Concomitant Light-Reversible Magnetic Response in Multiferroic Oxide Heterostructures for Multiphysics Applications.

The concept of multiphysics, where materials respond to diverse external stimuli, such as magnetic fields, electric fields, light irradiation, stress, heat, and chemical reactions, plays a fundamental role in the development of innovative devices. Nanomanufacturing, especially in low-dimensional systems, enhances the synergistic interactions taking place on the nanoscale. Light-matter interaction, rather than electric fields, holds great promise for achieving low-power, wireless control over magnetism, solving two major technological problems: the feasibility of electrical contacts at smaller scales and the undesired heating of the devices.

Reversible optical control of magnetism in engineered artificial multiferroics.

Optical means instead of electric fields may offer a new pathway for low-power and wireless control of magnetism, holding great potential to design next-generation memory and spintronic devices. Artificial multiferroic materials have shown remarkable suitability as platforms towards the optical control of magnetic properties. However, the practical use of magnetic modulation should be both stable and reversible and, particularly, it should occur at room temperature.

CNTs/Fe-BTC Composite Materials for the CO-Photocatalytic Reduction to Clean Fuels: Batch and Continuous System.

CNTs/Fe-BTC composite materials were synthesized with the one-step solvothermal method. MWCNTs and SWCNTs were incorporated in situ during synthesis. The composite materials were characterized by different analytical techniques and used in the CO-photocatalytic reduction to value-added products and clean fuels.

Cost-effective screen printing approach for Ce/Nd-doped ZnAlO films: tuning crystallinity induced by the substrate.

Near-infrared (NIR) emitting phosphors are currently receiving considerable attention owing to their high demand in various applications, such as light detection and ranging (LiDAR), short-range communications, security, biosensing and night vision lighting applications. The miniaturization of photonic components demands the integration of thin films into exploitable devices. In this context, NIR emitting ZnAlO:Ce/Nd films of hundreds of nanometer thickness are synthesized using a scalable and cost-efficient approach to screen printing.

Photocatalytic Degradation of Dyes Using Titania Nanoparticles Supported in Metal-Organic Materials Based on Iron.

Composite materials based on titania nanoparticles (TiO NPs) and three metal-organic frameworks (MOFs) called ((Fe (III) (OH) (1,4-BDC)), MILs (Materials Institute Lavoisier)), (FeO(HO)OH(BTC)), and (iron-benzenetricarboxylate) with different percentages of TiO NPs (0.5, 1, and 2.5% wt.

Deep-Ultraviolet Emitter: Rare-Earth-Free ZnAlO Nanofibers via a Simple Wet Chemical Route.

Deep-UV (180-280 nm) phosphors have attracted tremendous interest in tri-band-based white light-emitting diode (LED) technology, bio- and photochemistry, as well as various medical fields. However, the application of many UV-emitting materials has been hindered due to their poor thermal or chemical stability, complex synthesis, and environmental harmfulness. A particular concern is posed by the utilization of rare earths affected by rising price and depletion of natural resources.

Aluminate-Based Nanostructured Luminescent Materials: Design of Processing and Functional Properties.

Interest in luminescent materials has been continuously growing for several decades, looking for the development of new systems with optimized optical properties. Nowadays, research has been focused on the development of materials that satisfy specific market requirements in optoelectronics, radioelectronics, aerospace, bio-sensing, pigment applications, etc. Despite the fact that several efforts have made in the synthesis of organic luminescent materials, their poor stability under light exposure limits their use.

Effect of the NaO-NbO-PO glass additive on the structure, dielectric and energy storage performances of sodium niobate ceramics.

A phosphate glass NaO-NbO-PO (NPP) is incorporated into NaNbO (NN) ceramics to examine its impact on the density, rearrangement of structural units, dielectric and energy storage features of the elaborated composites. The sodium niobate ceramic (NN) is prepared using the solid state process, whereas, the NaO-NbO-PO (NPP) glasses are produced using the method of conventional melt quenching. The glass (NPP) is added to the ceramic (NN) according to the composition (100-x) NN-xNNP; (x = 0, 2.

Photocontrolled Strain in Polycrystalline Ferroelectrics via Domain Engineering Strategy.

The use of photonic concepts to achieve nanoactuation based on light triggering requires complex architectures to obtain the desired effect. In this context, the recent discovery of reversible optical control of the domain configuration in ferroelectrics offers a light-ferroic interplay that can be easily controlled. To date, however, the optical control of ferroelectric domains has been explored in single crystals, although polycrystals are technologically more desirable because they can be manufactured in a scalable and reproducible fashion.

Towards Blue Long-Lasting Luminescence of Eu/Nd-Doped Calcium-Aluminate Nanostructured Platelets via the Molten Salt Route.

Calcia-alumina binary compounds doped with rare earths and some transition metals cations show persistent luminescence from the visible to the infrared range. Specifically, the blue light can be obtained through the Eu activator center in a potential host, such as dodecacalcium hepta-aluminate (CaAlO) and monocalcium aluminate (CaAlO). By doping with Nd, the persistent luminescence can be substantially prolonged; for this reason, the Eu/Nd pair is a potential choice for developing long-lasting blue luminescence.

Photo-Controlled Ferroelectric-Based Nanoactuators.

Finding a feasible principle for a future generation of nano-optomechanical systems is a matter of intensive research, because it may provide new device prospects for optoelectronics and nanomanipulation techniques. Here we show that the strain of a ferroelectric crystal can be manipulated to achieve macroscopic, stable, and reproducible dimensional changes using illumination with photon energy below the material bandgap. The photoresponse can be activated without direct light incidence on the actuation area, because the cooperative nature of the phenomenon extends the photoinduced strain to the whole material.

The fight against multidrug-resistant organisms: The role of ZnO crystalline defects.

This article reports the excellent antimicrobial response of nanoparticulate ZnO against multidrug-resistant organisms (MDROs). We demonstrate that the enhanced antimicrobial activity against MDROs depends on the crystalline defects of ZnO. Hence, this work provides insights on the ZnO-microorganism interactions, and we pose combined physico-chemical action mechanisms against resistant bacteria.

Unveiling the role of the hexagonal polymorph on SrAlO-based phosphors.

In persistent luminescence materials, the SrO-AlO system has been mainly studied due to its chemical stability, higher photoluminescence response and longest green-afterglow times. Specifically, the research has focused on SrAlO doped with europium and dysprosium. SrAlO has two polymorphs: monoclinic polymorph (space group 2) and hexagonal polymorph (space group 622).

Light-Induced Capacitance Tunability in Ferroelectric Crystals.

The remote controlling of ferroic properties with light is nowadays a hot and highly appealing topic in materials science. Here, we shed light on some of the unresolved issues surrounding light-matter coupling in ferroelectrics. Our findings show that the capacitance and, consequently, its related intrinsic material property, i.

Experimental evidence of charged domain walls in lead-free ferroelectric ceramics: light-driven nanodomain switching.

The control of ferroelectric domain walls at the nanometric level leads to novel interfacial properties and functionalities. In particular, the comprehension of charged domain walls, CDWs, lies at the frontier of future nanoelectronic research. Whereas many of the effects have been demonstrated for ideal archetypes, such as single crystals, and/or thin films, a similar control of CDWs on polycrystalline ferroelectrics has not been achieved.

Template-Assisted Wet-Combustion Synthesis of Fibrous Nickel-Based Catalyst for Carbon Dioxide Methanation and Methane Steam Reforming.

Efficient capture and recycling of CO enable not only prevention of global warming but also the supply of useful low-carbon fuels. The catalytic conversion of CO into an organic compound is a promising recycling approach which opens new concepts and opportunities for catalytic and industrial development. Here we report about template-assisted wet-combustion synthesis of a one-dimensional nickel-based catalyst for carbon dioxide methanation and methane steam reforming.

Exploring New Mechanisms for Effective Antimicrobial Materials: Electric Contact-Killing Based on Multiple Schottky Barriers.

The increasing threat of multidrug-resistance organisms is a cause for worldwide concern. Progressively microorganisms become resistant to commonly used antibiotics, which are a healthcare challenge. Thus, the discovery of new antimicrobial agents or new mechanisms different from those used is necessary.

Precise Tuning of the Nanostructured Surface leading to the Luminescence Enhancement in SrAlO Based Core/Shell Structure.

Intensive research has been focused on the synthesis of long-lasting SrAlO:EuDy in luminescent materials field. Traditionally, SrAlO:EuDy is synthesized in bulk form by solid state. However, their development remains restrained due to this technique is not compatible with large-scale production, sustainability and nanometer-scale requirements.

Self-Forming 3D Core-Shell Ceramic Nanostructures for Halogen-Free Flame Retardant Materials.

The synthesis of aluminum phosphates-based composites has been widely studied during the past decade because of the promising industrial application of these materials. Here we show a simple one-pot heterogeneous precipitation approach to fabricate a sepiolite-phosphate (SepP) composite with adequate control of the size and dispersion of the phosphate nanoparticles. This coupling between aluminum phosphate and sepiolite nanofibers results in the development of a novel three-dimensional rigid supported phosphate structure, which is generated during the thermal treatment.

Original Synthetic Route To Obtain a SrAl2O4 Phosphor by the Molten Salt Method: Insights into the Reaction Mechanism and Enhancement of the Persistent Luminescence.

SrAl2O4:Eu(2+), Dy(3+) has been extensively studied for industrial applications in the luminescent materials field, because of its excellent persistent luminescence properties and chemical stability. Traditionally, this strontium aluminate material is synthesized in bulk form and/or fine powder by the classic solid-state method. Here, we report an original synthetic route, a molten salt assisted process, to obtain highly crystalline SrAl2O4 powder with nanometer-scale crystals.

Lead-Free Piezoceramics: Revealing the Role of the Rhombohedral-Tetragonal Phase Coexistence in Enhancement of the Piezoelectric Properties.

Until now, lead zirconate titanate (PZT) based ceramics are the most widely used in piezoelectric devices. However, the use of lead is being avoided due to its toxicity and environmental risks. Indeed, the attention in piezoelectric devices has been moved to lead-free ceramics, especially on (K,Na)NbO3-based materials, due to growing environmental concerns.

Ferroelectric domain wall motion induced by polarized light.

Ferroelectric materials exhibit spontaneous and stable polarization, which can usually be reoriented by an applied external electric field. The electrically switchable nature of this polarization is at the core of various ferroelectric devices. The motion of the associated domain walls provides the basis for ferroelectric memory, in which the storage of data bits is achieved by driving domain walls that separate regions with different polarization directions.

Insights into the dielectric and luminescent properties of Na(0.5)Pr(0.003)Bi(0.497-x)La(x)TiO3 synthesized by the Pechini method.

Lead-free ferroelectric ceramics based on the Na(0.5)Bi(0.5)TiO3 system, in solid solution with Pr(3+) and La(3+), are synthesized by the Pechini method at low temperature.

Correlation between the structure and the piezoelectric properties of lead-free (K,Na,Li)(Nb,Ta,Sb)O3 ceramics studied by XRD and Raman spectroscopy.

This article reviews on the use of Raman spectroscopy for the study of (K,Na,Li)(Nb,Ta,Sb)O(3) lead-free piezoceramics. Currently, this material appears to be one of the most interesting and promising alternatives to the well-known PZT piezoelectric materials. In this work, we prepare piezoceramics with different stoichiometries and study their structural, ferroelectric, and piezoelectric properties.

Piezoceramics properties as a function of the structure in the system (K,Na,Li)(Nb,Ta,Sb)O3.

The influence of the sintering conditions and stoichiometry on the crystalline symmetry and electrical properties of the system (K(0.44+x)Na(0.52)Li(0.