Mesoporous materials have typical average pore diameters in the range 20 – 500 Å, which are usually accompanied by high specific surface area (ABET) and large pore volume (Vp) with narrow pore size distributions. These features are very attractive for potential application as catalysts and adsorbents. Mesoporous materials are usually prepared by soft templating or nanocasting process. The latter approach is based on the replication of hard-templates, such as mesoporous silica (e.g. SBA-15), being a very flexible and suitable method to obtain stable and predictable pore mesostructures. However, the chemical compatibility between the template and the precursors must be ensured.

There is a wide range of surface analysis techniques which are, generally, complementary and provide target information for depths near the surface. Nuclear techniques, which are non-destructive, provide for analysis over a few microns close to the surface giving absolute values of concentrations of isotopes and elements. They have been applied in areas such as scientific, technologic, industry, arts and medicine, using MeV ion beams. Nuclear reactions permit tracing of isotopes with high sensitivities. We use ion-ion reactions and the energy analysis method. At a suitable energy of the incident ion beam, an energy spectrum is recorded of ions from the reaction, coming from several depths in the target. Such spectra are computationally predicted, giving target composition and concentration profile information. Elastic scattering is a particular and important case. A computer program has been developed in this context, mainly for flat targets. The non-flat target situation arises as an extension.

The properties of nanostructured advanced materials such as carbon nanotubes and nanocrystalline diamond (CNT/NCD) hybrids are known to be closely linked to their morphology, therefore requiring reliable measuring techniques based on quantitative microscopy supported by digital image processing. The development of such techniques is strongly related to hardware evolution and software availability for digital image processing and analysis.

Zinc oxide (ZnO) has been one of the most studied materials in the last decades. Either as bulk material, epilayers or nanostructures, this direct wide band gap semiconductor is known to possess great potential for fundamental science and modern technology applications.

Multiferroic materials, combining at least two of three properties: ferromagnetism, ferroelectricity and ferroelasticity in the same phase, have been widely studied nowadays and have tremendous potential for multifunctional applications, although magnetoelectric multiferroics are difficult to obtain. Recently, dielectric and magnetic anomalies were found to be coupled in the incipient ferroelectrics SrTiO3 and KTaO3 doped with Mn on A-site of ABO3 perovskite lattice.

ZnO is a promising material for use in solar cell applications which require antireflective coatings and transparent conducting materials in front contacts. Its resistivity can be reduced by appropriate doping with different group III elements, which act as donors, without sacrificing optical transmission. Besides, it constitutes a non-toxic and cheap alternative to ITO (In2O3:SnO2), which is nowadays commonly used as transparent conducting oxide (TCO) in optoelectronic devices. Al(III) is one of the cheapest elements on nature, and has been therefore one of the first candidates to be used as a dopant. However recent studies demonstrate that for similar amounts of dopant the use of Ga largely improves both the optical and electrical properties of the films. The interface between Si (used as substrate) and the corresponding TCO is a critical part of Si-based solar cells, since the conversion efficiency may be profoundly altered by the presence of recombination centers formed at the interface. In this work we present a comparison of Si/ZnO, Si/ZnO:Ga and Si/ZnO:Al interfaces (with [dopant]/[Zn] = 2%) by using HRTEM and associated spectroscopies. Resistivity values of the films are: ρ(ZnO) = 4.4 × 10-2 Ω × cm; ρ(Ga:ZnO) = 6.3 × 10-4 Ω × cm; ρ(Al:ZnO) = 2.9 × 10-3 Ω × cm. and the films optical transmitance is larger than 80% along the visible spectrum.

Thermoelectric ceramic materials for practical applications must present high thermopower and relatively low electrical resistivity along with high chemical stability at high temperatures. These properties can be found in thermoelectric ceramics, for example in misfit cobaltites. These materials possess a high crystallographic anisotropy which is reflected on their thermoelectric properties. Therefore, controlling their grains orientation is mandatory in order to achieve better performance for practical applications. In this perspective, texturing methods can play an important role for enhancing the final properties of the bulk materials.

SbVO4 series of compounds could be used as oxidation catalysts of industrial interest yielding 20% cheaper acrylonitrile by the ammoxidation of propane compared to current method producing 8×106 ton/year based on propylene as starting reactant.

In the present work, we present the microstructural study of a cast magnesium alloy AM60B processed by Friction Stir Processing (FSP) in order to achieve Ultra-Fine Grain (UFG) size (200–700nm) in the stirred zone. Focused ion beam (FIB) has been used for sample preparation, and transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and selected area electron diffraction (SAED) for the structural characterization. To explain the differences induced by the FSP, two lamellas obtained by FIB from the bottom and the upper part of the cross-section of the nugget are compared to one extracted from the parent material (unaffected zone A). The obtained results show the remarkable homogenization and grain refinement produced in the structure in the processed zone, as previous reported works indicate. The microstructure of the as cast base material reveals the presence of dendrites of solid solution of Al in Mg (α-phase), with an average grain size of ~400–500 µm, and a partially divorced eutectic structure at the interdendritic spaces, where the massive and lamellar β-Mg17Al12 intermetallic phase can be observed (Figure 1). The SAED on one particle of β-phase shows a diffraction pattern that fits the crystalline structure of the cubic I -4 3 m space group (Nº 217). Also Mn containing phases were homogeneously distributed throughout the section. The performed analyses demonstrate that these particles are basically Al-Mn binary phases containing trace elements as Si or Fe, and the measured Mn/Al ratio allow to classify them into two types previously reported: Type I are particles of equiaxed or almost rounded shape and type II are needle like or flowerlike particles, with a lower Mn/Al ratio.

The production of a Tantalum solid electrolytic capacitor requires the impregnation of MnO2 by pyrolysis in one of the several manufacturing steps. It has been reported that niobium oxides are a good alternative, presenting potentially better dielectric properties and a better cost effectiveness. Thus, it is important to study the conditions and the effect of the MnO2 impregnation on niobium oxide in order to understand and optimize the parameters of this process. The morphology and microstructure of the anode is one of the most important aspects that interfere with the dielectric properties of the capacitor. In this work, it is presented a study of the morphology and microstructure of different niobium oxide anodes after electrochemical oxidation (NbO/Nb2O5 core-shell grain structure), and after MnO2 impregnation with different pyrolysis temperatures. This impregnation is made by dipping the anodes, with the NbO/Nb2O5 core-shell structure, in a slurry of Mn(NO3)2. Heating this slurry while the anode is dipped, will lead to a pyrolysis reaction where the liberation of NO2 occurs as a gas, and where the product MnO2 solidifies around the grains.

Perovskite manganites have been the focus of worldwide research during the last two decades because of the observation of colossal magnetoresistance (CMR) effect. These materials have potential applications in magnetic field sensors, spin filters, infrared bolometers and cathodes for solid oxide fuel cells. Such manganites are also important from the fundamental study viewpoint as they offer interplay among various degrees of freedom viz. spin, lattice and charge ordering. Moreover, phase separation may occur in manganites with low concentration of the dopant. In such scenario, ferromagnetic metallic clusters are embedded in antiferromagnetic insulating matrix. The fraction of these magnetic phases may vary from the nano- to micro-scale. With higher dopant concentration, the percolation of these magnetic metallic clusters leads to the apparent CMR effect. In this study we focus our attention to the low doped La0.8Sr0.2MnO3 (LSMO) manganite and investigate the possible magnetic phase separation and effect of variation in grain size on the magnetic domain size. La0.8Sr0.2MnO3 possesses Curie temperature (TC) higher than room temperature, therefore the material is supposed to be in the magnetic state at room temperature.

Recently, much attention has been given to directional solidified eutectic (DSE) materials for functional and structural applications. DSE materials take advantage from their microstructural features. Typically, DSE are dense homogeneous materials composed by fine microstructures without grain boundaries (GBs). Since impurities and defects typically concentrate at GBs, their deleterious effects on the mechanical, thermal and electrical properties can thus be minimized.

Cubic zinc gallate (c-ZnGa2O4) has attracted the attention of the scientific community due to its potential phosphor applications, namely in field emission displays (FEDs) and other electroluminescent devices. Among other advantages, this oxide matrix shows superior thermal and chemical stability when compared to ZnS based phosphors. Most of the above mentioned works comprise nanostructures, thin films or pressed pellets while scarce information is found on bulk c-ZnGa2O4 material. In particular, no records were found regarding c-ZnGa2O4 crystal growth by the laser floating zone (LFZ) technique. In this work, crystalline fibres of manganese doped (0.01 mol %) zinc gallate were produced via LFZ in order to investigate its applicability in efficient phosphors. The transition metal ions are suitable activators and show some advantages over the widely used rare earths, namely at environmental and economic levels.

Top-down approaches for continuous scaling-down of devices and components in semiconductor industries is getting increasingly difficult and expensive, and thus bottom–up strategies, e.g., growth of functional nano-structures using nanowires or nanotubes are being explored rather than patterning and etching. Carbon nanotubes (CNTs) are an interesting option under consideration due to their extraordinary physical and electrical properties that make them suitable for microelectronic applications, such as, semiconductor field-effect-transistors (FET) and capacitors. In recent years, the fabrication of one-dimension (1D) ferroelectric (FE) nanostructures have been investigated as a capacitor for future 3D memories, however several difficulties need to be overcome in particular fabrication and characterization. In this work, the fabrication of ferroelectrics (FE) (e.g., Pb1-xZrxTiO3 (PZT) and BaTiO3 (BT)) multi-walled carbon nanotubes (MWCNTs) composites were synthesised by chemical solution deposition (CSD) method, namely sol gel. Later, the composites were investigated using scanning electron microscope (SEM) equipped with energy dispersive spectroscopy facilities and transmission electron microscopy (TEM) in addition to X Ray Diffraction (XRD) and Fourier Transform Infrared (FTIR), to address the compatibility between FE and CNTs.

Composites of tungsten carbide (WC) and stainless steel (SS) have been produced through an innovative powder coating technique using sputtering. These composites showed remarkable mechanical properties after vacuum sintering, in spite of significant amounts of brittle eta-phase, (M,W)6C. The formation of eta-phase is almost inevitable, because it is thermodynamically favoured for stoichiometric C in the WC-SS system and accelerated in the SS coated WC particles, due to the reduced diffusion distances between WC and SS and the nanocrystalline character of the metallic coating. Surprisingly, the mechanical properties are not seriously affected by the eta-phase. In fact, relatively tough and harder materials have been obtained compared to similar compositions of WC-Co. In order to understand the microscopic reason for the reported mechanical strength, in-depth structural analysis of grain boundaries and interfaces was performed by electron microscopy.

Barium titanate (BT), a typical ferroelectric material with a tetragonal structure bellow TC ≈125 ºC has found widespread applications especially in electronic devices. However, modern electronics demand very small functional structures and, as a consequence nanostructures of ferroeletrics are being considered. However it was observed that there is a critical size for BT nanostructures below which TC decreases, the paraelectric cubic phase is stabilized at room temperature and then ferroelectricity may no longer exist. These observations have stimulated an exponential growth of research aiming to understand the effect of scaling on the ferroelectric properties. In addition some theoretical studies predicted the enhancement of ferroelectricity in anisotropic “cylindrical” shaped nanoparticles. Therefore, the morphology control and fabrication of ferroelectric nanostructures with different size and shapes are of key importance. Within this context, we demonstrated that the control of the morphology of BT nanoparticulates can be achieved by hydrothermal method.

Piezoelectric materials find important applications in micro- and nano-electromechanical systems (MEMS/NEMS). Pb(Zrx,Ti1-x)O3 (PZT) is currently the most widely used composition for such applications but due to environmental concerns over the toxicity of lead, lead free alternative materials are required. K0.5Na0.5NbO3 (KNN) is considered as a potential lead free piezoelectric but the current generation of monolithic ceramics has inferior electromechanical properties as compared to PZT. Consequently, there is great interest in improving the piezoelectric properties of KNN ceramics and various methods such as doping, hot-pressing and texturing are currently being studied. KNN single crystals like lead based single crystals have shown better electromechanical properties as compared to their ceramic counterparts. In addition, the behavior of a ferroelectric is largely dependent on its local domain response to an applied electrical or mechanical loading. Therefore, to understand better the material’s macroscopic properties, it is essential to access local ferroelectric domains behavior which collectively determines the electromechanical performance.

Multiferroics are currently of great interest for applications in microelectronics namely in future data storage and spintronic devices. These materials couple simultaneously ferroelectric and ferromagnetic properties and have potentially different applications resulting from the coupling between their dual order parameters. A true multiferroic material is single phase. However, the known true multiferroic materials possess insufficient coupling between the two phenomena or their magnetoelectric response occurs at temperatures too low to be useful in practical applications. But a tremendous progress in the field of microelectronics can be expected if one is able to design an effective multiferroic material with ideal coupling of the ferromagnetic and ferroelectric properties to suit a particular application. Within this context composite structures are gaining considerable interest and different strategies in terms of materials microstructure have been proposed including horizontal multilayers and vertical heterostructures. In the horizontal multilayer heterostructures, the alternating layers of conventional ferro/ferrimagnetic and ferroelectric phases are grown, while in the vertical heterostructures nanopillars of the ferro/ferrimagnetic phase are embedded in a ferroelectric matrix. The later structures show advantages over the first ones because promote larger interfacial surface area and are intrinsically heteroepitaxial in three dimensions; which is expected to allow a stronger coupling between ferroelectric and ferromagnetic components.

Hydroxyapatite, with a composition that resembles the mineral phase of bone, is often used as a coating of metallic prostheses to improve the adhesion and osseointegration of implants in different parts of the skeleton. Among the available techniques that allow the deposition of this material on metallic substrates, Pulsed Laser Deposition (PLD) is capable of producing high quality and highly biocompatible coatings with excellent final attachment.

The increasing demand of sources of energy such as oil and natural gas induces at the steel industry a development on low carbon microalloyed steels for pipeline applications in order to achieve excellent mechanical properties of strength and toughness at a reduced cost. To obtain an adequate fine-grained final structure, the strict control of thermomechanical processing and accelerated cooling is crucial. Depending on the thermomechanical processing conditions and chemical composition, pipeline steels can present different microstructures. Several authors have found that the microstructure of acicular ferrite usually provides an optimum combination of mechanical properties. Higher levels of austenite strengthening before cooling promote a refinement of final microstructure but can also restrict the fraction of low temperature transformation products such as acicular ferrite.