Browsing by Author "Anunziata, Oscar A."

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Direct synthesis and characterization of mesoporous carbon CMK-3 modified with zirconia applied in energy storage
(2020) Venosta, Lisandro F.; Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.
In this work, we report the synthesis and characterization of the nanostructured carbon material (CMK- 3) modified with zirconium oxide synthesized by a new direct synthesis technique. The aim of this new synthesis method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. Zirconium oxide dispersed in carbon materials (Zr-CMK-3) were successfully synthesized and characterized by X-ray diffraction, textural properties, UV-Vis-DRS, XPS, and transmission electron microscopy analysis. This material is promising in the application of hydrogen adsorption for energy storage. Zr-CMK-3 material significantly improved H2 storage behavior (4.6% by weight at 77 K and 10 bar) compared to CMK-3 support. The synthesized material is promising in the absorption of hydrogen by weak bonding forces (physisorption). A hydrogen adsorption mechanism was proposed and the role of the Zr+4 cation in hydrogen absorption was discussed. The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction) [1]. The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The interaction of the induced dipole in a second layer adsorbs more hydrogen molecules because the strong interaction of the metal particles takes up dipole-induced forces on the hydrogen molecules. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases. The procedure for this adsorption is still under investigation and optimization. The hydrogen storage behavior in Zr-CMK-3 can be optimized by controlling the size of the metal particles, the dispersion and the nature of the support.
Green hydrogen from catalytic ammonia decomposition
(2021) Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.
Ir/γ-alumina catalysts for decomposition of ammonia were prepared by Iridium ion exchange procedure, onto γ-alumina synthesized by sol-gel method. In order to determine the physical and chemical properties we used X ray diffraction (XRD) analysis, Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR-MAS). The samples displayed the characteristic band at 1620 cm-1 corresponds to a N-H bending of ammonia adsorbed on electron-acceptor sites, and the characterization by pyridine adsorption and desorption to determine the presence of Lewis acid sites, with absence of Brønsted sites, showing higher acid strength than commercial sample used as reference. The analysis of particle size and morphology reveal uniformity, with tendency to a spheroid aspect and smaller to 3 μm of diameter. The 27Al NMR-MAS test, allowed determining the tetrahedral and octahedral aluminum presence in both samples, where the higher proportion of octahedral Al in γ-alumina synthesized by us, is correlated toward the greater electron acceptor acid sites. The designed method was effective for Ir/γ-alumina catalysts synthesis. The surface area was 150 and 260 m2/g for the commercial sample and the alumina prepared by and us, and after the Ir incorporation (10-18% w/w in both samples), they surfaces were reduced approximately 5.4-8.8% and 4.3-7.2% respectively. XRD analyses show the absence of maximums at 28º and 34.7º 2 corresponding to iridium oxide, indicating a high efficiency of the reduction treatment, increasing the active sites for the specific reaction of ammonia decomposition. The distribution of the Ir crystallites determined by XRD and TEM indicated that, the samples prepared by ion exchange method produced smaller Iridium clusters than by impregnation procedure of alumina sample, with higher surface area and greater anchorage sites. According to preliminary catalytic tests, the Ir/γ-alumina catalysts prepared by a novel method showed higher activity to ammonia decomposition to N2 and green H2.
HaP / LP-SBA-15 Nanocomposite for efficient removal of fluoride from contaminated wáter
(2020) López, Claudia G.; Anunziata, Oscar A.; Cussa, Jorgelina
Hydroxyapatite (HaP) composites and highly ordered large pore mesoporous silica, such as LP-SBA-15 (Large Pore-SBA-15), were developed, characterized by XRD, BET, FTIR and HRTEM, and applied properly to fluoride removal from contaminated water. The proposed procedure to prepare HaP/LP-SBA-15 was successful, which acts as supports to anchor the HaP crystals, in nanometer-scale (<12 nm), with higher fluoride retention from contaminated water. The free OH- groups of HaP nanocrystals, inside the host, permitted fluoride retention with high capacity. The fluoride holding activity was over 3 orders of magnitude higher than pure HaP.
Hydrogen storage on a novel nanostructured carbón material modified with zirconia
(2021) Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.; Venosta, Lisandro F.
In this work, we report the synthesis and characterization of zirconium oxide supported in nanostructured carbon material synthesized by a new direct synthesis technique. The goal of this new method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. The material with zirconium oxide (Zr-CMK-3) was successfully synthesized and characterized by Xray diffraction, SEM, RAMAN and textural properties, UV-Vis-DRS, X-ray photoelectron spectroscopy and transmission electron microscopy analyses. Zr-CMK-3 improved significantly the H2 storage behavior (4.6 wt% at 77 K and 10 bar) compared with CMK-3. The synthesized material is promising for hydrogen uptake by means of weak bonding (physisorption). The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction). The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases.
Mesopore carbón starch with acid properties: synthesis and characterization
(2020) Martínez, María Laura; Anunziata, Oscar A.
We have shown that a promising material with acidic properties can be successfully prepared from starch mesoporous carbon (SMC), functionalized with sulfated zirconia. The process of assembling P123, starch, zirconia, and silicon synthesized Zr-modified ordered mesoporous carbon. SMC and Zr-SMC were characterized by BET for their texture properties and, using Scanning Electron Microscopy (SEM), their morphology. Acidic properties were acquired by programmed thermodesorption of ammonia (NH3 TPD). These studies show that the Zr-SMCs material is mainly composed of mesopores with an average pore size of approximately 3.5 nm, high surface area and pore volume, and has medium to strong acidity properties.
Mesoporous carbon cmk-3 modified with zirconia developed by direct synthesis technique applied in energy storage
(2021) Gómez Costa, Marcos B.; Juárez, Juliana M.; Venosta, Lisandro F.; Anunziata, Oscar A.
Nanostructured carbon material (CMK-3) modified with zirconium oxide was synthesized by a new direct synthesis technique. Zirconium oxide dispersed in carbon materials (Zr-CMK-3) were characterized by X-ray diffraction, textural properties, UV-Vis-DRS, XPS, and transmission electron microscopy analysis. The goal of this new synthesis method is to avoid the use of inorganic siliceous template (SBA-15), which leads to a shorter and cheaper way to obtain mesoporous carbon, and at the same time incorporate into the framework Zirconium atoms. Zr-CMK-3 material significantly improved H2 storage behavior (4.6% by weight at 77 K and 10 bar) compared to CMK-3 support. The synthesized material is promising in the absorption of hydrogen by weak bonding forces (physisorption). The activity of the samples to the adsorption of hydrogen molecules is attributed to the improved dispersion of the zirconium oxide, as well as the appropriate use of support, which can probably disperse the zirconium on its large surface area, allowing a great dispersion of the zirconium. The Zr+4 cation is an active species to absorb and store hydrogen through a physisorption process and the carbon plays an important role in the dispersion and size of metal particles. A hydrogen storage mechanism on the active surface of the ZrO2 clusters was proposed. First layer of hydrogen molecules can react with the metal cation through a dihydrogen complex (Kubas interaction). The second layer of hydrogen molecules adsorbed around the metal oxide clusters is due to dipole-like interactions, this is because the metal particle induces dipole forces on the hydrogen molecule. The other layers could also interact by dipole forces; however, the interaction force decreases as the distance to the surface increases. The upper layers could interact with the metal cation by dipole-induced bonding; however, the interaction force decreases as the distance to the surface increases.
Mesoporous sulfate-zr-carbon nanomaterial: a new chemically active species.
(2021) Anunziata, Oscar A.; Martinez, María L.
In this work, we report the successful preparation of a nanomaterial with acidic properties from sulfated zirconium functionalized mesoporous carbon (SZr-MC). SZr-MC presents a new chemical species formed by bonding Carbon with sulfated Zirconium (Zr): C-O-Zr- H2SO4 and C-Zr (H2SO4)-C. It has a surface area of approximately 1300 m2 g-1, and a total pore volume of 0.94 cm3g-1, composed mainly of mesopores with an average pore size of 3.5 nm. The surface composition and chemical states of the elements did not reveal that ZrO2 was an isolated cluster. A new nanomaterial based on mesoporous carbons modified with sulfated Zr was developed, which opens up a wide range of acid-catalyzed reactions applied to biomedical engineering.
Multiple-wall carbón nanotubes obtained with mesoporous material decorated with cerio-zirconium
(2020) Martínez, María Laura; Anunziata, Oscar A.
In this work, Ce-Zr-SBA-15 has been used directly as a catalyst for the synthesis of multi-vall carbon nanotubes (MWCNT) through Chemical Vapor Deposition (CVD). In addition to cerium oxide, it contains zirconium oxide Nano crystallites, which act as catalysts for carbon nanostructures. The catalytic performance of this material was evaluated for the decomposition of ethanol at 900 °C, with N2 flow. The structural characterization of the resulting catalyst was carried out by means of SEM and XRD. The decomposed carbon of absolute ethanol diffuses through the surface of the nanostructured material and precipitates in carbon structures called multiple-walled nanotubes, which could be visualized/detected/identified by TEM, showing diameters of the carbon nanotubes that range from 15 to 25 nm.
Nanoscopic hydrogen reservoir orange peel biowaste
(2022) Juárez, Juliana María; Ledesma, Brenda Cecilia; Anunziata, Oscar A.; Gómez Costa, Marcos Bruno; Beltramone, Andrea Raquel
This work addresses the bio-waste valorization approach for the development of a novel carbonaceous nanomaterial to be used in the adsorption of hydrogen as an alternative in the use of green hydrogen. In this research, activated carbons were synthesized orange peel using different synthesis conditions. With the activated carbons obtained with the best structure and texture, the adsorption of hydrogen and the effects on their meso / microporosity were studied. The activation of the carbon was carried out by means of a chemical process with phosphoric acid as activating agent, varying the acid concentration, the substrate / activating agent ratio, and the contact time between them. The best support was obtained using a carbonization time of 1 h, a carbonization temperature of 470oC, a phosphoric acid concentration of 50% by weight and a BET area of ??1402 m2 / g. Said material significantly improved H2 storage behaviour compared to CMK-3 type nanostructured carbon (3.1% by weight at -196,15 oC and 10 bar). The synthesized material shows promise in absorbing hydrogen by weak binding forces (physisorption).
New method for Ccmk-3 synthesis modified with zr applied in h2 storage
(2021) Juárez, Juliana M.; Gómez Costa, Marcos B.; Venosta, Lisandro F.; Anunziata, Oscar A.
In this work we develop a novel direct synthesis method of modified CMK-3 with zirconium oxide. This modification occurs during the synthesis process. Our assessment includes a one-step synthesis of nanostructured mesoporous carbon modified with zirconium oxide, the characterization of the resulting material by XRD, N2 adsorption, XPS, UV-Vis, TEM, SEM and Raman. We show the enhancement of the storage capacity of the composite material, compared to bare CMK-3.
Novedoso método de síntesis del carbón mesoporoso cmk-3 modificado con circonio y su aplicación en almacenamiento de hidrógeno
(2021) Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.; Venosta, Lisandro F.
En este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno.
Novel omc by nanocasting strategy for hydrogen adsorption
(2021) Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.
A silica material of the SBA-15 type with ultra-large pores (20 nm) was synthesized by the sol-gel method. This silica mesoporous material was impregnated twice consecutively with an acid solution of sucrose and the organic material carbonised inside the mesopores. After dissolution of the silica framework, an ordered mesoporous carbon (OMC) with regular mesopores with mean diameter in the range of 6 nm. The specific surface area of the carbon was increased by increasing filling of the silica pores with the organic material, from 350 m2/g to 950 m2/g. The novel OMC material was successfully synthesized and characterized by X-ray diffraction, textural properties, SEM and transmission electron microscopy analyses. This novel OMC improved significantly the H2 storage behaviour (2.62 wt% at 77 K and 10 bar) compared with a similar CMK-3 (2.18 wt% at 77K and 10 bar). The synthesized material is promising for hydrogen uptake by means of weak bonding (physisorption).
Preparation, characterization and mathematical modeling of keterolac release conteined in lpsba-15 host
(2021) Cussa, Jorgelina; Juárez, Juliana M.; Gómez Costa, Marcos B.; Anunziata, Oscar A.
Drug-controlled release systems can keep the level of drugs in precise doses in the body above the optimal level and with low toxicity. We propose the LP-SBA-15 nanomaterial as a promising new host for drug delivery systems because of its high biocompatibility, in vivo biodegradability, and low toxicity. Ketorolac-LP-SBA-15 was prepared and characterized by XRD, FTIR, UV-Vis DRS, TEM, and texture analysis, determining the adsorption capacity and its release, achieving the required therapeutic efficacy. The host shows ordered mesoporous nanochannels with a diameter of 11-12 nm, maintaining the structure with the incorporation of Keto. The mechanism of drug release the LP-SBA-15 host was evaluated. Different mathematical models were used to adjust the experimental data, being the Ritger-Peppas model followed by the Weibull model the best ones. In this work, we show a promising drug storage material for effective encapsulation and controlled release of KETO, achieving the required therapeutic efficacy. Studies indicate that KETO was adsorbed on the channel surface of LP-SBA-15 without affecting the structure or chemical composition of KETO. Controlled drug delivery systems can achieve precise delivery at the time and place of destination, keeping the concentration of the drug at points in the body within the optimal range and below the toxicity threshold. The study also demonstrates the storage capacity and release properties of LPSBA- 15 containing KETO. The release of KETO contained in LP-SBA-15 can offer a significant improvement in the controlled release of the drug and the analgesic and anti-inflammatory effects, positively influenced, by the links formed between the host and drug molecules and by diffusion through the host porosity. The promising results we obtained for the release of the drug thoroughly using the new material, reaching a rapid initial release rate, and maintaining a constant rate afterward, allow us to maintain the concentration of the drug in the therapeutic efficacy range, applying it largely to the treatment of diseases that require a rapid response.
Síntesis directa del carbón mesoporoso ordenado cmk-3 modificado con circonio aplicado en almacenamiento de energía
(2020) Gómez Costa, Marcos B.; Juárez, Juliana M.; Anunziata, Oscar A.; Venosta, Lisandro F.
En este trabajo, informamos la síntesis y caracterización del material de carbono nanoestructurado (CMK-3) modificado con óxido de circonio sintetizado por una nueva técnica de síntesis directa. Este material es prometedor en la aplicación de adsorción de hidrógeno para el almacenamiento de energía. Los materiales con óxido de circonio (Zr-CMK-3) se sintetizaron con éxito y se caracterizaron por difracción de rayos X, propiedades texturales, UV-Vis-DRS, XPS y análisis de microscopía electrónica de transmisión. El material Zr-CMK-3 mejoró significativamente el comportamiento de almacenamiento de H2 (4,6% en peso a 77 K y 10 bar) en comparación con el soporte CMK-3. El material sintetizado es prometedor en la absorción de hidrógeno por fuerzas de enlace débiles (fisisorción). Se propuso un mecanismo de adsorción de hidrógeno y se discutió el rol de catión Zr+4 en la absorción de hidrógeno.
Sistema de liberación controlada de fármacos: espuma mesoporosa MCF-clorambucilo
(2022) Juárez, Juliana M.; Cussa, Jorgelina; Anunziata, Oscar A.; Gómez Costa, Marcos Bruno
La espuma celular mesoestructurada (MCF) es un material prometedor para los sistemas de administración de fármacos dado a la alta biocompatibilidad, biodegradabilidad y baja toxicidad. Sus propiedades incluyen una gran área superficial, poro grande uniforme. En este trabajo, la espuma mesoporosa MCF fue sintetizada con éxito para su aplicación en nanotransportadores de fármacos, específicamente de Clorambucilo, obteniendo el composite MCF-CBL. La síntesis del material mesoporoso y el proceso de incorporación de Clorambucilo en los poros de la MCF fueron exitosos tal como se muestra en los análisis de XRD, FTIR, TEM y análisis de propiedades texturales. La liberación del fármaco se realizó simulando las condiciones fisiológicas para reproducir las condiciones del organismo. Se evaluó el mecanismo de liberación del fármaco en el hospedaje MCF-CLB. Se utilizaron diferentes modelos matemáticos para ajustar los datos experimentales, el mejor modelo que describe el fenómeno en estudio durante todo el período es el modelo de Weibull. Los resultados auspiciosos que obtuvimos para la liberación del fármaco utilizando el nuevo material, la principal ventaja de esta liberación es que la velocidad de liberación es rápida al inicio y luego disminuye gradualmente hasta que se liberan 24 h prácticamente todo el fármaco contenido en el portador. (> 95%).
Sistema de liberación controlada de fármacos: espuma mesoporosa MCFClorambucilo
(2022) Juárez, Juliana María; Cussa, Jorgelina; Gómez Costa, Marcos Bruno; Anunziata, Oscar A.;
La espuma celular mesoestructurada (MCF) es un material prometedor para los sistemas de administración de fármacos dado a la alta biocompatibilidad, biodegradabilidad y baja toxicidad. Sus propiedades incluyen una gran área superficial, poro grande uniforme. En este trabajo, la espuma mesoporosa MCF fue sintetizada con éxito para su aplicación en nanotransportadores de fármacos, específicamente de Clorambucilo, obteniendo el composite MCFCBL. La síntesis del material mesoporoso y el proceso de incorporación de Clorambucilo en los poros de la MCF fueron exitosos tal como se muestra en los análisis de XRD, FTIR, TEM y análisis de propiedades texturales. La liberación del fármaco se realizó simulando las condiciones fisiológicas para reproducir las condiciones del organismo. Se evaluó el mecanismo de liberación del fármaco en el hospedaje MCFCLB. Se utilizaron diferentes modelos matemáticos para ajustar los datos experimentales, el mejor modelo que describe el fenómeno en estudio durante todo el período es el modelo de Weibull. Los resultados auspiciosos que obtuvimos para la liberación del fármaco utilizando el nuevo material, la principal ventaja de esta liberación es que la velocidad de liberación es rápida al inicio y luego disminuye gradualmente hasta que se liberan 24 h prácticamente todo el fármaco contenido en el portador. (> 95%).
Super-acid sulfated/zirconium-containig nanostructured carbons
(2020) Martínez, María Laura; Anunziata, Oscar A.
In this work, we report the successful preparation of a superacid mesoporous carbon functionalized with sulfated zirconia (SZr-C). SZr-C has a surface area of approximately 1300 m2 g-1, and the total pore volume of 0.94 cm3g-1, composed mainly of mesoporous with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did reveal Zr isolated species. According to the data collected by infrared spectroscopy (FTIR), of pyridine desorbed at various temperatures, the total number of acidic sites was 2.36 mmol/g and the distribution in weak- medium, strong and super acidic sites was determined. The activity in the methylation of aniline indicated that the acid sites are strong, and have not redox properties.
Superacid mesoporous carbón base don sulfated Zr
(2020) Anunziata, Oscar A.; Martínez, María Laura
In this brief communication we report the successful preparation of a promising material with acidic properties from starch-derived mesoporous carbon (SMC), functionalized with sulfated zirconia. The process of assembling P123, starch, zirconia and silicon produces ordered mesoporous carbon modified with Zr. Reaction time and temperature are essential to avoid the appearance of poorly assembled or unsightly structures, reducing the surface area and the size of the pores. Zr-SMC has a surface area of approximately 1300 m2 g-1, and the total pore volume of 0.94 cm3 g-1, composed mainly of mesopores with an average pore size of 3.5 nm. The composition of the surface and the chemical states of the elements did not reveal ZrO2 as isolated clusters. Through the thermodesorption of the pre-adsorbed ammonia in the sulfated Zr-SMC, the total ammonia retained is 1.80 mmol / g at high temperature, exhibiting medium to strong acidity.
Superacid sulfated-zirconia mesoporous carbon (szrmc) “efficient chemotherapeutic agent”.
(2021) Anunziata, Oscar A.
The goal of this work is the incorporation of zirco-nium, in the process of self-assembly of the tem-plate agents (P123) and hydrolyzed TEOS, and a source of carbon in the original synthesis mixture. This direct incorporation of zirconia leads, after carbonization, to ordered mesoporous carbon mate-rial, with zirconium in its structure (SZr-MC), and without zirconium oxide as a bulky species. The sulfated mesoporous carbon has a high acidity that can make the SZr-MC nanoscopic material, with super acidic properties. We have designed a novel synthesis procedure for the formation of acidic mesoporous carbon-based nanomaterials function-alized with sulfated zirconia. During the crystalliza-tion process, P123, A-type starch, zirconia and sili-con were able to cohesionize. After sulphuric treat-ments, the physical characteristics of the parent car-bon were retained in the ultimate material, reveal-ing a great surface area (1300 m2/g), a large pore volume and a well-ordered porosity composed of uniform mesopores of approximately 3.5 nm. XRD, SEM, TEM and XPS studies indicated the absence of ZrO2 as a bulk species. Therefore, Zr as an iso-lated species was successfully anchored in the MC for subsequent sulfation. Furthermore, evidence from the XPS C 1s data can be attributed to the sp2 hybridized carbon (from the graphitic structure of the mesoporous carbon), which would form Zr-C bonds. In addition, the large amount of -OH groups, coming from the starch used as carbon source, would promote the formation of Zr-O-C species (also detected by XPS), forming part of the MC walls, in the self-assembly process.The evidence of two high temperature desorption peaks in the NH3-TPD profile and the high pyridine retention temper-ature determined by FTIR revealed medium, strong and super-strong acid sites in the SZrMC, and it can be assumed that these sites correspond to a su-peracid nanomaterial.
Synthesis and characteristics of magnetite containing-cmk-3 and its application in hydrogen storage
(2020) Juárez, Juliana M.; Venosta, Lisandro F.; Gómez Costa, Marcos B.; Anunziata, Oscar A.
In this work, we report the synthesis and characterization of iron oxide nanoparticles (Magnetite) supported on CMK-3. The materials were characterized by XRD, SEM, TEM, XPS and magnetization studies. A large amount of the iron incorporated as iron oxide nanoparticles was in the magnetite phase. The incorporation of magnetite on the CMK-3 carbon surface significantly improved the hydrogen storage capacity (4.45 wt. % at 77 K and 10 bar) compared to the CMK-3 structure (2.20 wt% at 77 K and 10 bar). Magnetite nanoparticles play a key role in H2 adsorption.

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