J. Narciso

University of Alicante | UA · University institute of Material

Currently, the production of complex SiC and SiC/SiC parts through reactive infiltration is one of the most widely used technologies, due to its versatility and cost-effectiveness compared to more conventional technologies such as Hot Isostatic Pressing (HIP). This technology, while widely adopted, still faces some debate regarding the mechanisms o...

Metal–organic frameworks have drawn attention as potential catalysts owing to their unique tunable surface chemistry and accessibility. However, their application in thermal catalysis has been limited because of their instability under harsh temperatures and pressures, such as the hydrogenation of CO2 to methanol. Herein, we use a controlled two-st...

The tandem CO2 hydrogenation to hydrocarbons over mixed metal oxide/zeolite catalysts (OXZEO) is an efficient way of producing value-added hydrocarbons (platform chemicals and fuels) directly from CO2via methanol intermediate in a single reactor. In this contribution, two MAPO-18 zeotypes (M = Mg, Si) were tested and their performance was compared...

A new fast, sensitive, and environmentally friendly analytical method has been developed for the simultaneous determination of Ba, Be, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn in wastewater samples using inductively coupled plasma optical emission spectroscopy (ICP OES). A preconcentration step using a magnetic dispersive solid-phase extraction (MDSP...

SiC is one of the most important ceramics at present due to its excellent properties and wide range of applications. The industrial production method, known as the Acheson method, has not changed in 125 years. Because the synthesis method in the laboratory is completely different, laboratory optimisation may not be extrapolated to the industrial le...

Metal–organic frameworks (MOFs) are porous hybrid materials with countless potential applications. Most of these rely on their porous structure, tunable composition, and the possibility of incorporating and expanding their functions. Although functionalization of the inner surface of MOF crystals has received considerable attention in recent years,...

Metal–organic frameworks (MOFs) have drawn attention as potential catalysts owing to their unique tunable surface chemistry and accessibility. However, their application in thermal catalysis has been limited because of their instability under harsh temperatures and pressures, such as the hydrogenation of CO 2 to methanol. Herein, we synthesized Cu...

Zeolitic imidazolate frameworks (ZIFs) have been profusely used as catalysts for inserting CO2 into organic epoxides (i.e., epichlorohydrin) through cycloaddition. Here, we demonstrate that these materials suffer from irreversible degradation by leaching. To prove this, we performed the reactions and analyzed the final reaction mixtures by elementa...

One way to exploit CO2 is to use it as a feedstock for the production of cyclic carbonates via its reaction with organic epoxides. As far as we know, there is still no heterogeneous catalyst that accelerates the reaction in a selective, efficient and industrially usable way. Cobalt and zinc-based zeolitic imidazole frameworks (ZIFs) have been explo...

MIL-100(Fe) is a metal-organic framework (MOF) characterized by the presence of Lewis acid and Fe(II/III) redox sites. In this work, different synthesis methods for the preparation of MIL-100(Fe) are studied. Depending on the source of fluorine, different phases can be obtained: MIL-100(Fe) and an Fe trimesate with unknown structure which we call F...

Metal–organic frameworks (MOF) are a new type of porous materials that have great potential for adsorption of voltaic organic compounds (VOCs). These types of materials composed of metal ions and organic ligands are easy to synthesize, have high surface areas, their surface chemistry can be adjusted to the desired application, and they can also hav...

As previously well-established HTC conferences, the 10 th International Conference on HIGH TEMPERATURE CAPILLARITY aims at issues related to surfaces and interfaces, wetting and capillarity in materials themselves as well as in materials processing and operating at elevated temperatures, including the following tasks: Liquid surfaces of metals, gla...

Silver diamine fluoride (SDF) has demonstrated its clinical success for years in the arrest of caries lesions; however, the influence it could have on the success of restorations after its application still remains unknown. The purpose of this research was to study the relationship between the use of SDF and the adhesive strength of the materials u...

Nowadays one of the biggest challenges for carbon materials is their use in CO2 capture and their use as electrocatalysts in the oxygen reduction reaction (ORR). In both cases, it is necessary to dope the carbon with nitrogen species. Conventional methods to prepare nitrogen doped carbons such as melamine carbonization or NH3 treatment generate nit...

Herein, it has been developed a method to prepare metallic foams starting from Zamak5 (ZnAlCu alloy) with different pore sizes. The Zamak5 metallic foam is designed to serve as a support and metallic precursor of ZIF-8. In this way, composite materials MOF-metal can be prepared, these composites have a large number of application in energy exchange...

The synthesis of MOFs (Metal Organic Frameworks) from reduced metal sources could provide an elegant approach for the recovery of metal waste or to produce MOF coatings on metal or metal alloy surfaces, but this process has not been studied in depth so far. The difficulty of such MOF synthesis lies in the fact that the metal in the MOF structure is...

The preparation of MOFs including a metal with an easily exchangeable oxidation state, while maintaining the same crystal structure and stability, is of paramount importance for myriad applications. In this work, a new synthesis method is reported that can be used to prepare Ce/Zr‐MOFs (UiO‐66 structure) having only Ce(III), a mixed‐valence Ce(IV)/...

This review article is dedicated to the memory of Francisco (Paco) Rodríguez-Reinoso (Granada 1941 - Alicante 2020). Paco dedicated more than 56 years of his life to research on carbon materials, covering from their synthesis and characterization, to their evaluation using a range of processes such as gas adsorption/separation, heterogeneous cataly...

This chapter describes the different approaches that have been developed to synthesize metal organic frameworks (MOFs) with catalytic centres. In general, MOFs are materials composed of an organic and inorganic part, giving them great potential for catalysis. However, many of the stable MOF structures do not have active centres, and these have to b...

Porous SiC with a hierarchical mesoporous structure is a promising material for high‐performance catalytic systems because of its high thermal conductivity, high chemical inertness at high temperature, and oxidation resistance. Attempts to produce high‐surface area hierarchical SiC have typically been made by using porous carbon as a template and r...

Currently, the main challenge facing the development of advanced MMCs and CMCs are related to the costly fabrication of tailored interface microstructures for highly demanding applications. In designing advanced refractory composites, reactive infiltration of liquid Si-enriched Si-Zr alloys into C- or SiC-based preforms may be a cost-less alternati...

Light-weight materials capable of bearing load have become increasingly valuable for designing, construction and assembling of lightweight transportation systems such as aircraft, high-speed trains and satellites. To produce competitive advanced MMCs, SiC- and Cf/C-based composites with desirable properties, the reactive infiltration process has ad...

To succeed in the design and optimization of liquid-assisted processes such as reactive infiltration for the fabrication of tailored refractory SiC/ZrSi2 composites, the interfacial phenomena that occur when Si-rich Si-Zr alloys are in contact with glassy carbon (GC) were investigated for the first time by the sessile drop method at T = 1450 °C. Sp...

Metal Organic Frameworks (MOFs) are a new type of hybrid materials made of metal clusters and organic connectors with a large number of potential applications. Their synthesis is expensive, unclean and requires the use of analytical grade solvents and reagents. It is then desired to develop clean synthesis routes using cheap and easily available pr...

To design and optimize liquid-assisted processes such as reactive infiltration for fabricating refractory SiC/ZrSi2 composites, basic investigations on the interfacial phenomena occurring when liquid Si-based alloys are in contact with C and SiC substrates, are key steps. Indeed, targeted wettability studies may provide helpful indications for find...

SiC is a material with excellent mechanical and thermal properties but with a high production cost. Obtaining SiC by reactive infiltration is an attractive method with a much lower cost than the traditional sintering process. However, the reactive infiltration process presents a serious problem, which is the high residual silicon content, which dec...

SiC is a material with excellent mechanical and thermal properties, but with a high production cost. Obtaining SiC by reactive infiltration is an attractive method and at a much lower cost than the traditional sintering process. However, the reactive infiltration process presents a serious problem, which is the high residual silicon content, which...

Currently, MMCs with SiC as reinforcement emerge as ideal candidates for long-term stable devices withstanding high temperatures and harsh operating environments which are typical for many industrial sectors, such as energy, aerospace, electronics, catalysis, etc. However, the costly manufacture of such composites is the major restraint to make the...

Synthesis of SiC-based composites using microwave(MW)-assisted reactive infiltration is a promising way to obtain these materials at lower costs due to a reduction in processing time and energy consumption. Hot spots are likely to form during this process due to the different dielectric properties of the various phases and the exothermic nature of...

The manufacture of SiC-based composites is quite widespread, and currently different methods are employed to produce them. The most efficient method, taking into account the cost/performance ratio, is reactive melt infiltration. It consists in infiltrating liquid silicon into a porous preform that must contain carbon, so that SiC is produced during...

The manufacture of SiC-based composites is quite widespread, and currently different methods are employed for to produce them. The most efficient method, taking into account the cost/performance ratio, is reactive melt infiltration. It consists in infiltrating liquid silicon into a porous preform that must contain carbon, so that SiC is produced du...

Reactivity between SiC and Ir as a function of SiC-crystallinity was investigated by diffusion bonding technique under a vacuum and over the temperature range of 1200–1450 °C. As reaction products, various Ir-silicides and free unreacted-C were detected. Reactivity is strongly affected by the temperature and SiC-crystallinity involving a series of...

Carbon monolithic adsorbents exhibiting a hierarchical pore structure are produced via a synthesis route based on the stabilization of liquid foams followed by a carbonization step. The macro-microporous structure is achieved by the incorporation of microporous, biomass-derived activated carbon particles in the liquid foam enclosed by a cationic su...

Integration of graphene into electronic circuits through its joining with conventional metal electrodes (i.e. gold) appears to be one of the main technological challenges nowadays. To gain insight into this junction, we have studied the physicochemical interactions between SiC-supported graphene and a drop of molten gold. Using appropriate high tem...

Advanced ceramics such as silicon carbide (SiC) have shown an excellent performance under impact loading, and given their low density, they have attracted attention to be used in personal armor as well as in vehicles. Sintered SiC presents, nevertheless, an elevated cost which is a direct consequence of the severe temperature and pressure condition...

This chapter discusses the impact of vacuum on microstructure and mechanical properties of silicon carbide generated by reactive infiltration. SiC is a ceramic material that has undergone a major expansion of its use in recent years especially in the aerospace and nuclear industry for its excellent properties. Infiltration of the samples was carrie...

This chapter discusses how SiC-ZrSi2 composites were fabricated by reactive melt infiltration of Si-Zr alloys into porous C/SiC preforms in an experiment. The resulting materials were SiC/ZrSi2 composites, in which remaining silicon was considerably reduced by formation of ZrSi2. The composite materials obtained showed an excellent thermal compatib...

The effect of porosity on the thermal conductivity and the coefficient of thermal expansion of composites obtained by infiltration of Al-12 wt % Si alloy into graphite particulate preforms has been determined. Highly irregular graphite particles were used to fabricate the preforms. The thermal conductivity of these composites gradually increases wi...

Remaining silicon in SiC-based materials produced via reactive infiltration limits their use in high temperature applications due to the poor mechanical properties of silicon: low fracture toughness, extreme fragility and creep phenomena above 1000 degrees C. In this paper SiC-FeSi2 composites are fabricated by reactive infiltration of Si-Fe alloys...

Resorcinol-Formaldehyde xerogels are organic polymers that can be easily tailored to have specific properties. These materials are composed of carbon, hydrogen and oxygen, and have a surface that is very rich in oxygen functionalities, and is therefore very hydrophilic. Their most interesting feature is that they may have the same chemical composit...

The knowledge of thermophysical properties of liquid Co-Si alloys is a key requirement for manufacturing of composite materials by infiltration method. Despite this need, the experimental and predicted property data of the Co-Si system are scarce and often inconsistent between the various sources. In the present work the mixing behaviour of Co-Si m...

Remaining silicon in SiC-based materials produced via reactive infiltration limits their use in high-temperature applications due to the poor mechanical properties of silicon: low fracture toughness, extreme fragility and creep phenomena above 1000 °C. In this paper SiC–FeSi2 composites are fabricated by reactive infiltration of Si–Fe alloys into p...

In this work results for the flexural strength and the thermal properties of interpenetrated graphite preforms infiltrated with Al-12wt%Si are discussed and compared to those for packed graphite particles. To make this comparison relevant, graphite particles of four sizes in the range 15-124 μm, were obtained by grinding the graphite preform. Effec...

Among manufacture techniques for SiC ceramics, reactive infiltration has proven to be the most efficient. However, materials manufactured with this technique present minimum 10% of unreacted silicon. Si hinders the performance of the material. The replacement of Si with a MexSiy can improve the performance of the composite. Since Me–Si alloys wet c...

It is well known that there are several processes to manufacture composite materials, a large part of which consist in the infiltration of a liquid (matrix) through a porous medium (reinforcement). To perform these processes, both thermodynamics (wet‐ ting) and kinetics (Navier-Stokes) must be considered if a good quality composite material is soug...

The process of liquid silicon infiltration is investigated for channels with radii from $0.25$ to $0.75$ [mm] drilled in compact carbon preforms. The advantage of this setup is that the study of the phenomenon results to be simplified. For comparison purposes, attempts are made in order to work out a framework for evaluating the accuracy of simulat...

Silicon Carbide (SiC) is one of the most important advanced ceramic, due to its unique set of electrical, optical, thermal and mechanical properties. The main barrier nowadays to wider the use of SiC is its manufacturing process, which requires very high temperatures (above 2000 °C) and pressures (> 100 MPa), is time consuming and allows a non well...

The use of oak sawdust as carbon precursor for SiC manufacture via reactive infiltration was studied. The effect of oak sawdust pressing parameters, temperature and pressure, on the final SiC's properties was studied. Final product's quality was evaluated through density measurement, and microstructure and pore size distribution variations were cha...

Diamond/metal composites are very attractive materials for electronics because their excellent thermal properties make them suitable for use as heat sink elements in multifunctional electronic packaging systems. To enlarge the potential applications of these composites, current efforts are mainly focused on investigating different ways to improve t...

A new family of high thermal conductivity composites, produced through infiltration of a metallic alloy into preforms of mixtures of graphite flakes and either ceramic or carbon materials (in the form of particles or short fibers), has been recently developed. Composites microstructure roughly consists of alternating layers of flakes and metal-part...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The aim of this investigation is to study the mechanism of spontaneous infiltration of AlSi alloys into porous graphite with emphasis on the role of the reaction of carbide formation in the infiltration process. Results are obtained using the sessile drop technique that enables the variation of the infiltration depth with time to be monitored in si...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Two questions of current interest are addressed in this paper: (i) Are contact angles measured by means of the sessile drop technique of any help to understand liquid metal infiltration into solid porous preforms? (ii) To what extent are contact angles derived from either the capillary law or drainage curves valid? These questions have neither simp...

Titanium diboride is being evaluated as a replacement of SiC in metal/ceramic composites for thermal management. Albeit these composites are produced by gas pressure infiltration, no study of the process is available. This work presents an analysis of the threshold pressure for infiltration of Al into TiB2 compacts and of the infiltration kinetics....

The wetting dynamics of silicon carbide forming AlSi alloys on carbon substrates is studied by the dispensed drop technique in high vacuum by varying the parameters: alloy composition, temperature and type of carbon (vitreous carbon, pyrocarbon and pyrographite). The results on wetting are analysed in relation to those on interfacial reactivity and...

Biomorphic SiC components with homogeneous properties were manufactured from sawdust using a novel method to produce preforms, without addition of any extra binder, but with enough mechanical strength to be carbonized up to 1400°C without deformation. Reactive infiltration of carbon preforms of an adequate open porosity with liquid silicon has been...

Aluminium foams with pores displaying both regular size and distribution have been prepared by replication methods. Their volumetric density and electrical conductivity were 0.65gcm−3 and 2.44MSm−1, respectively. This method represents a simple way to produce 3D metal macroporous electrodes. In addition, the aluminium foam has been employed as supp...

Friction force time series showing irregular fluctuations have been since long considered one of the possible stick-slip regimes in sliding friction. However, it has not been until recently that a 1/f power spectrum in friction force time series derived from sliding friction experiments under wear conditions has been identified. A variety of models...

This study is focused on the effect of the porosity and chemical reactivity with silicon of the carbon preforms on the properties of SiC pieces produced by reactive infiltration. Petroleum residues were selected as carbon precursor because of their unique combination of properties. On the one hand, semicoke powders with optimum self-sinterability c...

The effect of porosity (up to 13%) on the thermal conductivity of composites obtained by infiltration of Al–12 wt.% Si alloy into SiC particulate preforms has been determined. The thermal conductivity of these composites gradually increases with the applied infiltration pressure given the inherent reduction in porosity. A simple application of the...

Biomorphic SiC was prepared from four types of Mediterranean wood as carbon precursor. Carbon biotemplates were obtained by pyrolysis and carbonization up to 1400 °C and they were infiltrated with liquid silicon in two different directions. A linear correlation between bending strength and bioSiC density for different types of softwood and hardwood...

It has been shown that the friction force time series in sliding friction under wear conditions is self-similar and has a 1/f power spectrum. Albeit a variety of models, mostly inspired in the field of earthquakes, has been explored, an important factor was overlooked: the role of debris. This Letter describes sliding friction experiments on steel...

The intrinsic permeability k of preforms of packed alpha-SiC particles having monomodal and bimodal particle size distributions has been evaluated by pressureless infiltration of a wetting organic fluid at room temperature. The study was carried out using SiC particles of average diameters in the range 4.88-168 mu m and bimodal mixtures of particle...

The threshold pressure P-0 for infiltration of Al-12 wt.% Si alloy into compacts of mixtures of alumina and silicon carbide particles having largely different size is investigated. The results are in line with those recently derived from infiltrations of Al into bimodal SiC compacts, namely, P-0 remains almost constant for fractions of coarse parti...

Aiming to investigate the role of wettability in the infiltration of tin into graphite particle compacts, sessile drop and infiltration experiments have been carried out at temperatures in the range of 300–700°C. The surface tension of liquid tin and the contact angle at the tin/graphite interface have been measured in an argon atmosphere by means...

The drainage curves (saturation versus applied pressure) that characterize pressure infiltration of Al–12wt.%Si and Al–12wt.%Si–1wt.%Cu alloys into particulate preforms made out of carbon particles of three sizes have been determined. The results show that, no matter the alloy or the particle preform, saturation (pore filling) varies with pressure...

Silicon-doped self-sintering carbons have been prepared by co-pyrolysis of an aromatic petroleum residue with silicon containing compounds (triphenylsilane or diphenylsilane) at 440°C and a pressure of 1.0MPa, with varying silicon content and soak time. Analysis of the solid pyrolysis products indicates that silicon inhibits mesophase formation and...

Threshold pressures for infiltration of different metals into preforms of ceramic particles of various nature and morphology were experimentally determined and the results compared with those estimated by using the specific particle surface areas derived from laser diffraction and gas adsorption. Whilst laser diffraction provides an under estimatio...

Carbon-based/metal composites are materials showing excellent thermal performance. Graphite flakes are attractive carbon-based reinforcements in terms of thermal properties, price and machinability. However, their packed preforms pose insurmountable difficulties to metal infiltration. Here a novel fabrication process is discussed which consists of...

The tribological behavior and lifetime of the lubricating film improvements on material textured by Laser Interference Metallurgy technique have been examined. Commercial stainless steel substrates were prepared matallographically by grinding and polishing with diamond suspensions, followed by a polishing stage using a diamond particle size of 0.05...

Infiltration of reactive NiSi alloys into porous graphite preforms is studied following in situ the variation with time of the volume of a droplet placed on the porous substrate. The shape and depth of the infiltration zone as well as the degree of transformation of carbon to silicon carbide are determined by post-mortem characterizations by scanni...