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The present communication describes the synthesis of anti-slip enamel exhibiting glass-ceramic nature using new matte frits and raw materials. The glass-ceramic glazes obtained are characterized by various instrumental techniques (X-ray fluorescence (XRF), scanning electron microscopy (SEM), X-ray diffraction (XRD), mechanical profilometry and microhardness measurements) to elucidate the nature of the crystallized phases, their morphology, surface roughness and the finished tile microhardness. The quality of the glazed piece is evaluated by the regulations of chemical resistance, stain-resistance and slipperiness. The enamel obtained devitrifies in crystals of calcium and barium silicoaluminates. It complies with anti-slip and stain-resistance standards, because its surface roughness is similar to that of non-slip enamel.

This work describes the synthesis of LaFeO3 oxide, using a one-step hydrothermal synthesis route, to obtain a solid exhibiting superficial, morphological and textural properties useful for potential applications. The synthesis process starts from corresponding metal nitrates of lanthanum and iron in well-defined concentration and KOH as mineralizing agent. The reaction is developed in a Teflon-lined stainless steel autoclave at 300 °C for 14 days. The composition and surface area were determined with X-ray fluorescence (XRF) and nitrogen adsorption isotherms (BET), verifying the obtaining of a stoichiometric, high, and active phase of oxide. The crystalline structure was evaluated with X-ray diffraction analysis (XRD), showing a pure orthorhombic perovskite phase. TPR results show the development of three single steps at different temperatures, kinetically detectable and related with reduction of component oxides. Scanning and transmission electron microscopy (SEM-TEM) results showed a remarkable degree of crystallization, favouring a specific morphology as a result of the low consolidation temperature of the perovskite phase. Catalytic test by means of methane reaction, performed along 240 on stream, reveals a light deactivation rate, decreasing progressively 7.1% until 60% of methane conversion, indicating the improved morphological and surface characteristics for potential applications.

Nota póstuma dedicada a la Profesora Purificación Escribano López, Catedrática de Química Inorgánica en la Universitat Jaume I de Castelló. El artículo repasa los aspectos más relevantes de su obra y de su trabajo como docente e investigadora en la universidad de Castelló.

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2020/2021 The development of new glass-ceramic tiles by sinter-crystallization method have been investigated using solid wastes (ceramic polishing, soda-lime-silicate glass, eggshell, mussel shell and industrial sludge’s). Chemical compositions of wastes and glass-ceramic samples were studied by X-ray fluorescence (XRF) and thermal analysis (TG/DSC). Structural characterization by X-ray diffraction (XRD) measurement revealed the crystalline phases depending on process parameters. The morphology of glass ceramic samples was characterized by scanning electron microscopy (SEM/EDX). The apparent density values were between 1,47 and 1,79 g/cm3 . Flexural strength values range between 52,09 and 97,76 N/mm2 . The experimental compositions allowed reutilizing residues to produce high mechanical resistance glass ceramic tiles with suitable properties and environmental profits.

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2019/2020 Pyrochlores are widely studied for their variety of properties according to their composition, hence their versatility. In this bibliographic work, the study of nanopigments with pyrochlore structure with luminescent properties is shown. It focuses on a wide range of theoretically based introductions of pigments, pyrochlore structure and luminescence. Specifically, Eu 3+ doped Gd2Ti2O7 is studied, comparing three methods of synthesis: sol-gel, Pechini and solid state. Finally, the experimental results are proposed through the application of X-Ray diffraction (XRD), Thermogravimetry/Differential Thermal Analysis (TG/DTA), Scanning Electron Microscopy (SEM) and Photoluminescence spectrocopy. Detailed description of each procedure step and discussion of the obtained results have been performed along the project. Additionally, a bibliographic search and description of main theoretical concept on pigments, together with analysis of State of art of inorganic pigments have been performed. Some possible application of the developed materials is proposed.

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2019/2020 Over the last years, an increasing concern has emerged regarding the eco-friendly management of plastic, glass and ceramic waste. Nowadays, the world economy remains heavily dependent on primary resources, which are becoming increasingly scarce on the basis of the current lineal economy model. For this reason, it is essential to evolve towards a circular economy and the recycling of waste. In recent years, composite materials have experienced a rapid growth in their development and use until becoming a commonly material in our daily live and replacing many conventionals materials such as metals, ceramic or polymers. This is due to the advantages that they can offer. The principal objective of fiber-reinforced composite is to acquire materials with high strength and high elastic modulus /stiffness. In this work, composite materials are formed by a ceramic matrix and a glass fiber or plastic fiber reinforcement. Several porcelain stoneware tile compositions are prepared using volume fraction between 5% and 75% of wt funcionalizate glass fibers. Then, the composition is examined. Previously, fibers were functionalizate by a mullite synthesis. The optimal treatment for mullite phase formation and higher mechanical resistance for ceramic material are obtained. Structural characterization of funcionalizate glass fibers and recycled plastics are studied with Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) by using X-Ray diffraction (XRD) and Scanning Electron Microscopy (SEM) and Differential Thermal Analysis/Thermogravimetric (ATD/TG).

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2018/2019 Transparent conductive oxides (TCO) are doped metal oxides used in optoelectronic devices such as flat panel displays and photovoltaics. In the present work, zinc oxides are doped with different metals (aluminium, silver, lithium, indium and gallium).These compounds have been synthesized by co-precipitation method starting from different precursors. The obtained powders have been deposited by spin coating technique and further heated in a muffle. During the preparation process, the influence of several parameters has been evaluated, e.g. the number of layers while doing the deposition process or heating cycle. The obtained coatings have been studied by applying X-Ray diffraction (XRD), Scanning Electron Microscopy (SEM), UV-visible and IR spectroscopy. Detailed description of each procedure step and discussion of the obtained results have been performed along with the project.

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2018/2019 iber composite materials have great applications for the building and construction industries. The main objective of fiber-reinforced composites is to obtain materials with high strength together with a higher elastic modulus. In this work, composite materials of fibers were built as reinforcing agents in slip as a ceramic matrix. Fiber volume fractions between 5% and 20% were examined. For the preparation of several compositions of porcelain stoneware tiles, the fibers were first conditioned for later mixing with the slip. It has been evaluated the effect provided by each of the agents mentioned above, within the matrix in improving the mechanical properties of fiber-reinforced material. The resulting materials were studied by scanning electron microscope (SEM), flexural strenght mesuraments, particle size evaluation and colorimetry analysis.

El sistema productiu mundial actual és incapaç de garantir la continuïtat de l’existència de les matèries primeres de nova extracció en un futur llunyà. És per això, que cada volta és més necessària la reintroducció dels residus materials de nou en la cadena de producció i evolucionar cap a un sistema d’economia circular. Els materials vitroceràmics reciclats són materials d’alt valor afegit que resulten idonis per a la immobilització de residus, que no només suposen un rebuig industrial que cal gestionar sinó que, a més, representen uns importants agents contaminants del medi ambient que poden resultar tòxics o perillosos per a la salut. A part, la reintroducció de residus permet un abaratiment dels costos de producció. En segon lloc, degut a la sempre constant evolució de la indústria s’ha proposat l’aplicació de recobriments intel·ligents sobre els suports vitroceràmics amb la finalitat d’aconseguir materials amb noves funcionalitats que es troben a l’avantguarda de l’evolució tecnològica. Així, en aquest treball es proposa la síntesi de materials vitroceràmics a partir de matèries primeres basades en el vidre reciclat i en residus industrials com les cendres volants de centrals tèrmiques o els residus de polidora, mitjançant un procés de sinter-cristal·lització, i la seua posterior caracterització. A més, s’ha sintetitzat i aplicat un pigment fosforescent d’aluminat d’estronci dopat amb europi i disprosi i s’ha recobert el suport vitroceràmic amb diferents recobriments per generar una cèl·lula solar de calcogenurs.

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2017/2018 Mullite has achieved outstanding importance as a material for both traditional and advanced ceramics because of its favourable thermal and mechanical properties. Mullite displays various Al to Si ratios referring to the solid solution Al4+2xSi2−2xO10−x, with x ranging between about 0.2 and 0.9 (about 55 to 90 mol% Al2O3) [1]. In this work, the functionalization of the recycled glass fibers (obtained from the glycolysis process) with mullite crystals and its introduction into the precursor composition of the ceramic substrate was proposed. Mullite were first prepared by sol-gel method using colloidal silica and AlCl3·6H2O in water system. The gel mullite precursor was fired in the range 1000-1300ºC soaking times 30–300 min. The resultant materials were studied by X-Ray diffraction (XRD) and scanning electron microscope (SEM-EDX). On the other hand, the glass fibers were functionalizing through the previous mullite synthesized. Several porcelain stoneware tile compositions were prepared using high alumina clay, low alumina clay, kaolin, Turkish feldspar (Na), feldspar (Na/Mg), feldespathic sand and glass fiber functionalize. The resultant materials were studied by X-Ray diffraction (XRD), scanning electron microscope (SEM-EDX) and compressive test. High mechanical resistance ceramic material (> 450 Kg/cm2) was obtained

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2016/2017

Treball Final de Grau en Química. Codi: QU0943. Curs acadèmic: 2016/2017.