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59. HKUST-1 Metal–Organic Framework Nanoparticle/Graphene Oxide Nanocomposite Aerogels for CO2 and CH4 Adsorption and Separation

Author

Rosado, Albert, primary, Borrás, Alejandro, additional, Fraile, Julio, additional, Navarro, Jorge A. R., additional, Suárez-García, Fabián, additional, Stylianou, Kyriakos C., additional, López-Periago, Ana M., additional, Planas, José Giner, additional, Domingo, Concepción, additional, and Yazdi, Amirali, additional

Published
2021
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62. Color-tunable and high quantum-yield luminescence from a biomolecule-inspired single species emitter of white light

Author

Ebrahim, Fatmah Mish, primary, Fumanal, Maria, additional, Gladysiak, Andrzej, additional, Kadioglu, Ozge, additional, Jablonka, Kevin, additional, Ongari, Daniele, additional, Mace, Amber, additional, Shyshkanov, Serhii, additional, Saris, Seryio, additional, Ireland, Christopher, additional, Dyson, Paul, additional, Stylianou, Kyriakos, additional, and Smit, Berend, additional

Published
2021
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63. A Highly Water-Stable meta-Carborane-Based Copper Metal–Organic Framework for Efficient High-Temperature Butanol Separation

Author

Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, National Natural Science Foundation of China, Oregon State University, Gan, Lei, Chidambaram, Arunraj, Fonquernie, Pol G., Light, Mark E., Choquesillo-Lazarte, Duane, Huang, Hongliang, Solano, Eduardo, Fraile, Julio, Viñas, Clara, Teixidor, Francesc, Navarro, Jorge A.R., Stylianou, Kyriakos C., Giner Planas, José, Ministerio de Economía y Competitividad (España), Generalitat de Catalunya, National Natural Science Foundation of China, Oregon State University, Gan, Lei, Chidambaram, Arunraj, Fonquernie, Pol G., Light, Mark E., Choquesillo-Lazarte, Duane, Huang, Hongliang, Solano, Eduardo, Fraile, Julio, Viñas, Clara, Teixidor, Francesc, Navarro, Jorge A.R., Stylianou, Kyriakos C., and Giner Planas, José

Abstract

Biofuels are considered sustainable and renewable alternatives to conventional fossil fuels. Biobutanol has recently emerged as an attractive option compared to bioethanol and biodiesel, but a significant challenge in its production lies in the separation stage. The current industrial process for the production of biobutanol includes the ABE (acetone–butanol–ethanol) fermentation process from biomass; the resulting fermentation broth has a butanol concentration of no more than 2 wt% (the rest is essentially water). Therefore, the development of a cost-effective process for separation of butanol from dilute aqueous solutions is highly desirable. The use of porous materials for the adsorptive separation of ABE mixtures is considered a highly promising route, as these materials can potentially have high affinities for alcohols and low affinities for water. To date, zeolites have been tested toward this separation, but their hydrophilic nature makes them highly incompetent for this application. The use of metal–organic frameworks (MOFs) is an apparent solution; however, their low hydrolytic stabilities hinder their implementation in this application. So far, a few nanoporous zeolitic imidazolate frameworks (ZIFs) have shown excellent potential for butanol separation due to their good hydrolytic and thermal stabilities. Herein, we present a novel, porous, and hydrophobic MOF based on copper ions and carborane–carboxylate ligands, mCB-MOF-1, for butanol recovery. mCB-MOF-1 exhibits excellent stability when immersed in organic solvents, water at 90 °C for at least two months, and acidic and basic aqueous solutions. We found that, like ZIF-8, mCB-MOF-1 is non-porous to water (type II isotherm), but it has higher affinity for ethanol, butanol, and acetone compared to ZIF-8, as suggested by the shape of the vapor isotherms at the crucial low-pressure region. This is reflected in the separation of a realistic ABE mixture in which mCB-MOF-1 recovers butanol more efficiently com

Published
2020

69. A Highly Water-Stable meta-Carborane-Based Copper Metal–Organic Framework for Efficient High-Temperature Butanol Separation

Author

Gan, Lei, primary, Chidambaram, Arunraj, additional, Fonquernie, Pol G., additional, Light, Mark E., additional, Choquesillo-Lazarte, Duane, additional, Huang, Hongliang, additional, Solano, Eduardo, additional, Fraile, Julio, additional, Viñas, Clara, additional, Teixidor, Francesc, additional, Navarro, Jorge A. R., additional, Stylianou, Kyriakos C., additional, and Planas, José G., additional

Published
2020
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78. Lanthanide metal–organic frameworks for the fixation of CO2 under aqueous-rich and mixed-gas conditions.

Author

Le, David H., Loughan, Ryan P., Gładysiak, Andrzej, Rampal, Nakul, Brooks, Isabelle A., Park, Ah-Hyung Alissa, Fairen-Jimenez, David, and Stylianou, Kyriakos C.

Abstract

The development of effective catalysts is one of the big challenges associated with a new circular carbon economy addressing climate change. The targeted synthesis of robust and recyclable catalysts can be made possible through elucidation of the molecular interactions between the active sites in metal–organic frameworks (MOFs) with potentially reactive molecules. Herein, we present the use of lanthanide (Ln)-based MOFs – [Ln(HTCPB)] Ln: Ce, Nd, Sm, Eu, Tb, and Dy; H4TCPB: 1,2,4,5-tetrakis(4-carboxyphenyl)benzene – as catalysts for the conversion of CO2 to value-added products. Using these MOFs, we describe the fixation of CO2 into the epoxy ring of propylene oxide for the production of cyclic carbonates. Structural analysis of the propylene oxide (PO)-loaded MOF revealed the binding of PO to Ce3+, confirming the key role of open Ce3+ sites in reducing the activation energy of the PO chemical transformation. The ring-opening of the PO molecule is followed by the insertion of one molecule of CO2, leading to the formation of the propylene carbonate (PC) molecule. The channels present in the MOF structure allow for diffusion of CO2 from the environment to the open Ce3+ sites and that of PC in the opposite direction, thus upholding the catalytic process. [Ce(HTCPB)] exhibited high catalytic activity toward PC production with a turn-over frequency (TOF) = 20.2 h−1, one of the highest reported. The catalyst showed no catalytic deterioration after three cycles and maintained a comparable catalytic activity when aqueous-rich conditions and gas CO2/N2 and CO2/CH4 mixtures were used, highlighting that non-contributing gas molecules or impurities do not affect the catalytic activity of the MOF. Catalytic experiments using [Ln(HTCPB)] demonstrated that the rate of CO2 conversion decreased by decreasing the ionic radii of the Ln used. Grand canonical Monte Carlo simulations (GCMC) and topographic steric maps suggested that the activity of a catalyst can be tuned by manipulating the ionic size and partial charge of the lanthanides, and steric properties of the active site. Our study highlights the engineering of efficient catalysts capable of converting CO2 into value-added products directly from its wet and mixed-composition streams (e.g., waste flue gas and biogas). [ABSTRACT FROM AUTHOR]

Published
2022
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79. Data-driven design of metal-organic frameworks for wet flue gas CO2 capture

Author

Boyd, Peter G., Chidambaram, Arunraj, Garcia-Diez, Enrique, Ireland, Christopher P., Daff, Thomas D., Bounds, Richard, Gladysiak, Andrzej, Schouwink, Pascal, Moosavi, Seyed Mohamad, Maroto-Valer, M. Mercedes, Reimer, Jeffrey A., Navarro, Jorge A. R., Woo, Tom K., Garcia, Susana, Stylianou, Kyriakos C., Smit, Berend, Daff, Thomas [0000-0003-4837-4143], and Apollo - University of Cambridge Repository

Subjects
Climate Action, pressure, 13 Climate Action, 34 Chemical Sciences, mil-53, General Science & Technology, 4004 Chemical Engineering, swing adsorption, carbon-dioxide capture, 40 Engineering
Abstract

Limiting the increase of CO2 in the atmosphere is one of the largest challenges of our generation(1). Because carbon capture and storage is one of the few viable technologies that can mitigate current CO2 emissions(2), much effort is focused on developing solid adsorbents that can efficiently capture CO2 from flue gases emitted from anthropogenic sources(3). One class of materials that has attracted considerable interest in this context is metal-organic frameworks (MOFs), in which the careful combination of organic ligands with metal-ion nodes can, in principle, give rise to innumerable structurally and chemically distinct nanoporous MOFs. However, many MOFs that are optimized for the separation of CO2 from nitrogen(4-7) do not perform well when using realistic flue gas that contains water, because water competes with CO2 for the same adsorption sites and thereby causes the materials to lose their selectivity. Although flue gases can be dried, this renders the capture process prohibitively expensive(8,9). Here we show that data mining of a computational screening library of over 300,000 MOFs can identify different classes of strong CO2-binding sites-which we term `adsorbaphores'-that endow MOFs with CO2/N-2 selectivity that persists in wet flue gases. We subsequently synthesized two water-stable MOFs containing the most hydrophobic adsorbaphore, and found that their carbon-capture performance is not affected by water and outperforms that of some commercial materials. Testing the performance of these MOFs in an industrial setting and consideration of the full capture process-including the targeted CO2 sink, such as geological storage or serving as a carbon source for the chemical industry-will be necessary to identify the optimal separation material.

Published
2019

80. Electronic metal–organic framework sensors

Author

Chidambaram, Arunraj, C. Stylianou, Kyriakos, Chidambaram, Arunraj, and C. Stylianou, Kyriakos

Abstract

Metal–organic frameworks (MOFs), a class of crystalline and porous materials, are synthesized through the self-assembly of organic ligands and inorganic metal nodes (ions or clusters). For the past few years, MOFs have been in the limelight due to their structural versatility and tuneable porosity, which have provided us with a promising outlook in several applications, such as gas storage and separation, sensing, drug delivery and catalysis. The recent intriguing demonstrations of MOF-based electronic devices have attracted considerable attention. This development is considered to be a significant achievement as it has transcended barriers such as the low conductivity or insulating properties of MOFs and the fabrication of MOF devices. Thus, the motivation of this review is to showcase the potential of MOFs as electronic sensor materials for the detection of molecules in the gas/vapour phase and highlight that MOFs can outperform other solid-state sensing materials. We discuss the performance of several MOFs that have been utilised for sensing a number of different gases and vapours such as humidity, volatile organic compounds, aldehydes, alkanes, trimethylamine, ammonia, hydrogen sulphide, nitric oxide and the nerve agent sarin. A literature overview on the four different types of electronic MOF sensor devices for the detection of molecules in the gas/vapour phase – impedimetric, chemicapacitive, work function based sensors with the Kelvin probe configuration and chemiresistive type sensors – is provided, wherein MOFs were incorporated as the (active) sensing layer.

Published
2019
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81. HKUST‑1 Metal–Organic Framework Nanoparticle/Graphene Oxide Nanocomposite Aerogels for CO2 and CH4 Adsorption and Separation.

Author

Rosado, Albert, Borrás, Alejandro, Fraile, Julio, Navarro, Jorge A. R., Suárez-García, Fabián, Stylianou, Kyriakos C., López-Periago, Ana M., Planas, José Giner, Domingo, Concepción, and Yazdi, Amirali

Abstract

The development of nanostructured composites made of metal–organic frameworks (MOFs) and graphene-based components, including exfoliated nanoplates of graphene oxide (GO) or reduced (rGO) graphene oxide, is an area of great interest in gas storage and separation. To improve the industrial viability, it is commonly demanded to build these nanocomposites with the shape of compact units, such as monoliths, foams, pellets, or films. Methods to generate those 3D nanocomposites involving rGO are abundant; however, they become scarce when GO is the desired support due to the difficulty in maintaining the carbon matrix oxidized during the structuration process. In this work, a methodology based on the use of supercritical CO2 (scCO2) is described for the synthesis of nanocomposites involving a discontinuous MOF phase, e.g. nanoparticles (NPs) of HKUST-1, decorating the surface of a continuous GO matrix, with surface oxygen groups favoring MOF attachment. The use of this new supercritical methodology allows the nanostructuration of the composite in the form of 3D aerogels while avoiding the reduction of GO. Enhanced values of textural properties, determined by low-temperature N2 adsorption–desorption, were observed for the nanocomposites in comparison to the values calculated for similar physical mixtures, highlighting an increase of 40–45% in the value of the surface area for samples with a high percentage of HKUST-1. Moreover, the composite aerogels, displaying a type II isotherm, outperform pristine HKUST-1 in regard to the CH4 practical working capacity at high pressure. Particularly, a composite exhibiting more than 2-fold the working capacity of net HKUST-1 NPs was obtained. Columns involving the composite aerogel as the stationary phase were used to study the separation of N2/CO2 and CH4/CO2 gas mixtures. The results showed a high selectivity of the nanostructured HKUST-1@GO composites for CO2, with breakthrough times of ca. 20 min g–1 and stable cyclic operations. [ABSTRACT FROM AUTHOR]

Published
2021
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89. Ruthenium-based metal–organic framework catalyst for CO2fixation onto epoxidesElectronic supplementary information (ESI) available. See DOI: https://doi.org/10.1039/d2cy01170k

Author

Ho, James, Nord, Makenzie T., Stafford, Jared P., and Stylianou, Kyriakos C.

Abstract

The formation of value-added cyclic carbonates by the cycloaddition of CO2to various epoxides is investigated using a ruthenium-based metal–organic framework (Ru-HKUST-1). The Ru-HKUST-1 catalyst demonstrates catalytic activity for CO2fixation with a high substrate concentration under mild conditions, and is shown to be more active than the traditional Cu-HKUST-1.

Published
2022
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90. Photocatalytic hydrogen generation from a visible-light responsive metal-organic framework system : the impact of nickel phosphide nanoparticles

Author

Kampouri, Stavroula, Nguyen, Tu N., Ireland, Christopher P., Valizadeh, Bardiya, Ebrahim, Fatmah Mish, Capano, Gloria, Ongari, Daniele, Mace, Amber, Guijarro, Nestor, Sivula, Kevin, Sienkiewicz, Andrzej, Forró, László, Smit, Berend, Stylianou, Kyriakos C., Kampouri, Stavroula, Nguyen, Tu N., Ireland, Christopher P., Valizadeh, Bardiya, Ebrahim, Fatmah Mish, Capano, Gloria, Ongari, Daniele, Mace, Amber, Guijarro, Nestor, Sivula, Kevin, Sienkiewicz, Andrzej, Forró, László, Smit, Berend, and Stylianou, Kyriakos C.

Abstract

Herein, we report the performance of a photocatalytic system based on visible-light active MIL-125-NH2 mixed with nickel phosphide (Ni2P) nanoparticles. This combination boosts the H-2 evolution rate to an outstanding value of 894 mu mol h(-1) g(-1) under visible-light irradiation, which is among the highest H-2 evolution rates reported to date for metal-organic frameworks (MOFs). The H-2 generation rate exhibited by Ni2P/MIL-125-NH2 is almost 3 times higher than that of the Pt/MIL-125-NH2 system, highlighting the impact of the co-catalyst on photocatalytic water splitting. Additionally, our system outperforms the Ni2P/TiO2 system under UV-vis irradiation. The exceptional performance of Ni2P/MIL-125-NH2 is due to the efficient transfer of photogenerated electrons from MIL-125-NH2 to Ni2P, high intrinsic activity of Ni2P and exceptional synergy between them. This system exhibits the highest apparent quantum yields of 27.0 and 6.6% at 400 and 450 nm, respectively, ever reported for MOFs.

Published
2018
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92. CO2 Methanation via Amino Alcohol Relay Molecules Employing a Ruthenium Nanoparticle/Metal Organic Framework Catalyst.

Author

Cui, Xinjiang, Shyshkanov, Serhii, Nguyen, Tu N., Chidambaram, Arunraj, Fei, Zhaofu, Stylianou, Kyriakos C., and Dyson, Paul J.

Subjects
METAL-organic frameworks, AMINO alcohols, METHANATION, CATALYSTS, RUTHENIUM, RUTHENIUM catalysts, MOLECULES
Abstract

Methanation of carbon dioxide (CO2) is attractive within the context of a renewable energy refinery. Herein, we report an indirect methanation method that harnesses amino alcohols as relay molecules in combination with a catalyst comprising ruthenium nanoparticles (NPs) immobilized on a Lewis acidic and robust metal–organic framework (MOF). The Ru NPs are well dispersed on the surface of the MOF crystals and have a narrow size distribution. The catalyst efficiently transforms amino alcohols to oxazolidinones (upon reaction with CO2) and then to methane (upon reaction with hydrogen), simultaneously regenerating the amino alcohol relay molecule. This protocol provides a sustainable, indirect way for CO2 methanation as the process can be repeated multiple times. [ABSTRACT FROM AUTHOR]

Published
2020
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