Miguel A. Rodriguez

Spanish National Research Council | CSIC · Department of Ceramics

Ytterbium ferrites are being used in many promising applications, such as visible-light photocatalysis, solar cells, magnetooptic devices, electro-magnetic equipment, etc., due to their fantastic ferroelectric and ferromagnetic properties. However, despite their good magnetic and radiopaque features, the use of ytterbium ferrites as multiplatform c...

Perforated stone plaques, known as bracers, are found across late prehistoric Europe and many of them have been recovered in Bell Beaker funerary contexts, usually associated with adult individuals. Experimental, technological, and use-wear studies have determined that the bracers were both utilitarian and symbolic objects. Very few are found in ch...

The elderly population (65 years and older) is expected to increase from 524 million people in 2010 to 1.5 billion by 2050, with the corresponding increase in bone-related and joint damage problems. Many of these problems can be solved by using scaffolds for bone tissue regeneration, and material selection is a critical step to obtain satisfactory...

A novel pathway for the magnesiothermic reduction of boron oxide and magnesium dodecaboride (MgB12) in the presence of carbon by a self-propagating high-temperature synthesis method was proposed that was aimed at the direct preparation of boron carbide nanopowder. The combined utilization of two boron sources, boron oxide and MgB12, allowed tailori...

Teeth provide information about the evolutionary pathway of an organism, its biology and habitat. This is the case even of fossilized teeth, since they have perdurable biomineralized structures, as biological apatite. The material that has been selected for this study comprises teeth from modern crocodilian individuals and extinct Cretaceous crocod...

The photocatalytic behaviours of semiconductive ceramic nanoparticles such as TiO2, ZnO, Fe2O3, and Fe3O4, have been extensively studied in photocatalysis and photopolymerization, due to their ability to produce radical species under ultraviolet visible light, and even in dark conditions. In addition, in the form of microparticles, TiO2 and its Mag...

Low cost asymmetric tubular ceramic membrane was developed from kaolino‐illitic clay collected from the region of Medenin (Tunisia). The obtained membrane was designed to be used for ultrafiltration. The effect of pore forming agent on the plasticity, porosity, pore size distribution, mechanical strength and permeability was evaluated. The support...

Abstract The objective of this work was to produce brushite cement for orthopedic applications, based on the system wollastonite/phosphoric acid with the incorporation of polyethylene glycol (PEG) as a setting and processing additive. Brushite/PEG cement was obtained by the dissolution-precipitation method and its physicochemical properties were ch...

In order to provide favorable conditions for bone regeneration, a lot of biomaterials have been developed and evaluated, worldwide. Composite biomaterials have gained notoriety, as they combine desirable properties of each isolated material. Thus, in this research, bone repair capacity of three developed formulations of ceramic scaffolds were evalu...

Bimetallic nanoparticles have gained vivid attention due to their unique and synergistic properties. They can be used in fields such as solar cells, optics, sensing, as well as medicine. The generation of bimetallic nanoparticles, containing oxide phases of both magnetic and X-ray attenuating metals for bioimaging applications has been challenging...

Synchrotron radiation X-ray microdiffraction (SR-μXRD) has been applied for the first time as a fundamental method of analysis to unveil crocodilian teeth growth and development. Teeth from a fossil crocodylomorph from the Upper Cretaceous site of Lo Hueco (Spain) and a modern crocodylian from the living species Crocodylus niloticus have been analy...

Olivine based cathodes with a chemical formula of LiMn1−xMxPO4 (where M = Fe, Ni, Co…) are considered as a potential candidate with their viability of high voltage applications, improved stability against various battery components and ambient conditions. However, the technology for scaling up the material synthesis remains a challenge. Solution co...

In this study, tubular ceramic membranes were prepared from a mixture of ball clay, talc and alumina. The mixture was characterized by the following techniques: particle size analysis, X-ray fluorescence spectroscopy (XRF), X-ray diffraction (XRD) and thermal analysis. Tubular membranes were produced by extrusion process and thermal treated at temp...

This study focused on the development and preparation of a microfiltration membrane, based on a low-cost natural Tunisian clay powder, deposited on macro-porous ceramic support. The deposit was made through a dip-coating technique, followed by a drying process and sintering at 700 °C. Results revealed that the obtained membrane was characterized by...

This study aims to investigate the effects of adding CaSiO3–Ca3(PO4)2–MgCa(SiO3)2 eutectic glass on the sinterability, microstructure, and mechanical properties of CaSiO3–Ca3(PO4)2 bioceramics. The CaSiO3–Ca3(PO4)2 (80/20 wt%) bioceramics with 30 vol% CaSiO3–Ca3(PO4)2–MgCa(SiO3)2 eutectic glass sintered at 1245 °C for 4 h showed a biaxial flexural...

This work focuses on dip coating and further phase inversion prepared polysulfone/LTA zeolite mixed matrix membranes (MMMs). The Linde Type A (LTA) ze-olite synthesized under hydrothermal conditions by the organic free method was introduced as fillers at 10 and 20 wt.% loadings into the polysulfone polymer matrix to obtain MMMs. The x-ray diffracti...

The irruption of additive manufacturing techniques opens the possibility to develop three-dimensional structures with complex geometries and high precision. In the current investigation a newly designed composite combining silicon (30, 40 and 50 wt%) with a bioactive glass and printed into scaffolds was obtained, using a direct selective laser melt...

The scaffolds, which morphologically and physiologically mimic natural features of the bone, are of high demand for regenerative medicine. To address this challenge, we have developed innovative bioactive porous silicon- wollastonite substrates for bone tissue engineering. Additive manufacturing through selective laser melting approach has been exp...

In this work, a new family of multiphasic materials composed of the same amount of silica gel and variable amount of three calcium phosphates with very different solubilities, monetite > amorphous calcium phosphate > hydroxyapatite (HAp), was studied. Silicon was added to calcium phosphate to increase bioactivity and osteinductivity. The influence...

Scaffolds are models designed to aid the interaction between cells and extracellular bone matrix, providing structural support for newly formed bone tissue. In this work, wollastonite with β-TCP porous ceramic scaffolds was developed by the polymer sponge replication. Their microstructure, cell viability and bioactivity were tested. in vivo was per...

This study presents experimental data of the interactions and reactions that occur during the early stages of the growth of ZnO on graphene supported on polycrystalline copper and the subsequent changes on the electronic properties of the graphene. The combination of substrate, graphene, and intercalated species (such as oxygen and water molecules)...

In this article a review of the use of Calcium phosphates in Biomedical Engineering has been done. A brief revision of the first applications in the field of medicine of these phosphates is carried out, to later comment on the current situation. The different types of existing calcium phosphates are summarized and where they are applied in the fiel...

a-TCP microspheres were obtained by atomizing aqueous slurries containing 50 wt% of low crystallinity α-TCP and 1 wt% of citric acid. Poly(ethylene glycol) and poly(vinyl alcohol) were tested as a binder. The spray drying process yielded to microspheres with mean diameter around 20 μm and sphericity (horizontal and vertical length ratio) closest to...

The thermal evolution of a vitreous biomaterial based on the CaSiO3 – Ca3(PO4)2 – MgCa(SiO3)2 system has been studied. The crystallization kinetics and the devitrification capability were analyzed using Differential Thermal Analysis and X- ray diffraction. Powders with two different particle sizes (300–500 µm and <45 µm) were used for kinetic studi...

In this study, the viscosifiers for diesel oil drilling fluid were prepared using Tunisian clay modified with cationic surfactant for five concentration levels from 0.5 to 4.0 times the cationic exchange of purified clay (CEC). The organo-modified clay samples were characterized by X-ray diffraction (XRD), Infrared spectroscopy (FTIR), scanning ele...

A synthetic gibbsite (Al(OH)3) produced by the Bayer process was mechanically activated by attrition milling for 24 h with various grinding ball-to-powder ratios (BPR = 5, 10 and 20). Changes in its structure were studied by thermal analysis and X-ray diffraction. As a result of increasing ball-to-powder ratio, the grain size of gibbsite decreased...

Phospho-olivine pristine LiMnPO4/C and yttrium-substituted LiMn1–xYxPO4/C (x = 0, 0.01, 0.03, 0.05) were synthesized by a solution combustion method. The effects of Y-doped on structure, morphology and electrochemical performances were investigated. From powder X-ray diffraction pattern, all substituted materials adopt an identical structure to tha...

Engineered bone tissue or scaffold is a potential alternative to the common use of bone grafts due to limitless supply and no disease transmission. We present a novel way to manufacture the highly efficient bioceramics combining osteoinductive and bioactive elements using additive manufacturing through selective laser melting without polymer based...

Twelve left humeri from non-adult human individuals were selected from the Hispano Muslim collection of San Nicolás (Murcia, Spain), a cemetery (maqbara) dating from the 11th to 13th centuries. All burials followed the Muslim funerary rite (simple, with the body deposited on its right lateral side directly in contact with the sediment and oriented...

This study has focused on the development of porous materials from representative Tunisian clay. The first step was the characterization of the clay through powder X-ray diffraction (XRD), thermal analysis and evaluation of its plasticity. With this data, an extrusion paste was prepared, mixing the clay with 26% water. This paste was extruded in th...

Currently Mineral Trioxide Aggregate (MTA) is extensively used in Endodontics for Root Canal Treatment. It mainly consists of Portland cement and radio-opacifier agent. In spite of being widely used with success, there are some concerns regarding its properties. The objective of this study was to employ strontium and calcium aluminates to formulate...

Quartzite is a mineral that contains oxides that are present in the principal raw materials utilized in traditional ceramic production. However, during its extraction and processing, large amounts of waste are generated. This study, therefore, sought to investigate the incorporation of quartzite waste into the ceramic mass, replacing up to 25% of t...

The catalytic effect of metal oxide/alumina whiskers (CeO 2 , Mn 3 O 4 , NiO, Co 3 O 4 , Fe 2 O 3 , Cr 2 O 3 /AW) was evaluated on their ability to drive the nitridation of silicon and to generate mesoporous fibrous silicon networks. Silicon powder with different particles size along with the catalyst was nitridized at 1300 °C for 5 h in nitrogen a...

Surfaces of Tunisian montmorillonite clays were modified using batch method through intercalation of cationic surfactant hexadecylpyridinium (HDPy⁺) by an exchange reaction. The structural, textural and surface properties of clays, before and after modification, were investigated using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscop...

Three dimensional graphene-hydroxyapatite (3DG-HA) powders were synthesized at various hydrothermal pressures and the effect of pressure change on the properties of the powder was investigated by the change in the volume of the solution. Graphene oxide, calcium nitrate tetrahydrate, and diammonium hydrogen phosphate solutions were used as a precurs...

In this study, in situ formation of three dimensional graphene-hydroxyapatite using graphene oxide, calcium nitrate tetra hydrate, and diammonium hydrogen phosphate solutions in a chemical synthesis system was investigated. First, the solutions were mixed and calcium phosphate was precipitated on graphene oxide sheets followed by performing a hydro...

The hydroxyapatite (HAp) is a ceramic biomaterial with wide application in the bone regeneration. It can be obtained by different routes and different precursors. In this study, the synthesis of HAp was carried out by precipitation and subsequent thermal treatment using different calcium precursors: calcium hydroxide from synthetic origin and calci...

Silicon-calcium silicate scaffolds were fabricated by selective laser melting (SLM). Rectangular composite scaffolds with a pore size of 400 µm were designed with dimensions of 10 × 20 × 5 mm 3. For imparting controlled drug release capability, scaffolds were covered with polycaprolactone (PCL) coatings for the sustained delivery of vancomycin. The...

The objective of this work has been the synthesis of wollastonite by solution combustion method. The novelty of this work has been obtaining the crystalline phase without the need of thermal treatments after the synthesis. For this purpose, urea was used as fuel. Calcium nitrate was selected as a source of calcium and colloidal silica served as a s...

In this paper the synthesis by solution combustion (SCS) of tri‐strontium aluminates (Sr3Al2O6), using different fuel amounts, has been studied. The main objective was to understand the effect of the amount of fuel on phase formation, yield and purity of the product using urea as fuel. The combustion temperatures of each reaction were followed by d...

The aim of this work was to perform an analysis of the influence of Sodium Fluoride (NaF) on chitosan particles size and morphology produced via ionotropic gelation with higher rotational stirring speed. Samples were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Dynamic Light Scattering (DLS), Zeta Potential (ζ), Scanning Electro...

This work presents the photopolymerisation of composite scaffolds where a prefabricated ceramic scaffold was impregnated with poly(ethylene) glycol dimethacrylate (PEGDMA) macromonomer solution. The PEGDMA solution penetrates the porosity of ceramic scaffold where it cures in situ thereby enhancing their mechanical properties. The mechanical proper...

Mesoporous networks with a special distribution of functional centers are an important class of high performance materials for catalysts, bioscaffolds, energy conversion and storage systems. Methods of fabrication allowing to control over special distribution of the functional sites of required phases and designed morphology are still of a great ch...

In this study, we present a simple and effective process that integrates hydrogels with drugs + ceramics via physical crosslinks resulting in improved mechanical properties. These cryogels have the potential for controlled drug release and stimulus responsive behavior. The hydrogels were produced from polyvinyl alcohol (PVA) and polyacrylic acid by...

Additive manufacturing is gaining increasing attention as it provides cost-effective and waste-less production of materials with multi-axis geometries. Selective laser sintering of ceramics is very challenging in terms of poor sinterability caused by low thermal shock resistance and insufficient electron conductivity blocking absorption of laser be...

Calcium phosphate cements (CPC) have been widely investigated as bone graft substitutes due to its excellent self-setting ability, biocompatibility, osteoconductivity and moldability. In additional, mesoporous materials have also been studied as potential materials for application in medical devices due to their large surface area, which is capable...

Activities on SHS began in Spain in 1991 with a joint project. The aim was to produce a pilot plant for production of powders by SHS and evaluate their quality and production costs. Spanish centers have been part of multinational teams that have developed collaborative projects within the European Union and other countries. Currently, the work on c...

In the present paper we report the synthesis, structural characterization and catalytic properties of alumina nanofibers supported Ni-CeO2 catalyst (Ni-CeO2/ANF) in pre-reforming of propane as a main component of liquefied petroleum gas. Ni-CeO2/ANF catalyst was prepared via template-assisted wet-combustion synthesis. High dispersion and uniform di...

Low cost asymmetric membranes have been prepared from natural materials. The flat ceramic supports were elaborated from natural kaolino-illitic clay using olive pomace as a pore forming agent. The effect of sintering temperature and pore forming agent on the mechanical strength, porosity, pore size distribution and permeability were evaluated. It w...

Objectives: First ribs bear information about thorax morphology and are usually well preserved, compared to other ribs, in bone/fossil samples. Several studies have addressed ontogeny of the first rib by studying changes in bone microanatomy and rib morphology separately, but no studies have combined both approaches to study how internal and extern...

Human first rib morphology provides important information concerning thorax anatomy from both ontogenetic and phylogenetic perspectives. Luckily, they frequently appear well preserved in the archaeological/fossil record and are easy to assess in commingled samples because of their unique anatomy. Regarding first rib ontogeny, several studies have a...

We herein hypothesize that bioceramics with an appropriate architecture made ofSi-αtricalcium phosphate (Si-αTCP) meet the biocompatibility and biological safety requirementsfor bone grafting applications. Polyurethane sponges were used as templates, soaked with ceramicslurry at different ratios and sintered at 1400 °C for 3 h at heating and coolin...

The aim of this review is to present the progress in preparing phosphorescent particles based on the reported research. We highlight the recent progress on SrAl2O4: Eu, Dy particles by describing the advantages and disadvantages of the different synthesis methods. This long-lasting material combines several favorable attributes: is stable, efficien...

This study was developed based on in vivo investigation of microporous granular biomaterials based on calcium phosphates, involving matrices of β-tricalcium phosphate (β-TCP), hydroxyapatite (HA), biphasic compositions of both phases and a control group. The physicochemical characterization of materials was carried out by X-Ray diffraction (DRX) an...

The history of calcium phosphates in the medicine field starts in 1769 when the first evidence of its existence in the bone tissue is discovered. Since then, the interest for calcium phosphates has increased among the scientific communities. Their study has been developed in parallel with new advances in materials sciences, medicine or tissue engin...

One of the reasons of implants failure is the stress forces appearing in the material–tissue interface due to the differences between their mechanical properties. For this reason, similar mechanical properties to the surrounding tissue are desirable. The synthesis of hydroxyapatite by solution combustion method and its processing have been studied...

The synthesis of AlN and TiB2 by spark plasma sintering (SPS) and the effect of Nb2O5, Y2O3 and ZrO2 additions on the mechanical properties and densification of the produced composites is reported and discussed. After the SPS process, dense AlN and TiB2 composites with Nb2O5, Y2O3 and ZrO2 were successfully prepared. X-ray diffraction analysis show...

A novel wet-combustion method is developed to functionalize mesoporous network of alumina nanofibers. The wet-combustion method includes coating the nanofibers with the solution of the precursors of dopants mixed with fuels, followed by dissociation/oxidation of the precursors in a combustion mode. Due to the high temperature of the flame and short...

Novel type of hybrid nanofillers representing graphene encapsulated alumina nanofibres was selected as an additive to develop toughened electroconductive partially stabilized zirconia. The sinterability, mechanical and electrical properties of the produced nanocomposites were studied as function of the filler/graphene content. Composites containing...

In this work we have studied the plasma removal of air contaminants such as methane, chloroform, toluene and acetone in two parallel plate packed-bed dielectric barrier discharge (DBD) reactors of different sizes. Removal and energy efficiencies have been determined as a function of the residence time of the contaminated air within the reactor, the...

Porous ceramic supports were elaborated from natural kaolino-illitic clay, before and after acid activation, using uniaxial dry pressing method. The prepared supports were sintered at 850, 900 and 1000 °C. The effect of sintering temperature on the mechanical strength, density, porosity, pore size distribution and permeability was evaluated. It was...

This aim of this research was to develop a novel ceramic scaffold to evaluate the response of bone after ceramic implantation in New Zealand (NZ) rabbits. Ceramics were prepared by the polymer replication method and inserted into NZ rabbits. Macroporous scaffolds with interconnected round-shaped pores (0.5-1.5 mm = were prepared). The scaffold acte...

The design of phosphorescent materials, highly crystalline, with a submicron particle size is a challenge for industrial applications. Based on molten salt assisted process, the effects of salt/SrAl2O4 molar ratio on the phase evolution are studied. A significant influence of salt/SrAl2O4 molar ratio on synthesis and final properties has been obser...

High affinity and adhesion capacity for Gram-positive bacteria on minerals has been widely studied. In this work the adhesion of bacteria on synthesized zeolite has been studied. The Zeolite Linde Type A (LTA) has been synthesized using hydrothermal route using processing parameters to obtain low cost materials. For adhesion studies _Staphylococcus...

Multimodal diagnosis by combining mammography, MRI and X-ray CT techniques, such as play a leading role in the diagnosis of breast cancer. [1] However clinical application of this multimodal approach is problematic due the lack of commercial contrast agents showing capabilities to distinguish between malignant tumours and benign abnormal masses. Hy...