Gotowe bibliografie tematyczne / Co2P Nanoparticles

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Gotowa bibliografia na temat „Co2P Nanoparticles”

Autor: Grafiati

Data publikacji: 6 września 2023

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Artykuły w czasopismach na temat "Co2P Nanoparticles"

Green, Michael, Lihong Tian, Peng Xiang, James Murowchick, Xinyu Tan i Xiaobo Chen. "Co2P nanoparticles for microwave absorption". Materials Today Nano 1 (marzec 2018): 1–7. http://dx.doi.org/10.1016/j.mtnano.2018.04.004.

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Sun, Xingwei, Haiou Liang, Haiyan Yu, Jie Bai i Chunping Li. "Embedding Co₂P nanoparticles in Cu doping carbon fibers for Zn–air batteries and supercapacitors". Nanotechnology 33, nr 13 (7.01.2022): 135202. http://dx.doi.org/10.1088/1361-6528/ac43ea.

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Abstract Developing highly efficient and non-precious materials for Zn–air batteries (ZABs) and supercapacitors (SCs) are still crucial and challenging. Herein, electronic reconfiguration and introducing conductive carbon-based materials are simultaneously conducted to enhance the ZABs and SCs performance of Co2P. We develop a simple and efficient electrospinning technology followed by carbonization process to synthesize embedding Co2P nanoparticles in Cu doping carbon nanofibers (Cu-Co2P/CNFs). As a result, the 7% Cu-Co2P/CNFs presents high oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) activity (half-wave potential of 0.792 V for ORR, an overpotential of 360 mV for OER). The ZABs exhibit a power density of 230 mW cm−2 and excellent discharge-charge stability of 80 h. In addition, the 7% Cu-Co2P/CNFs show the specific capacitance of 558 F g−1 at 1 A g−1. Moreover, the 7% Cu-Co2P/CNFs//CNFs asymmetric supercapacitor was assembled applying 7% Cu-Co2P/CNFs electrode and pure CNFs, which exhibits a high energy density (25.9 Wh kg−1), exceptional power density (217.5 kW kg−1) and excellent cycle stability (96.6% retention after 10 000 cycles). This work may provide an effective way to prepared Co2P based materials for ZABs and SCs applications.

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Wang, Ke, Ruimin Zhang, Yun Guo, Yunjie Liu, Yu Tian, Xiaojun Wang, Peng Wang i Zhiming Liu. "One-Step Construction of Co2P Nanoparticles Encapsulated into N-Doped Porous Carbon Sheets for Efficient Oxygen Evolution Reaction". Energies 16, nr 1 (1.01.2023): 478. http://dx.doi.org/10.3390/en16010478.

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It is critical and challenging to develop high performance transition metal phosphides (TMPs) electrocatalysts for oxygen evolution reaction (OER) to address fossil energy shortages. Herein, we report the synthesis of Co2P embedded in N-doped porous carbon (Co2P@N-C) via a facile one-step strategy. The obtained catalyst exhibits a lower overpotential of 352 mV for OER at a current density of 10 mA cm−2 and a small Tafel slope of 84.6 mV dec−1, with long-time reliable stability. The excellent electrocatalytic performance of Co2P@N-C can be mainly owed to the synergistic effect between the Co2P and highly conductive N-C substrate, which not only affords rich exposed active sites but also promotes faster charge transfer, thus significantly promoting OER process. This work presents a promising and industrially applicable synthetic strategy for the rational design of high performance nonnoble metal electrocatalysts with enhanced OER performance.

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Shi, Qing, Yapeng Zheng, Weijun Li, Bin Tang, Lin Qin, Weiyou Yang i Qiao Liu. "A rationally designed bifunctional oxygen electrocatalyst based on Co2P nanoparticles for Zn–air batteries". Catalysis Science & Technology 10, nr 15 (2020): 5060–68. http://dx.doi.org/10.1039/d0cy01012j.

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A highly-efficient Co₂P-based bifunctional oxygen catalyst has been developed though an enhanced coupling with N,P co-doped carbon nanoparticles and 3D carbon networks, which exhibits better bi-catalytic performance than benchmark noble metal-based counterparts.

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Zhang, Xiaofang, Aixian Shan, Sibin Duan, Haofei Zhao, Rongming Wang i Woon-Ming Lau. "Au@Co2P core/shell nanoparticles as a nano-electrocatalyst for enhancing the oxygen evolution reaction". RSC Advances 9, nr 70 (2019): 40811–18. http://dx.doi.org/10.1039/c9ra07535f.

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Jebaslinhepzybai, Balasingh Thangadurai, Thamodaran Partheeban, Deepak S. Gavali, Ranjit Thapa i Manickam Sasidharan. "One-pot solvothermal synthesis of Co2P nanoparticles: An efficient HER and OER electrocatalysts". International Journal of Hydrogen Energy 46, nr 42 (czerwiec 2021): 21924–38. http://dx.doi.org/10.1016/j.ijhydene.2021.04.022.

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Das, Debanjan, Debasish Sarkar, Sudhan Nagarajan i David Mitlin. "Cobalt phosphide (Co2P) encapsulated in nitrogen-rich hollow carbon nanocages with fast rate potassium ion storage". Chemical Communications 56, nr 94 (2020): 14889–92. http://dx.doi.org/10.1039/d0cc07123d.

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Stelmakova, M., M. Streckova, R. Orinakova, A. Guboova, M. Balaz, V. Girman, E. Mudra, C. Bera i M. Batkova. "Effect of heat treatment on the morphology of carbon fibers doped with Co2p nanoparticles". Chemical Papers 76, nr 2 (7.10.2021): 855–67. http://dx.doi.org/10.1007/s11696-021-01897-0.

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Zhang, Dan, Panpan Sun, Zhuang Zuo, Tao Gong, Niu Huang, Xiaowei Lv, Ye Sun i Xiaohua Sun. "N, P-co doped carbon nanotubes coupled with Co2P nanoparticles as bifunctional oxygen electrocatalyst". Journal of Electroanalytical Chemistry 871 (sierpień 2020): 114327. http://dx.doi.org/10.1016/j.jelechem.2020.114327.

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Diao, Lechen, Tao Yang, Biao Chen, Biao Zhang, Naiqin Zhao, Chunsheng Shi, Enzuo Liu, Liying Ma i Chunnian He. "Electronic reconfiguration of Co2P induced by Cu doping enhancing oxygen reduction reaction activity in zinc–air batteries". Journal of Materials Chemistry A 7, nr 37 (2019): 21232–43. http://dx.doi.org/10.1039/c9ta07652b.

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Rozprawy doktorskie na temat "Co2P Nanoparticles"

Fu, Chunkai. "Investigation of the Stability of Nanoparticles under Different Conditions and Rheology of Nanoparticle-Stabilized CO2 Foam". Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10814705.

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A high-pressure CO2 foam was generated with silica nanoparticle dispersion and CO2 for fracturing applications. The effects of different ions and temperature on nanoparticle aggregation were studied. Nanoparticle dispersions were mixed with individual monovalent, divalent ions with varying concentrations, and two synthesized Permian connate water solutions. Samples of nanoparticle dispersions with the presence of NaCl were put into chambers with constant temperature for 14 hours. The peak size of aggregated nanoparticles in each sample was measured. It was found this silica nanoparticle dispersion had a high thermal stability up to 85?. The silica nanoparticle dispersion used in this study maintained a desired stability under an 18% reservoir salinity condition, yet it could be sensitive to high concentrations of Na2SO4 solutions. To investigate foam rheology and stability, high-pressure CO2 foams were generated in a beadpack with different CO2/NP ratios in NaCl solutions. The resulting foam was observed in a sapphire tube. The differential pressure across a capillary tube was recorded to calculate the apparent viscosity of foams. Nanoparticle-stabilized foams could remain stable for days and foam stability decreased with the increasing foam quality. Foam apparent viscosity was found to increase with foam quality and could be 3 times as high as that of the ambient phase. The high stability and fine texture of high-pressure CO2-in-water foams stabilized by silica nanoparticles have broadened the development of foam fracturing, offering a new opportunity for the effective development and stimulation of unconventional reservoirs.

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Garg, Garima. "Solvants ioniques biosourcés et CO2 supercritique : conception des processus durables pour la synthèse de molécules cibles (BISCO2)". Thesis, Toulouse, INPT, 2019. http://www.theses.fr/2019INPT0085.

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Cette thèse représente un projet multidisciplinaire qui explore des aspects allant de l'ingénierie des solvants à la catalyse à l'aide de nanoparticules métalliques. Dans le cadre de ce projet, l’ingénierie des solvants a été appliquée à des solvants eutectiques profonds (SEP) biosourcés synthétisés à partir de tosylalaninate de choline et de glycérol afin diminuer leur viscosité en utilisant différentes quantités de dioxyde de carbone. Les rotors moléculaires ont été utilisés comme méthode innovante pour mesurer la viscosité, évitant ainsi l’utilisation d’une instrumentation coûteuse et donnant accès à la microviscosité du système. De plus, ce système a été appliqué à la synthèse de nanoparticules de palladium, jouant également un rôle de stabilisants, qui ont été entièrement caractérisées. Les nanoparticules de palladium bien dispersées ont été ensuite utilisées pour l'hydrogénation catalytique de liaisons C-C insaturées, de groupes nitro et carbonyle. Le CO2 dans ses états sub- ou supercritique a été utilisé pour améliorer l'efficacité des nanoparticules de palladium dans les réactions d'hydrogénation catalytique et subséquemment pour l'extraction du produit après la réaction de catalyse. Ce travail représente an effort pour intensifier un procédé dehydrogénation dans un milieu très visqueux, non volatile, biodégradable, biosourcé et non-toxique en utilisant du CO2 1) pour améliorer le transfert de matière et 2) pour extraire les produits de la réaction du milieu réactionnel
This Thesis represents a multi-disciplinary project where aspects going from solvent engineering to catalysis using metal-based nanoparticles, are explored. In this project, solvent engineering has been applied to bio-based deep eutectic solvents (DES) synthesized from choline tosylalaninate and glycerol in an effort to decrease the solvent viscosity by using different amounts of carbon dioxide. In this context, molecular rotors were used as an innovative method to measure the viscosity, avoiding the use of expensive instrumentation and giving the possibility to access to the microviscosity of the system. Furthermore, DES have been applied for the synthesis of palladium nanoparticles, also acting as stabilizers, which were fully characterized. The as-prepared palladium nanoparticles were then used for catalytic hydrogenations of unsaturated C-C bonds, and nitro and carbonyl groups. Sub and supercritical CO2 conditions have been applied to improve the efficiency of the palladium nanocatalysts in hydrogenation reactions and afterwards for the extraction of organic products. This work represents an effort to intensify a hydrogenation process in a highly viscous, non-volatile, biodegradable, and non-toxic DES by using CO2 in order to decrease mass transfer limitations and to extract products from the reaction media

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LIENDO, CASTILLO FREDDY JESUS. "CO2 conversion through the synthesis of CaCO3 nanoparticles". Doctoral thesis, Politecnico di Torino, 2021. http://hdl.handle.net/11583/2907014.

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Benzaqui, Marvin. "Synthesis of Metal-Organic Framework nanoparticles and mixed-matrix membrane preparation for gas separation and CO2 capture". Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLV075/document.

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La séparation CO2/N2 et H2/CO2 permet de limiter le rejet de CO2 dans l’atmosphère issu des gaz industriels et les membranes présentent de nombreux avantages tant sur le plan économique que pratique. Les membranes polymère sont faciles à mettre en forme mais un compromis entre perméabilité et sélectivité doit généralement être trouvé : pour améliorer les performances, des membranes à matrice mixte (MMM) incorporant des MOFs (matériaux hybrides poreux cristallisés) dispersés dans la phase polymère ont été proposées. A la différence des matériaux poreux inorganiques, les MOFs ont une meilleure compatibilité avec la matrice polymère du fait de leur caractère hybride organiqueinorganique. Dans le cadre de cette thèse, des polycarboxylates de Fe3+ et Al3+ poreux, stables à l’eau, et possédant de bonnes propriétés d’adsorption sélective du CO2 ont été synthétisés en milieu aqueux et mis à l’échelle de quelques grammes. Deux nouveaux polycarboxylates de Fe3+ poreux fonctionnalisés par des fonctions -COOH libres ont été obtenus à température ambiante. Pour l’un d’entre eux, la structure a été déterminée par diffraction des rayons X. Une deuxième partie de la thèse a été consacrée à la synthèse de nanoparticules de MOFs avec un bon rendement. Une partie importante de ce travail a porté sur le contrôle de la taille et la morphologie des nanoparticules de MIL-96(Al). Ce travail a conduit à la préparation de MMMs à base de MIL-96(Al) dont les performances sont supérieures à la membrane pure polymère pour la séparation CO2/N2. La dernière partie de ce travail de thèse a porté sur l’étude physico-chimique de la compatibilité entre le ZIF-8 et deux polymères (PVA et PIM-1). Ce travail a consisté à effectuer une caractérisation complète de solutions colloïdales MOFs/polymère en couplant plusieurs techniques (DLS, TEM, SAXS). Cette étude a montré que la compatibilité MOF/polymère est très dépendante de la chimie de surface des MOFs et des propriétés physico-chimiques du polymère (rigidité, caractère hydrophile/hydrophobe…)
CO2 capture and storage (CCS) is of high economical and societal interest. CO2/N2 andH2/CO2 separations are able to limit atmospheric CO2 emissions produced by industrial exhausts andmembranes present numerous economical and practical advantages. Polymer membranes are easy toprocess and possess interesting mechanical properties. However, there is a trade-off to make betweenpermeability and selectivity. Mixed-matrix membranes (MMM) based on MOFs (porous crystallinehybrid materials) have been proposed to boost the performances of polymer membranes for CO2capture. In comparison to other inorganic porous materials, one may expect that the compatibilitybetween MOFs and polymers is enhanced due to the hybrid character of MOFs.In this work, porous water stable polycarboxylate MOFs based on Fe3+ and Al3+ with promisingproperties for CO2 adsorption were synthesized for large-scale production using water as the mainsolvent. Two new porous polycarboxylate Fe3+ MOF bearing free -COOH groups in the frameworkwere obtained at room temperature as nanoparticles. The crystallographic structure of one of thesematerials was determined by single crystal X-ray diffraction. A second part of the thesis was devotedto the synthesis of MOFs nanoparticles with good yield. We focused our attention on the control of thediameter and morphology of MIL-96(Al) nanoparticles. This study led to the preparation of MMMsbased on MIL-96(Al) with promising properties for CO2/N2 separation. Finally, the compatibilitybetween MOF particles and polymers was studied for two systems (ZIF-8/PIM-1 and ZIF-8/PVOH),showing the influence of the surface chemistry of MOFs and the physico-chemical properties ofpolymer on the matching between MOFs and polymers

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Kim, Ara. "Nanostructured Ru/TiO2 catalysts for CO2 methanation". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066067.

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L’hydrogénation du CO2 par voie catalytique hétérogène représente une stratégie pertinente pour atténuer les émissions. Cette thèse a pour but de contribuer à la compréhension des facteurs physico-chimiques qui déterminent l’activité de catalyseurs Ru/TiO2 en conditions douces (= 200 °C, 1 atm). Des nanoparticules de RuO2 de 2 nm sont utilisées comme précurseurs de la phase active de Ru métallique. Ces nanoparticules calibrées sont combinées avec plusieurs supports de TiO2 présentant diverses cristallinités, textures, stabilité et compositions, dans le but de comprendre les paramètres qui dictent l’activité des catalyseurs Ru/TiO2. Les interactions spécifiques entre le support de TiO2 et les nanoparticules de RuO2 sont mises en évidence via différentes techniques avancées incluant la tomographie et la microscopie électronique en transmission environnementale à pression atmosphérique. Il apparait que le paramètre clé conférant une activité catalytique élevée est la stabilisation épitaxiale de RuO2 sur le TiO2 rutile lors de l’étape d’activation qui précède la réduction vers la forme Ru métallique
The hydrogenation of CO2 performed through heterogeneous catalysis is a pertinent strategy for mitigating CO2 emissions. This thesis aims to contribute to the understanding of the physico-chemical factors related to the catalytic performance of Ru/TiO2 catalysts at mild conditions (= 200 °C, 1 atm). Pre-synthesized 2 nm-RuO2 nanoparticles (NPs) are used to serve as precursors for active metallic Ru. These calibrated NPs are coupled with various tailor made TiO2 supports with different crystallinity, textural properties, stability and composition to understand parameters that dictate the activity of Ru/TiO2 catalysts. The specific RuO2-TiO2 interactions and RuO2 NPs migration phenomenon are demonstrated using various techniques including the state-of-the-art tomography and environmental transmission electron microscopy at atmospheric pressure. The important parameter for the better catalytic performance is found to be the epitaxial stabilization of RuO2 on rutile TiO2 prior to the formation of active Ru phase

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Hijazi, Nibal. "Développement de composites nanostructurés à base de biopolyesters et de nanoparticules de chitosane générées par des procédés assistés par CO2 supercritique". Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2014. http://www.theses.fr/2014EMAC0016/document.

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Dans une logique d’éco-conception et de développement durable, de nombreux travaux ont pour objectif l’étude de polymères biosourcés. Parmi les recherches menées à ce jour, une piste d’étude consiste à les structurer aux échelles micro et nanoscopiques tout en valorisant certaines de leurs propriétés spécifiques, l’objectif étant la création de matériaux à propriétés fonctionnelles originales et performantes. Dans ce contexte, une attention particulière a été portée sur l’utilisation du dioxyde de carbone supercritique (CO2-sc). En effet, sa capacité à se solubiliser en grande quantité dans de nombreux polymères et donc d’en modifier les propriétés (viscosité, tension interfaciale, …) peut permettre une amélioration des matériaux composites fabriqués. Ce projet s’intéresse plus particulièrement à l’élaboration d’assemblages de biopolymères nanostructurés et revêt deux enjeux principaux : (1) la synthèse de nanoparticules de biopolymères (dans notre cas, du chitosane), (2) l’élaboration d’assemblages de biopolymères nanostructurés. La première étape a consisté à concevoir et développer de nouveaux procédés de génération de nanoparticules de chitosane par des procédés utilisant le CO2-sc soit comme antisolvant soit comme agent de dissolution et d'atomisation. Pour la deuxième étape, des films composites à base de poly (acide lactique) PLA et de poly (hydroxybutyrate-co-valérate) PHBV ont été préparés par la voie hot-melt par extrusion bi-vis. Des analyses thermiques, moléculaires et structurales, morphologiques et de granulométrie ont permis de caractériser les films biocomposites ainsi produits
In a logic of eco-design and sustainable development, many works aim to study the bio-sourced polymers. Among these studies, a promising concept consists in structuring materials at micro and nanoscales while enhancing some of their properties, the objective being the creation of original materials with improved functional properties and performance. In this context, particular attention has been paid to the use of supercritical carbon dioxide (sc-CO2). Its ability to dissolve into many polymers in large quantities and thus to change their properties (viscosity, interfacial tension, ...), can improve both the composite material and its manufacturing process. This project focuses on the development of nanostructured biopolymers and addresses two main issues: (1) the synthesis of biopolymer nanoparticles (in this case, chitosan), and (2) the development of nanostructured biopolymers. The first step consisted in designing and developing new processing methods to generate biopolymer nanoparticles, using sc-CO2 as antisolvent agent or as dissolving and atomizing agent. For the second step, poly (lactic acid) PLA and poly (hydroxybutyric-co-hydroxyvaleric acid) PHBV based composite films were prepared by a hot-melt process by twin-screw extrusion of the nanoparticles and the matrix. Thermal, molecular and structural analysis, as well as morphological and particle size distribution studies allowed a good characterization of the biocomposite films

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Kaydouh, Marie-Nour. "Confinement effect of Nickel in mesoporous silica-based catalysts for syngas production by reforming of methane with CO2". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066425/document.

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Malgré ses avantages économiques et environnementaux, le procédé de reformage à sec du méthane sur des catalyseurs au nickel supporté se heurte encore à des problèmes de frittage de la phase active (un métal de transition) et de dépôt de carbone, ce qui entraîne une diminution de l'activité catalytique. Cette thèse porte sur l'étude de l'effet de confinement du nickel dans des catalyseurs à base de silice mésoporeuse pour la production de gaz de synthèse par reformage du méthane par le CO2. Dans cette étude, les échantillons ont été caractérisés par physisorption de N2, DRX, MET/MEB, RTP, et, en plus, par Raman, SPX, HTP/SM, ATG/SM pour les catalyseurs après test catalytique. Les résultats montrent qu'un support mésoporeux bien structuré ayant une grande surface spécifique et un grand volume poreux est important pour une meilleure dispersion et stabilisation de la phase active à l'intérieur de la porosité. La silice mésoporeuse de SBA-15 (préparée en grande quantité), composée de grains allongés, semble être appropriée pour atteindre cet objectif. Il est de plus démontré que la formation de petites particules bien confinées à l'intérieur des pores favorise la résistance au dépôt de carbone. Ceci peut être obtenu en imposant un traitement hydrothermal au support, en utilisant la méthode deux solvants pour le dépôt de Ni, en passant à une réduction directe des échantillons non calcinés, en ajoutant du Rh en faibles quantités ou en utilisant du Ce comme promoteur, à condition que le Ni et Ce soient en interaction
Although economically and environmentally advantageous, the methane dry reforming process using supported nickel based catalysts still faces problems of active phase (a transition metal) sintering and of carbon deposition, which result in catalytic activity loss. This thesis is focused on the study of the confinement effect of nickel in mesoporous silica-based catalysts for syngas production by reforming of methane with CO2. In this study, the samples were characterized by N2 sorption, XRD, TEM/SEM, TPR, in addition to Raman, XPS, TPH/MS, TGA/MS for the spent catalysts. The results indicate that a well-structured mesoporous support with high surface area and large pore volume is important for better dispersion and stabilization of the active phase inside the porosity. The mesoporous SBA-15 silica support (prepared in large quantity), composed of elongated grains, appear to be suitable for the purpose. Moreover, it is demonstrated that the formation of small nickel particles well-confined inside the pores favors carbon resistance. This can be achieved by applying hydrothermal treatment to the support, using two solvents method for Ni deposition, using direct reduction of uncalcined samples, adding Rh in small quantities or promoting with Ce, provided that Ni and Ce are in interaction

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De, Masi Deborah. "Nanoparticules bimétalliques combinant propriétés catalytiques et physiques pour la valorisation du CO2 et de la biomasse". Thesis, Toulouse, INSA, 2019. http://www.theses.fr/2019ISAT0024.

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Les réactions réalisées en catalyse hétérogène nécessitent des températures et pressions élevées. Une façon originale pour améliorer ces conditions de réaction est de générer des températures élevées directement à la surface des catalyseurs par des stimuli physiques (magnétiques ou plasmoniques). L’objectif de cette thèse a été la mise en place de la synthèse de nanoparticules complexes combinant des propriétés physiques et des propriétés catalytiques. Ainsi, deux types de nanoparticules ont été synthétisées, des nanoparticules de fer-nickel pour le chauffage magnétique et des nanoparticules bimétalliques or-ruthénium pour le chauffage plasmonique. Dans le contexte actuel de développement durable et de stockage des énergies renouvelables, nous avons étudié deux réactions catalytiques : la réaction de Sabatier et l’hydrodésoxygénation de molécules plateformes issues de la biomasse lignocellulosique. Sous champ magnétique, la génération au voisinage des nanoparticules de fer-nickel de très hautes températures a permis de créer un environnement hétérogène à la surface des nanoparticules. Ainsi, la conversion totale du furfural et de l’hydroxyméthylfurfural en biocarburants (le méthylfurane et le diméthylfurane) a pu être réalisée en solution dans des conditions très douces. Les propriétés de chauffe et les propriétés catalytiques des nanoparticules de fer-nickel ont permis d’activer la réaction de Sabatier, et d’atteindre pour la première fois des rendements en méthane de 100 %. Dans la même optique, les propriétés plasmoniques et catalytiques des nanoparticules d’or-ruthénium ont été étudiées pour la réaction de Sabatier. Un couplage entre chauffage classique et irradiation lumineuse a permis de mettre en évidence un effet synergique entre le ruthénium et l’or pour l’activation de la réaction
Heterogeneous catalytic reactions require often very harsh conditions, i.e. high temperature and high pressure in the overall system. An original way to lower these reaction conditions consists in generating a local heating directly at the surface of the catalysts by the means of physical stimuli (magnetic or plasmonics). However, up to now, the catalytic sites and the heating agents were spatially separated, reducing the efficiency of the heat transfer. The aim of this thesis is thus to elaborate complex bimetallic nanoparticles combining physical properties and catalytic properties in the very same object. Two types of nanoparticles have been synthesized, iron-nickel nanoparticles for magnetic heating and gold-ruthenium nanoparticles for plasmonic heating. In the current context of sustainable development and storage of renewable energies, we studied two catalytic reactions: the Sabatier reaction, to valorize CO2 gas and the hydrodeoxygenation of platforms molecules from lignocellulosic biomass to yield biofuel. Under alternating magnetic field, iron-nickel nanoparticles generate high temperatures creating a heterogeneous environment at their surface. Thanks to these peculiar conditions, the furfural and the hydroxymethylfurfural could be totally converted, in liquid phase, into biofuels (methylfurane and dimethylfurane) under mild conditions. Moreover, heat properties of iron-nickel nanoparticles combining with their catalytic properties have made possible the total conversion of carbon dioxide into methane. Similarly, plasmonic and catalytic properties of gold-ruthenium nanoparticles were studied for the Sabatier reaction. By coupling classical heating and light irradiation a synergetic effect between ruthenium and gold was observed leading to the efficient activation of the reaction

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Ali, Muhammad. "Effect of Organics and Nanoparticles on CO2-Wettability of Reservoir Rock; Implications for CO2 Geo-Storage". Thesis, Curtin University, 2021. http://hdl.handle.net/20.500.11937/83829.

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In this study, we have investigated the effect of various organic acids (hexanoic, lauric, stearic, and lignoceric acid) and nanoparticles (silica and alumina) on various geo-storage formations (sandstone, carbonate, and cap-rock) by conducting contact angle measurements at various physio-thermal conditions. The result showed that geo-storage minerals became super-hydrophobic in the presence of organic acids, thus, less CO2 trapping capacity and nano-fluids have significantly turned organic-aged geo-storage minerals to intermediate-wet, thus, increased CO2 trapping capacity.

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Gu, Yingying. "Membranes polymères fonctionnalisées par des poly(liquide ionique)s et des nanoparticules de palladium : applications au captage de CO2 et aux membranes catalytiques". Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30157/document.

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Des membranes supports en polymère ont été photo-greffées par des poly(liquide ionique)s (polyLIs) à base d'imidazolium. Les polyLIs permettent de séparer le CO2 d'autres gaz et de stabiliser des nanoparticules. Dans le cas du captage de CO2, les expériences montrent qu'une couche fine homogène de gel réticulé en polyLI gonflé par du liquid ionique (LI) est obtenue sur la surface de fibres creuses. Les fibres ainsi obtenues ont montré des perméances au CO2 plus élevées (600-700 GPU) que des membranes commerciales et des sélectivités de CO2/N2 comparables (13 et 17). Dans le cas de membranes catalytiques, des nanoparticules de palladium (NPPd) servant de catalyseur ont été immobilisées en forte concentration locale au sein d'une couche de polyLI greffée à la surface de membranes. La réactivité des membranes catalytiques a été testée en configuration de contacteur traversé sur différentes réactions (couplage croisé C-C, hydrogénation, etc). Une conversion totale est obtenue pour des temps de séjours de quelques secondes, sans aucun sous-produit formé. Comparée aux NPPd colloïdaux dans un réacteur en batch, la membrane catalytique accélère les réactions d'environ 2000 fois en terme de temps de réaction sans perte de NPPd; la sélectivité est aussi accrue. Le réacteur membranaire catalytique a été modélisé afin d'obtenir les profils de concentration et de température et une meilleure compréhension des performances obtenues. Les membranes catalytiques se révèlent isothermes et les constantes cinétiques sont calculées. Enfin, les capacités de production de ces membranes catalytiques à une échelle industrielle sont estimées à environ 3 t/(hm3) pour le couplage de Suzuki
Polymeric support membranes were modified via photo-grafting by poly(ionic liquid)s (polyILs), featuring in the capability to separate CO2 from other gases and to stabilize metallic nanoparticles (MNPs). For CO2 capture, a thin polyIL-IL gel layer was homogenously coated on support hollow fibers. The composite fibers show high CO2 permeance and reasonable CO2/N2 selectivity. For the catalytic membrane, palladium NPs were generated inside a grafted polyLI layer. Compared to colloidal palladium system in a batch reactor, the catalytic membrane, as a contactor membrane reactor, is more efficient in terms of reaction time (ca. 2000 times faster), selectivity and MNP retainability. Theoretical study on reactor modeling, concentration & temperature profiles, and production capacity was done for an overall understanding of the catalytic membrane

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Części książek na temat "Co2P Nanoparticles"

Guo, Feng, i Saman A. Aryana. "Nanoparticle-Stabilized CO2 Foam Flooding". W Advances in Petroleum Engineering and Petroleum Geochemistry, 61–63. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-01578-7_15.

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Yu, W., T. Wang, M. X. Fang, H. Hei i Z. Y. Luo. "CO2 Absorption/Desorption Enhanced by Nanoparticles in Post-combustion CO2 Capture". W Clean Coal Technology and Sustainable Development, 591–96. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-10-2023-0_80.

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Kumar, Santosh, Wei Li i Adam F. Lee. "Chapter 8. Nanocatalysts for CO2 Conversion". W Nanoparticle Design and Characterization for Catalytic Applications in Sustainable Chemistry, 207–35. Cambridge: Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788016292-00207.

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Sagar, Vikram Tatiparthi, i Albin Pintar. "Supported Metal Nanoparticles and Single-Atoms for Catalytic CO2 Utilization". W ACS Symposium Series, 241–66. Washington, DC: American Chemical Society, 2020. http://dx.doi.org/10.1021/bk-2020-1360.ch010.

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Yang, Guoxiang, Yasutata Kuwahara, Kohsuke Mori i Hiromi Yamashita. "Hollow Carbon Spheres Encapsulating Metal Nanoparticles for CO2 Hydrogenation Reactions". W Core-Shell and Yolk-Shell Nanocatalysts, 425–40. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0463-8_26.

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Sato, Tsugio, Chong-shen Guo i Shu Yin. "Novel Tungsten Bronze Nanoparticles for Shielding Near Infrared Ray and Decreasing CO2 Emission". W Energy, Transportation and Global Warming, 349–54. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30127-3_27.

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Li, Weiqin, Zaiping Nie i Wenhe Xia. "CO2 Sequestration Electromagnetic Imaging Based on Nanoparticle Contrast Agent and Casing Excitation". W Proceedings of the International Field Exploration and Development Conference 2018, 705–12. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-7127-1_65.

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Yanchi, Jiang, Zhang Zhongxiao, Yu Juan, Zhao Ziqi, Fan Junjie, Li Boyang, Jia Mengchuan i Mu Aiwei. "Comprehensive Analyses on Activation Agents of Amines and Nanoparticles for TETA-Based CO2 Capture Absorbents". W Clean Coal and Sustainable Energy, 607–20. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-1657-0_47.

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Kashetti, Shrutika, Greeshma K. Anand i Priya C. Sande. "CFD Simulation of EOR Technique, by Gas Injection of CO2-LPG Along with the Nanoparticles by Using the Eulerian–Eulerian Approach". W Lecture Notes in Mechanical Engineering, 237–48. Singapore: Springer Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-6928-6_20.

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Natividad, Reyna. "CO2 photoconversion catalyzed by nanoparticles supported on TiO2". W Nanoparticles in Green Organic Synthesis, 421–52. Elsevier, 2023. http://dx.doi.org/10.1016/b978-0-323-95921-6.00013-5.

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Streszczenia konferencji na temat "Co2P Nanoparticles"

Li, Lirong, i Yong Tae Kang. "Three-Dimensional Simulation of Bubble Behavior and Mass Transfer for CO2 Absorption in Nanoabsorbents". W ASME 2019 6th International Conference on Micro/Nanoscale Heat and Mass Transfer. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/mnhmt2019-3944.

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Abstract CO2 absorption performance in gas-liquid system is affected by nanoparticles. The enhancement mechanisms involved have been extensively paid attention. The CO2 gas bubble behaviors and the characteristics of the nanoparticle motion have been clarified in the present study. The equivalent substitution method is used to regard the liquid with nanoparticles as a continuous term with changed physical properties, that is, nanofluid. Therefore, the volume-of-fluid (VOF) method is employed to well predict the gas bubble behaviors and mass transfer coefficient in nanofluid. It is found that the mass transfer coefficient in the gas-liquid system for CO2 absorption can be significantly enhanced by Al2O3 nanoparticles. With the increase of nanoparticles volume concentration, the surface renewal frequency increases dramatically. The discrete-particle-method (DPM) is adopted to track the motion of nanoparticles. In this way, the deformation of the bubbles and the motion of the nanoparticle are well captured. It is concluded that the enhanced mass transfer coefficient in gas-liquid-nanoparticle system is not only related to the Brownian motion of the particles, but also related to the nanoparticle deduced turbulence in the liquid field.

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Alfakher, Ahmad M., i David A. DiCarlo. "Reduced Carbon Dioxide Mobility in Experimental Core Flood Using Surface Coated Silica Nanoparticles as a Foaming Agent". W Offshore Technology Conference. OTC, 2023. http://dx.doi.org/10.4043/32382-ms.

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Abstract Carbon dioxide (CO2) is the most used solvent in enhanced oil recovery (EOR), as it can have a high displacement efficiency in favorable conditions. Its disadvantages are relatively low sweep efficiencies caused by a viscosity and density that is lower than the fluid it displaces. Surface-coated silica nanoparticles create in-situ CO2 foam, which has a more favorable mobility ratio and therefore better sweep. These nanoparticles can also be used in carbon capture and storage (CCS) applications in injecting CO2 foam into brine aquifers. This paper presents the results of core flood experiments that aimed to study surface coated silica nanoparticles as an in-situ CO2 foaming agent. In these experiments, pressure drop was measured across the core as a whole and in five individual sections. The core was placed vertically, and liquid CO2 was pumped at the top of the core. Surface coated silica nanoparticles suspended in the brine is used in some of the floods and compared to a control flood that had no nanoparticles. In these experiments, pressure drops in nanoparticle cases were a multiple of 5-10 those in the control cases. In addition, total core pressure drops in nanoparticle cases increased as the core got more saturated with CO2, and the increase was observed sequentially in each section as it got invaded by CO2.The mobility of CO2 was reduced by an order of magnitude on average compared to the control. The CO2 moved slower through the core and breakthrough was delayed in the nanoparticle case. The study provides quantitative nanoparticle CO2foam mobility measurements and calculations, compared to those in control cases. Properties calculated from this study can be used to improve both EOR and CCS applications of CO2 flooding by scaling the results to the reservoir scale.

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Sipkens, T. A., N. R. Singh, K. J. Daun, N. Bizmark, M. Ioannidis, J. T. Titantah i M. Karttunen. "Time Resolved Laser Induced Incandescence for Sizing Aerosolized Iron Nanoparticles". W ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-38515.

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This paper summarizes the results of Time-Resolved Laser-Induced Incandescence (TiRe-LII) measurements of iron nanoparticles in He, Ne, Ar, N2, CO, CO2, and N2O. The iron nanoparticles are formed in solution and then aerosolized with a pneumatic atomizer using various carrier gases, so the nanoparticle size is the same for each aerosol and the TiRe-LII signal only differs due to the different thermal accommodation coefficient (TAC). Thermal accommodation coefficients for the Fe-Ar, and Fe-N2 aerosols, derived from molecular dynamics using ab initio potentials, are compared with values inferred from the TiRe-LII measurements.

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Telmadarreie, Ali, Christopher Johnsen i Steven Bryant. "A Step-Change Improvement in Fluid Diversion, Oil Sweep Efficiency, and CO2 Storage Using Novel Nanoparticle-Based Foam". W SPE Canadian Energy Technology Conference. SPE, 2022. http://dx.doi.org/10.2118/208933-ms.

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Abstract A significant amount of hydrocarbon in reservoirs is inaccessible even after deploying enhanced oil recovery methods such as gas, water, and chemical injections. Foams have been used for mobility control and fluid diversion for gas-based enhanced oil recovery, but they often lack stability in reservoir conditions. This study introduces the application of highly stable nanoparticle-based foam (nanofoam) for gas and water diversion and improving sweep efficiency and CO2 storage. A series of flow experiments in uniquely designed dual porous media were performed to investigate the performance of nanofoam in fluid diversion, sweep improvement, and CO2 storage. A permeability contrast of 5 was created to mimic the heterogeneity and fluid diversion capability of different fluids including CO2 gas, water, surfactant-based CO2 foam, and nanofoam. High permeability and low permeability porous media were saturated with water and oil (viscosity of 20 cp) respectively, mimicking a swept thief zone and bypassed oil zone. Two different types of nanoparticles were used to stabilize the nanofoam (silica-based and cellulose-based nanoparticles). These nanofoams were compared with a conventional foam stabilized only by surfactant. Due to high mobility contrast, injecting CO2 and water resulted only in displacement of water from the high permeability core, with negligible flow into the oil-saturated core. Foam was then injected with the intention of preferentially filling the high permeability core, so that subsequent CO2/water injection would be diverted into the oil-saturated core. Although surfactant foam generated relatively strong foam, it failed to divert subsequent water/CO2 into the oil-saturated core. The amount of oil recovery and additional CO2 storage was minimal. On the other hand, nanofoam (made with either type of nanoparticles) diverted both water and CO2 to the low permeability media improving oil recovery and increasing CO2 storage. Compared to pure CO2/water injection, nanofoam enhanced the incremental oil recovery by 40% of original oil in place with additional CO2 storage. This study reveals that an engineered designed nanofoam could result in step-change improvement of conventional foams performance hence delivering the results desired in field applications. A highly stable foam can play an important role to access more pore space for CO2 storage and which is inaccessible otherwise without drilling new wells.

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Rutherford, William, Wessam Elomar, A. G. Agwu Nnanna i Brian Sankowski. "An Integrated Thermoelectric Nanofluid Heat Exchanger". W ASME 2007 InterPACK Conference collocated with the ASME/JSME 2007 Thermal Engineering Heat Transfer Summer Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ipack2007-33698.

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This paper presents an experimental investigation of thermoelectric, TE, cooling system using nanofluid-based heat exchanger. The presence of nanoparticles in buoyancy-driven flows affects the thermophysical properties of the fluid and consequently alters the rate of heat transfer. The TE module is sandwiched between a heat source and the heat exchanger, with the cold side of the TEM attached to the heat source. The focus of this paper is to assess the enhancement in coefficient of performance of TEM using with 27nm Al2O3 — H2O nanofluid-based heat exchanger. Experimental simulations were performed to measure the transient and steady-state thermal response of TE to imposed isothermal condition. The volume fraction is varied between 0 to 2%. Preliminary results obtained for volume fraction of 0% (without nanoparticle) is reported in this paper. Result show that the COP is a strong function of the effectiveness of the heat exchanger and thermal contact resistance. Additional experimental runs are being conducted to show if at all, COP can be augmented using nanofluid-based heat exchanger.

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Riyaz, Najam US Sahar, Karthik Kannan, Aboubakr M. Abdullah i Kishor Kumar Sadasivuni. "Facile Synthesis of Mesoporous Silica Nanoparticles and its Electrochemical Conversion of CO2 to Fuels". W Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0094.

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The increasing amount of CO2 emissions from the industries is proving to have disastrous consequences on the environment. It would be highly beneficial if this CO2 is to be recycled and converted into useful fuel. The aim of this project involves synthesizing a suitable catalyst which can be used for the electrochemical (EC) conversion of CO2 to fuel. The developed catalyst should be mesoporous silica nanoparticles and loaded on to a metal oxide surface. The synthesis involved a relatively simple procedure of forming a homogenous mixture for the nanoparticles, drying the mixture for 2 days then loading on to the metal nitrate. Finally, multiple scans and tests were run on the synthesized sample to characterize its qualities. The results show that the synthesized mesoporous silica nanoparticles have suitable catalytic properties for electrochemical reduction of CO2 to fuel.

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Alfakher, Ahmad, i David A. DiCarlo. "Enhanced Experimental Carbon Dioxide Sweep Using Surface Coated Silica Nanoparticles as a Foaming Agent". W SPE Annual Technical Conference and Exhibition. SPE, 2021. http://dx.doi.org/10.2118/206278-ms.

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Abstract Solvent flooding is a well-established method of enhanced oil recovery (EOR), with carbon dioxide (CO2) being the most-often used solvent. As CO2 is both less viscous and less dense than the fluids it displaces, the displacement suffers from poor sweep efficiency caused by an unfavorable mobility ratio and unfavorable gravity number. Creating in-situ CO2 foam improves the sweep efficiency of CO2 floods. Another application is the injection of CO2 foam into saline aquifers for carbon capture and storage (CCS). The goal of the core flood experiments in this paper was to study the effectiveness of surface coated silica nanoparticles as an in-situ CO2 foaming agent. In each experiment, the pressure drop was measured across five separate sections in the core, as well as along the whole core. In addition, the saturation distribution in the core was calculated periodically using computed tomography (CT) scanning measurements. The experiments consisted of vertical core floods where liquid CO2 displaced brine from the top to the bottom of the core. A flood with surface coated silica nanoparticles suspended in the brine is performed in the same core and at the same conditions to a flood with no nanoparticles, and results from these floods are compared. In these experiments, breakthrough occurred 45% later with foamed CO2, and the final CO2 saturation was also 45% greater than with the unfoamed CO2. The study shows how nanoparticles stabilize the CO2 front. The results provide quantitative information on, as well as a graphical representation of, the behavior of the CO2 foam front as it advances through the core. This data can be used to upscale the behavior observed and properties calculated from the core-scale to the reservoir-scale to improve field applications of CO2 flooding.

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Yu, Jianjia, Ning Liu, Liangxiong Li i Robert L. Lee. "Generation of Nanoparticle-Stabilized Supercritical CO2 Foams". W Carbon Management Technology Conference. Carbon Management Technology Conference, 2012. http://dx.doi.org/10.7122/150849-ms.

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Machmudah, Siti, Wahyudiono, Yutaka Kuwahara, Mitsuru Sasaki i Motonobu Goto. "Pulsed laser ablation in pressurized CO2 for nanoparticles fabrication". W TENCON 2011 - 2011 IEEE Region 10 Conference. IEEE, 2011. http://dx.doi.org/10.1109/tencon.2011.6129219.

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Joshi, Seema, Manoj Kumar i Geetika Srivastava. "Optical and magnetic properties of Co2+ substituted NiFe2O4 nanoparticles". W DAE SOLID STATE PHYSICS SYMPOSIUM 2015. Author(s), 2016. http://dx.doi.org/10.1063/1.4948126.

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Raporty organizacyjne na temat "Co2P Nanoparticles"

Chistopher Roberts. Final Report for Fractionation and Separation of Polydisperse Nanoparticles into Distinct Monodisperse Fractions Using CO2 Expanded Liquids. Office of Scientific and Technical Information (OSTI), sierpień 2007. http://dx.doi.org/10.2172/935215.

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