USP method: An efficient way to obtain photoluminescent materials.

In this paper, we present a combined experimental and theoretical study to disclose, the structure, electronic and optical properties of CaMoO 4 :xTb 3+ ( x = 1%, 2%, and 4%) microspheres. The microspheres were prepared by ultrasonic spray pyrolysis method and characterized by experimental and theoretical techniques. Theoretical calculations and XRD patterns indicate that these crystals have a scheelite-type tetragonal structure. The morphology of the CaMoO 4 :xTb 3+ ( x = 1%, 2% and 4% mol) samples were investigated from the FEG-SEM results and the formation of microspheres with a spherical shape were observed. The optical properties were investigated by UV-Vis and PL spectroscopy, as well as the chromaticity coordinates of these compounds. This also allowed us to understand the charge transfer process that happens in the singlet state and the excited states, generating the photoluminescence emissions of the Tb doping process in CaMoO 4 microspheres.

Microwave-Driven Hexagonal-to-Monoclinic Transition in BiPO4: An In-Depth Experimental Investigation and First-Principles Study.

Present theoretical and experimental work provides an in-depth understanding of the morphological, structural, electronic, and optical properties of hexagonal and monoclinic polymorphs of bismuth phosphate (BiPO4). Herein, we demonstrate how microwave irradiation induces the transformation of a hexagonal phase to a monoclinic phase in a short period of time and, thus, the photocatalytic performance of BiPO4. To complement and rationalize the experimental results, first-principles calculations have been performed within the framework of density functional theory. This was aimed at obtaining the geometric, energetic, and structural parameters as well as vibrational frequencies; further, the electronic properties (band structure diagram and density of states) of the bulk and corresponding surfaces of both the hexagonal and monoclinic phases of BiPO4 were also acquired. A detailed characterization of the low vibrational modes of both the hexagonal and monoclinic polymorphs is key to explaining the irreversible phase transformation from hexagonal to monoclinic. On the basis of the calculated values of the surface energies, a map of the available morphologies of both phases was obtained by using Wulff construction and compared to the observed scanning electron microscopy images. The BiPO4 crystals obtained after 16-32 min of microwave irradiation provided excellent photodegradation of Rhodamine B under visible-light irradiation. This enhancement was found to be related to the surface energy and the types of clusters formed on the exposed surfaces of the morphology. These findings provide details of the hexagonal-to-monoclinic phase transition in BiPO4 during microwave irradiation; further, the results will assist in the design of electronic devices with higher efficiency and reliability.

Probing the Site-Selective Doping in SrSnO3:Eu Oxides and Its Impact on the Crystal and Electronic Structures Using Synchrotron Radiation and DFT Simulations.

The impact of Eu3+ doping at the Sr2+ and Sn4+ sites in SrSnO3 on its structural and electronic properties was studied and correlated with the photocatalytic efficiency. The compounds were synthesized using a modified Pechini method. Refinement of the synchrotron X-ray diffraction (S-XRD) data showed that the samples had an orthorhombic Pbnm symmetry. The incorporation of Eu into the lattice led to increased short- and long-range disorder, inducing additional distortion in the SnO6. XANES measurements revealed that mixed Eu valences (Eu3+ and Eu2+) were present in Eu-doped samples, and DFT calculations confirmed the presence of these ions at Sr2+/Sr4+ sites in the SrSnO3, resulting in changes in the electronic behavior. The catalytic performance toward Remazol yellow dye photodegradation and the catalysts' surface properties were also evaluated. The catalytic efficiency followed the order of Sr(Sn0.99Eu0.01)SnO3 > (Sr0.99Eu0.01)SnO3 > SrSnO3. The order was clearly related to selected-site doping that changed the degree of the inter- and intraoctahedral distortion and the introduction of different Eu midgap states, which apparently favor charge separation upon photoexcitation during photocatalysis. The results shown here are of great importance to the functionalization of SrSnO3 and other perovskite materials by lanthanoid ions, especially Eu3+, for effective applications as photocatalysts.

α-AgVO3 Decorated by Hydroxyapatite (Ca10(PO4)6(OH)2): Tuning Its Photoluminescence Emissions and Bactericidal Activity.

Defect-related luminescent materials have attracted interest because of their excellent optical properties and are considered as a less expensive and nontoxic alternative to commonly used lanthanide-based optical systems. These materials are fundamentally and technologically important for the next generation of full-color tunable light-emitting diodes as well as in the biomedical field. In this study, we report the preparation of α-silver vanadate (α-AgVO3, AV) decorated by hydroxyapatite (Ca10(PO4)6(OH)2, HA) with intense photoluminescence (PL) emissions at various HA/AV molar ratios (1:1-1:1/32) by a simple route based on chemical precipitation. The well-defined diffraction peaks observed by X-ray diffraction were all indexed to the monoclinic AV and hexagonal HA phases. Analysis of the results obtained by Fourier transform infrared spectroscopy reveals the presence of short-range structural order as deduced by the characteristic vibrational modes assigned to AV and HA systems. Characterization by scanning and transmission electron microscopies confirms the presence of AV and HA micro- and nanorods, respectively. UV-vis spectroscopy renders band gap energies of 5.80 eV for HA and in the range 2.59-2.65 eV for pure AV and HA/AV samples. The PL data reveal the presence of broad-band emission profiles, typical of defect-related optical centers in materials. Depending on the molar ratio, the emission can be completely tunable from the blue to red spectral regions; in addition, pure white color emission was obtained. On the basis of these results, we propose an order-disorder model induced by structural and interface defects to explain the PL emissions in the HA/AV system. Moreover, our results show that HA/AV composites have superior bactericidal activity against Staphylococcus aureus (methicillin-resistant and methicillin-susceptible) and can be used as a novel multifunctional material.

Unveiling the efficiency of microwave-assisted hydrothermal treatment for the preparation of SrTiO3 mesocrystals.

Material processing has become essential for the proper control, tuning and consequent application of the properties of micro/nanoparticles. In this case, we report herein the capability of the microwave-assisted hydrothermal (MAH) method to prepare the SrTiO3 compound, as a case study of inorganic compounds. Analyses conducted by X-ray diffraction, X-ray photoelectron and X-ray absorption spectroscopies confirmed that the MAH route enables the formation of pristine SrTiO3. The results indicated that the combination of thermal and non-thermal effects during the MAH treatment provides ideal conditions for an efficient and rapid synthesis of pristine SrTiO3 mesocrystals. Scanning electron microscopy images revealed a cube-like morphology (of ca. 1 µm) formed via a self-assembly process, influenced by the MAH time. Additionally, photoluminescence measurements revealed a broad blue emission related to intrinsic defects, which decreased with the MAH synthesis time.

Computational Chemistry Meets Experiments for Explaining the Geometry, Electronic Structure, and Optical Properties of Ca10V6O25.

In this paper, we present a combined experimental and theoretical study to disclose, for the first time, the structural, electronic, and optical properties of Ca10V6O25 crystals. The microwave-assisted hydrothermal (MAH) method has been employed to synthesize these crystals with different morphologies, within a short reaction time at 120 °C. First-principle quantum mechanical calculations have been performed at the density functional theory level to obtain the geometry and electronic properties of Ca10V6O25 crystal in the fundamental and excited electronic states (singlet and triplet). These results, combined with the measurements of X-ray diffraction (XRD) and Rietveld refinements, confirm that the building blocks lattice of the Ca10V6O25 crystals consist of three types of distorted 6-fold coordination [CaO6] clusters: octahedral, prism and pentagonal pyramidal, and distorted tetrahedral [VO4] clusters. Theoretical and experimental results on the structure and vibrational frequencies are in agreement. Thus, it was possible to assign the Raman modes for the Ca10V6O25 superstructure, which will allow us to show the structure of the unit cell of the material, as well as the coordination of the Ca and V atoms. This also allowed us to understand the charge transfer process that happens in the singlet state (s) and the excited states, singlet (s*) and triplet (t*), generating the photoluminescence emissions of the Ca10V6O25 crystals.

Laser-induced formation of bismuth nanoparticles.

In the current communication, the synthesis of metallic Bi nanoparticles with coexisting crystallographic structures (rhombohedral, monoclinic, and cubic) obtained via direct femtosecond laser irradiation of NaBiO3 is demonstrated for the first time. By exploring the use of high laser power values, it is revealed that the promoted laser-mediated reactions lead to the synthesis of coexisting phases in metal nanoparticles, which may be a widely occurring phenomenon in other materials under femtosecond laser irradiation, and a fundamental concern for laser-based nanofabrication.