Search results for " material"
showing 10 items of 17428 documents
Unravelling the Photocatalytic Behavior of All-Inorganic Mixed Halide Perovskites: The Role of Surface Chemical States
2019
Within the most mesmerizing materials in the world of optoelectronics, mixed halide perovskites (MHPs) have been distinguished because of the tunability of their optoelectronic properties, balancing both the light-harvesting efficiency and the charge extraction into highly efficient solar devices. This feature has drawn the attention of analogous hot topics as photocatalysis for carrying out more efficiently the degradation of organic compounds. However, the photo-oxidation ability of perovskite depends not only on its excellent light-harvesting properties but also on the surface chemical environment provided during its synthesis. Accordingly, we studied the role of surface chemical states …
Degradation of Lincomycin in aqueous medium: coupling of solar photocatalysis and membrane separation
2005
Abstract The photocatalytic oxidation of a common antibiotic, the lincomycin was carried out in aqueous suspensions of polycrystalline TiO 2 Degussa P25 irradiated by sunlight. In order to improve the performance of the lincomycin degradation a hybrid system consisting of a solar photoreactor with the photocatalyst in suspension coupled with a membrane module, used to confine both photocatalyst and pollutants in the reaction environment, was tested. A preliminary study was carried out in order to determine some kinetics parameters of the drug photodegradation. The influence of initial substrate concentration on the lincomycin photooxidation rate was investigated. The photooxidation rate fol…
Hard x-ray photoelectron spectroscopy: a snapshot of the state-of-the-art in 2020
2021
Journal of physics / Condensed matter 33(23), 233001 (1-44) (2021). doi:10.1088/1361-648X/abeacd
Time-resolved core-level photoemission data of tungsten diselenide
2020
Pump-probe core-level photoemission spectroscopy data of tungsten diselenide (WSe2) measured using an electron momentum microscope at the FLASH Free-electron laser.
Photocatalytic Generation of H2 by Photoreforming of Organics in Aqueous Suspension of Nb2o5/C3n4 Composites
2023
Bare and composite materials based on C3N4 and Nb2O5 have been used as photocatalysts for the photoreforming of aqueous solutions of oxygenated compounds. Both Nb2O5 and Nb2O5/C3N4 composites have been prepared by hydrothermal synthesis and all of them were physical-chemically characterized. In this work two different carbon nitride species i.e. graphitic (g-C3N4) or thermo-etched (TE-C3N4) were used both alone or coupled with Nb2O5. The photo-reforming activity has been measured under UV irradiation by using the semiconductors in the presence of Pt as co-catalysts and, in the case of the best material, it was, for the first time, measured and compared also under natural solar irradiation. …
Thin Film CIGS Solar Cells, Photovoltaic Modules, and the Problems of Modeling
2013
Starting from the results regarding a nonvacuum technique to fabricate CIGS thin films for solar cells by means of single-step electrodeposition, we focus on the methodological problems of modeling at cell structure and photovoltaic module levels. As a matter of fact, electrodeposition is known as a practical alternative to costly vacuum-based technologies for semiconductor processing in the photovoltaic device sector, but it can lead to quite different structural and electrical properties. For this reason, a greater effort is required to ensure that the perspectives of the electrical engineer and the material scientist are given an opportunity for a closer comparison and a common language.…
Semiconductors: Growth and Characterization
2018
Semiconducting materials are widely used in several applications such as photonics, photovoltaics, electronics and thermoelectrics, because of their optical and electro-optical features. The fundamental and technological importance of these materials is due to the unique physical and chemical properties. Over the years, numerous methods have been developed for the synthesis of high efficient semiconductors. Besides, a variety of approach and characterization methods have been used to study the numerous and fascinating properties of the semiconducting materials. This book collects new developments about semiconductors, from the fundamental issues to the synthesis and applications. Special at…
Numerical procedures and their practical application in PV module analyses. Part III: parameters of atmospheric transparency – determining and correl…
2023
The presented article examines aspects of a PV module testing using natural sunlight in outdoor conditions. The article discusses the physical sense of indexes: atmosphere purity, diffused component content, beam clear sky index. Procedures for their determination are given in relation to both instantaneous and daily values. Their close connection with the values of solar irradiance spectral distribution such as Average Photon Energyand Useful Fractionis demonstrated, as well as their usefulness in moduletesting in outdoor conditions. Their influence on the conversion of modules made from various absorbers and various technologies is demonstrated
Mixed Stone-timber Masonry in Traditional Construction: Structural, Architectural and Anti-seismic Features across Europe
2018
This paper investigates the stone masonry with timber reinforcement through the European traditional and historical architecture. It is a remarkable practice consisting of combining different materials to build up a masonry. This technology shows a wide variety of typological, formal, and technological types of buildings across Europe as it is strongly influenced by the nature and availability of local materials, the cultural aspects of the various communities, and the soils geological nature. As a consequence, the same constructive typology is based on different premises and leads to many interesting results. In this paper the various uses of such a mixed stone-timber masonry are shown in …
BEM analysis of a piezoelectric structural health monitoring system for delamination detection
2013
In the present work a piezoelectric based structural health monitoring (SHM) system is analyzed with the aim of assessing the ability of the piezoelectric patch to detect both edge and embedded delaminations proper of flange-skin composite laminated structures. he boundary element model is developed for piezoelectric solids and is implemented by taking advantage of the multidomain technique to model laminated and cracked configurations. A non-linear spring model interface is then implemented in conjunction with an iterative procedure allowing for the simulation of the finite stiffness of the bonding layers as well as of the non-penetration condition of the delamination surfaces. he dynamic …