Simulation by a Genetic Algorithm and Location by the Non-linear Acoustic Technique of the Shear Damage to the Fiber-Matrix Interface of a Hybrid Composite Material Alfa-Carbon / Epoxy

The objective of this paper is to study the location of the shear damage to the fiber matrix interface of a hybrid composite material by using the nonlinear acoustic technique, which is commonly described by the addition of a non-linear term in Hooke’s law. The genetic simulation is based on the probabilistic Weibull model including non-linear parameter β. The results obtained show good agreement between the numerical simulation and the actual behavior of two hybrid composite materials: alfa-carbon/Epoxy and glass-carbon/ Epoxy. In addition the results are similar to those obtained by the analytical model, which based on the Cox and Weibull formalism. The extended study for nanocomposite materials is interesting in the future.

Impact of photocatalysis on carotenoic acid dye-sensitized solar cells

Sensitized mesoporous titania is of increasing interest for catalysis and photovoltaic devices such as dye-sensitized solar cells (DSCs). For photovoltaic applications, the catalytic properties of TiO2 can cause degradation of the dyes during device fabrication. This is especially the case if natural sensitizers are used. We addressed this issue by fabrication of carotenoic acid sensitized solar cells under inert and ambient assembly conditions. The DSCs were investigated by currentvoltage and quantum efficiency measurements. Further characterization of the cells was made using impedance spectroscopy. The conversion efficiency of the DSCs prepared under inert conditions improved by at least 25% and the devices showed an enhanced reproducibility. The improvement of the DSCs correlated with the conversion efficiency of the sensitizers under inert conditions. We conclude that the photocatalytic bleaching depends on the electron injection efficiency of the sensitizer. Hence carotenoic acids support their own degradation. However, the photocatalytic decomposition of the sensitizers can be avoided by fabrication of the DSCs under inert conditions.

Development of Smart Nanocontainers With A Zinc Phosphate Core and A pH-Responsive Shell for Controlled Release of Immidazole

A simple and flexible method has been developed to fabricate reversibly switchable nanocontainers (by layer by layer assembly) using zinc phosphate (ZP) nanoparticles as a core material and subsequent deposition of oppositely charged species of polyelectrolyte (polyaniline and polyacrylic acid) and organic corrosion inhibitor (immidazole). Immidazole was entrapped between polyaniline (PANI) and polyacrylic acid (PAA). The PAA nanovalve can control the access of immidazole molecules to and from the nanocontainers. The average particle size of the synthesized nanocontainer was found to be in the range of 250–500 nm. X-ray diffraction (XRD), particle size analysis (PSA), zeta potential, and fourier transform infrared spectroscopy (FTIR) analysis confirms the successful formation of the layered structure of nanocontainers. UV-vis spectroscopy was used to analyze the release rate of immidazole in media of different pH as a function of time. This core-shell nanostructure can have potential applications in corrosion inhibition paint formulation.

Electron beam curing of CoFe2O4 nanoparticles

Three different synthesis methods were given for the preparation of CoFe

Rutherford Backscattering Spectroscopy of Mass Transport by Transformation of PbI2 into CH3NH3PbI3 within np-TiO2

Mass transport during transformation of PbI

In situ syntheses of semiconducting nanoparticles in conjugated polymer matrices and their application in photovoltaics.

Hybrid solar cells based on conjugated polymers and inorganic semiconducting nanoparticles combine beneficial properties of organic and inorganic semiconductors and are, therefore, an exciting alternative to pure organic or inorganic solar cell technologies. Several approaches for the fabrication of hybrid solar cells are already elaborated and explored. In the last years routes have emerged, where the nanoparticles are prepared directly in the matrix of the conjugated polymer. Here, the conjugated polymer prevents the nanoparticles from excessive growth and thereby makes additional capping agents obsolete. This review focuses on in situ preparation methods of inorganic semiconducting nanoparticles in conjugated polymers in view of applications in hybrid solar cells. The details, advantages and disadvantages of the different in situ methods are critically examined and put in comparison to the classical route where pre-synthesized nanoparticles are used. Various key factors influencing the solar cell performance as well as future strategies for increasing the overall efficiency of hybrid solar cells prepared via in situ routes are discussed.

A Non-Oxidative Approach Towards Hybrid Silicon Nanowire- Based Solar Cell Heterojunctions

A general method for the non-oxidative termination of silicon nanowires (Si NWs) is reviewed. Oxide-free Si NW have been successfully alkylated in the lab using a two-step chlorination/alkylation process. The distinctive properties of the resulting Si NW have been taken advantage of by integrating the Si NWs into functional devices such as solar cells. Moreover, molecularly terminated Si NWs exhibit lower defect density emissions than unmodified Si NWs. This, in part, explains the better performance of the molecularly terminated Si NW-based solar cells. Solar cells that use organic-inorganic hybrid Si NWs as absorbers show an increased open-circuit voltage (V

Hybrid Materials – Past, Present and Future.

Hybrid materials represent one of the most growing new material classes at the edge of technological innovations. Unique possibilities to create novel material properties by synergetic combination of inorganic and organic components on the molecular scale makes this materials class interesting for application-oriented research of chemists, physicists, and materials scientists. The modular approach for combination of properties by the selection of the best suited components opens new options for the generation of materials that are able to solve many technological problems. This review will show in selected examples how science and technological driven approaches can help to design better materials for future applications.