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3. Halogen-Decorated Metal–Organic Frameworks for Efficient and Selective CO2 Capture, Separation, and Chemical Fixation with Epoxides under Mild Conditions

Author

Karmakar, Anirban, primary, Santos, Andreia A. C. D., additional, Pagliaricci, Noemi, additional, Pires, João, additional, Batista, Mary, additional, Alegria, Elisabete C. B. A., additional, Martin-Calvo, Ana, additional, Gutiérrez-Sevillano, Juan José, additional, Calero, Sofia, additional, Guedes da Silva, M. Fátima C., additional, Pettinari, Riccardo, additional, and Pombeiro, Armando J. L., additional

Published
2024
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9. Simultaneous Removal of Multipollutants (VOCs/NO/SO2) by Catalytic Ozonation Coupled with Wet Scrubbing Technology: From the Laboratory to Industrial Testing

Author

Liu, Peixi, Zhang, Yiwei, Ma, Xiaojun, Xu, Chaoqun, He, Yong, Zhu, Yanqun, Alegria, Elisabete C. B. A., Wang, Zhihua, and Pombeiro, Armando J. L.

Abstract

The simultaneous removal of multi-VOCs (C3H6O/C6H6/C7H8/C8H10) and NO/SO2by catalytic ozonation on the CoOx-CrOx/γ-Al2O3(SCC) catalyst was studied on a laboratory scale and in industrial field testing, respectively. It was discovered that the removal efficiencies of aromatic VOCs gradually increased as the excess ozone ratio (λ), the ratio of the actual number of moles of ozone to the theoretical number, increased. With the help of a wet scrubbing system, multi-VOCs and SO2can be completely removed. The removal efficiency of NO remained above 95%, and the NO2selectivity was only 2%. The applicability of the SCC catalyst at lower temperatures was verified by achieving conversion efficiencies of multiple pollutants of more than 80% at 50 °C, with the scrubbing system. In an industrial field-scale test performed in a textile mill in Anhui Province, China, it was proven that in the absence of catalyst assistance, VOCs with high molecular weight were gradually degraded and small molecules such as methanol, formaldehyde, and formic acid were generated more. Coupled with the SCC catalyst, at λ = 3, the concentrations of almost all major VOC pollutants could be degraded to <3 ppm. Analyzed by XRD, O2-TPD, H2-TPR, XPS, and ICP-OES characterizations, the excellent activity and stability of the SCC catalysts are attributed to the good dispersion of metal oxides, strong intermetallic interactions, excellent reducibility, rapid redox cycles of Cr3+/Cr6+and Co2+/Co3+, and abundant chemisorbed oxygen. The slight deactivation of the SCC catalysts utilized continuously in the textile mill may be related to the loss of active Cr6+and Co2+. The results show that the combination of catalytic ozonation technology and the wet scrubbing system can realize the efficient and simultaneous removal of multiple pollutants, providing an experimental and practical basis for further industrial application.

Published
2024
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12. A Critical Review

Author

Serafinelli, Caterina, Fantoni, Alessandro, Alegria, Elisabete C. B. A., Vieira, Manuela, CTS - Centro de Tecnologia e Sistemas, and DEE - Departamento de Engenharia Electrotécnica e de Computadores

Subjects
multiplexed detection, POC devices, readout systems, Physical and Theoretical Chemistry, plasmonic biosensors, Analytical Chemistry
Abstract

This research was supported by Portuguese national funds provided by FCT—Fundação para a Ciência e Tecnologia, through grant SFRH/BD/09347/2021, and UIDB/EEA/00066/2020, UIDP/EEA/00066/2020, LA/P/0104/2020 and by Instituto Politecnico de Lisboa through project IPL/2022/Metalogic_ISEL. Publisher Copyright: © 2023 by the authors. The recent progresses in the research of plasmonic phenomena and materials paved the route toward the development of optical sensing platforms based on metal nanostructures with a great potential to be integrated into point-of-care (POC) devices for the next generation of sensing platforms, thus enabling real-time, highly sensitive and accurate diagnostics. In this review, firstly, the optical properties of plasmonic metal nanoparticles will be illustrated, whereafter the engineering of POC platforms, such as microfluidics and readout systems, will be considered with another critical point which is surface functionalization. Attention will also be given to their potential in multiplexed analysis. Finally, the limitations for effective implementation in real diagnostics will be illustrated with a special emphasis on the latest trend in developing cutting-edge sensing systems. publishersversion published

Published
2023

16. A Comparative Study

Author

Carvalho, Ana P. G., Alegria, Elisabete C. B. A., Fantoni, Alessandro, Ferraria, Ana M., Do Rego, Ana M. Botelho, Ribeiro, Ana P. C., CTS - Centro de Tecnologia e Sistemas, and UNINOVA-Instituto de Desenvolvimento de Novas Tecnologias

Subjects
Simulations, Biosensors, Clinical Biochemistry, Biomedical Engineering, Mie theory, AuNPs, Instrumentation, Engineering (miscellaneous), Metal–graphene hybrid, Analytical Chemistry, Biotechnology
Abstract

This research was funded by EU funds through the FEDER European Regional Development Fund (project LISBOA-02-0145-FEDER-031311) project LA/P/0056/2020 of Institute of Molecular Sciences, and LA/P/0140/2020 of i4HB, project UID/EEA/00066/2020 from the Center of Technology and Systems, and from the Instituto Politécnico de Lisboa with IPL/2018/STREAM_ISEL and IPL/2020/AGE-SPReS_ISEL projects. APCR and AMF thank the Instituto Superior Técnico for the scientific employment contracts IST-ID/119/2018 and IST-ID/131/2018, respectively. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. Aiming to develop a nanoparticle-based optical biosensor using gold nanoparticles (AuNPs) synthesized using green methods and supported by carbon-based nanomaterials, we studied the role of carbon derivatives in promoting AuNPs localized surface plasmon resonance (LSPR), as well as their morphology, dispersion, and stability. Carbon derivatives are expected to work as immobi-lization platforms for AuNPs, improving their analytical performance. Gold nanoparticles (AuNPs) were prepared using an eco-friendly approach in a single step by reduction of HAuCl4·3H2O using phytochemicals (from tea) which act as both reducing and capping agents. UV–Vis spectroscopy, transmission electron microscopy (TEM), zeta potential (ζ-potential), and X-ray photoelectron spectroscopy (XPS) were used to characterize the AuNPs and nanocomposites. The addition of reduced graphene oxide (rGO) resulted in greater dispersion of AuNPs on the rGO surface compared with carbon-based nanomaterials used as a support. Differences in morphology due to the nature of the carbon support were observed and are discussed here. AuNPs/rGO seem to be the most promising candidates for the development of LSPR biosensors among the three composites we studied (AuNPs/G, AuNPs/GO, and AuNPs/rGO). Simulations based on the Mie scattering theory have been used to outline the effect of the phytochemicals on LSPR, showing that when the presence of the residuals is limited to the formation of a thin capping layer, the quality of the plasmonic resonance is not affected. A further discussion of the application framework is presented. publishersversion published

Published
2022

22. Ultrasound and Radiation-Induced Catalytic Oxidation of 1-Phenylethanol to Acetophenone with Iron-Containing Particulate Catalysts

Author

Soliman, Mohamed M. A., primary, Kopylovich, Maximilian N., additional, Alegria, Elisabete C. B. A., additional, Ribeiro, Ana P. C., additional, M. Ferraria, Ana, additional, M. Botelho do Rego, Ana, additional, Correia, Luís M. M., additional, Saraiva, Marta S., additional, and Pombeiro, Armando J. L., additional

Published
2020
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30. Mechanochemical preparation of Pd and Pt composites for Suzuki-Miyaura reactions

Author

Soliman, Mohamed M. A., Ribeiro, Ana P. C., Saraiva, Marta S., Alegria, Elisabete C. B. A., and Pombeiro, Armando J. L.

Subjects
Mechanochemical, Carbon
Abstract

Este trabalho foi financiado pelo Concurso Anual para Projetos de Investigação, Desenvolvimento, Inovação e Criação Artística (IDI&CA) 2016 do Instituto Politécnico de Lisboa. Código de referência IPL/2016/MechSynCat_ISEL The application of green, simple, time- and energy-saving mechanochemical ball-milling procedures for the dispersion of palladium and platinum salts or oxides over MWCNTs (multi-walled carbon nanotubes) and activated carbon is reported. Carbon nanotubes have exceptional properties (e.g. high mechanical strength and surface areas) which make them promising materials for various applications. In this respect, we apply dispersed palladium and platinum composites [1-2] as catalysts in the Suzuki-Miyaura reactions. Both the preparation of the dispersed materials and the catalytic Suzuki-Miyaura reactions were performed by ball-milling and the results are discussed. info:eu-repo/semantics/publishedVersion

Published
2017

34. Halogen-Decorated Metal–Organic Frameworks for Efficient and Selective CO2Capture, Separation, and Chemical Fixation with Epoxides under Mild Conditions

Author

Karmakar, Anirban, Santos, Andreia A. C. D., Pagliaricci, Noemi, Pires, João, Batista, Mary, Alegria, Elisabete C. B. A., Martin-Calvo, Ana, Gutiérrez-Sevillano, Juan José, Calero, Sofia, Guedes da Silva, M. Fátima C., Pettinari, Riccardo, and Pombeiro, Armando J. L.

Abstract

In the present work, three novel halogen-appended cadmium(II) metal–organic frameworks [Cd2(L1)2(4,4′-Bipy)2]n·4n(DMF) (1), [Cd2(L2)2(4,4′-Bipy)2]n·3n(DMF) (2), and [Cd(L3)(4,4′-Bipy)]n·2n(DMF) (3) [where L1 = 5-{(4-bromobenzyl)amino}isophthalate; L2 = 5-{(4-chlorobenzyl)amino}isophthalate; L3 = 5-{(4-fluorobenzyl)amino}isophthalate; 4,4′-Bipy = 4,4′-bipyridine; and DMF = N,N′-dimethylformamide] have been synthesized under solvothermal conditions and characterized by various analytical techniques. The single-crystal X-ray diffraction analysis demonstrated that all the MOFs feature a similar type of three-dimensional structure having a binuclear [Cd2(COO)4(N)4] secondary building block unit. Moreover, MOFs 1and 2contain one-dimensional channels along the b-axis, whereas MOF 3possesses a 1D channel along the a-axis. In these MOFs, the pores are decorated with multifunctional groups, i.e., halogen and amine. The gas adsorption analysis of these MOFs demonstrate that they display high uptake of CO2(up to 5.34 mmol/g) over N2and CH4. The isosteric heat of adsorption (Qst) value for CO2at zero loadings is in the range of 18–26 kJ mol–1. In order to understand the mechanism behind the better adsorption of CO2by our MOFs, we have also performed configurational bias Monte Carlo simulation studies, which confirm that the interaction between our MOFs and CO2is stronger compared to those with N2and CH4. Various noncovalent interactions, e.g., halogen (X)···O, Cd···O, and O···O, between CO2and the halogen atom, the Cd(II) metal center, and the carboxylate group from the MOFs are observed, respectively, which may be a reason for the higher carbon dioxide adsorption. Ideal adsorbed solution theory (IAST) calculations of MOF 1demonstrate that the obtained selectivity values for CO2/CH4(50:50) and CO2/N2(15:85) are ca. 28 and 193 at 273 K, respectively. However, upon increasing the temperature to 298 K, the selectivity value (S= 34) decreases significantly for the CO2/N2mixture. We have also calculated the breakthrough analysis curves for all the MOFs using mixtures of CO2/CH4(50:50) and CO2/N2(50:50 and 15:85) at different entering gas velocities and observed larger retention times for CO2in comparison with other gases, which also signifies the stronger interaction between our MOFs and CO2. Moreover, due to the presence of Lewis acidic metal centers, these MOFs act as heterogeneous catalysts for the CO2fixation reactions with different epoxides in the presence of tetrabutyl ammonium bromide (TBAB), for conversion into industrially valuable cyclic carbonates. These MOFs exhibit a high conversion (96–99%) of epichlorohydrin (ECH) to the corresponding cyclic carbonate 4-(chloromethyl)-1,3-dioxolan-2-one after 12 h of reaction time at 1 bar of CO2pressure, at 65 °C. The MOFs can be reused up to four cycles without compromising their structural integrity as well as without losing their activity significantly.

Published
2024
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35. Thiophene-Functionalized Cadmium(II)-Based Metal–Organic Frameworks for CO2Adsorption with Gate-Opening Effect, Separation, and Catalytic Conversion

Author

Karmakar, Anirban, Santos, Andreia A. C. D., Liu, Peixi, Gurbanov, Atash V., Pires, João, Alegria, Elisabete C. B. A., Hasanov, Khudayar I., Guedes da Silva, M. Fátima C., Wang, Zhihua, and Pombeiro, Armando J. L.

Abstract

Two new porous three-dimensional cadmium(II) metal–organic frameworks (MOFs) containing thiophene-appended carboxylate acid ligands, formulated as [Cd(L1)(4,4′-Bipy)]n.2n(DMF) (1) and [Cd(L2)(4,4′-Bipy)]n.2n(DMF) (2) [where L1 = 5-{(thiophen-2-ylmethyl)amino}isophthalate, L2 = 5-{(thiophen-3-ylmethyl)amino}isophthalate, 4,4′-Bipy = 4,4′-bipyridine, and DMF = N,N′-dimethylformamide] have been synthesized and structurally characterized. The gas adsorption analysis of the activated MOFs shows that they specifically capture CO2(uptake amount 4.36 mmol/g under 1 bar at 195 K) over N2and CH4. Moreover, both MOFs show a gate-opening–closing phenomenon, which features the S-shaped isotherms with impressive hysteretic desorption during the CO2adsorption–desorption process at 195 K. Ideal adsorbed solution theory (IAST) calculations of these MOFs displayed that the obtained selectivity values for CO2/CH4(50:50) and CO2/N2(15:85) are approximately 8.6–23 and 93–565, respectively. Configurational bias Monte Carlo simulation was performed to understand the mechanism behind the better CO2adsorption by these MOFs. Catalytic activity of the MOFs for the CO2fixation reactions with different epoxides to form cyclic carbonates were tested. These MOFs demonstrated a significantly high conversion (94–99%) of epichlorohydrin to the corresponding cyclic carbonate within 8 h of reaction time at 1 bar of CO2pressure, at 70 °C, and they can be reused up to five cycles without losing considerably their activity.

Published
2024
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41. Novel (arene)Ruthenium(II) Complexes with halogen-substituted Scorpionates: Synthesis and Structural, Electrochemical and Catalytic Studies

Author

Orbisaglia, Serena, Nicola, Corrado Di, Condello, Francesca, Palmucci, Jessica, Pettinari, Riccardo, Marchetti, Fabio, Pettinari, Claudio, Martins, Luísa M. D. R. S., Alegria, Elisabete C. B. A., Fátima C. Guedes da Silva, M. Fátima C. Guedes da Silva, Rocha, Bruno G. M., Pombeiro, Armando J. L., Skelton, Brian W., and White, Allan H.

Published
2013

42. Highly Active and Selective Supported Rhenium Catalysts for Aerobic Oxidation of n-Hexane and n-Heptane.

Author

Mishra, Gopal S., Alegria, Elisabete C. B. A., Pombeiro, Armando J. L., and Martins, Luísa M. D. R. S.

Subjects
*RHENIUM catalysts, *ALKANES, *SCORPIONATES
Abstract

A series of derivative C-scorpionate rhenium complexes, i.e., [ReCl2{NNC(O)C6H5} (Hpz)(PPh3)2] (A) (where Hpz is pyrazole), [ReCl2{NNC(O)C6H5}(Hpz)2(PPh3)] (B), [ReClF {NNC(O)C6H5}(Hpz)2(PPh3)] (C), and their precursor [ReOCl3(PPh3)2] (D), immobilized on 3-aminopropyl-functionalized silica have been prepared and used for neat O2 oxidation of n-hexane and n-heptane mainly to the corresponding alcohols and, in lower amounts, ketones. The supported catalyst C, with fluoro- and diazenido-ligands, exhibits the highest activity for both alkanes (overall turnover numbers (TONs) up to 3.8 × 103 and 2.5 × 103, for n-hexane and n-heptane, respectively) and can be reused in consecutive catalytic cycles. Improved conversion was observed after addition of hetero-carboxylate co-catalysts. A free-radical-based mechanism is proposed to explain the product formation. [ABSTRACT FROM AUTHOR]

Published
2018
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43. A Simulation Study of Surface Plasmons in Metallic Nanoparticles: Dependence on the Properties of an Embedding a-Si:H Matrix.

Author

Fantoni, Alessandro, Fernandes, Miguel, Vygranenko, Yuri, Louro, Paula, Vieira, Manuela, Alegria, Elisabete C. B. A., Ribeiro, Ana, and Texeira, Daniela

Subjects
METAL nanoparticles, SURFACE plasmons, PLASMONS (Physics), AMORPHOUS silicon, MIE scattering
Abstract

The development and realization of a plasmonic structure based on the LSP interaction of metal nanoparticles with an embedding matrix of amorphous silicon is proposed. As a planned application, this structure will need to be usable as the basis for a sensor device applied in biomedical applications, after proper functionalization with selective antibodies. The final sensor structure needs to be low-cost, compact, and disposable. The study reported in this paper aims to analyze varied materials for nanoparticles embedded in an amorphous silico matrix. Metals ofinterest for nanoparticles composition are aluminum and gold. As a comparison term, a non-plasmonic material like alumina, resulting from oxidation of Al nanoparticles, is also considered. As a preliminary approach to this device, we study in this work the optical properties of spherical metal nanoparticles embedded in an amorphous silicon matrix, as a function of size and metal type. Following an analysis based on the exact solution of the Mie theory, experimental measurements realized with arrays of metal nanoparticles are compared with the simulations. [ABSTRACT FROM AUTHOR]

Published
2018
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44. New Trendy Magnetic C-Scorpionate Iron Catalyst and Its Performance towards Cyclohexane Oxidation.

Author

Ribeiro, Ana P. C., Matias, Inês A. S., Alegria, Elisabete C. B. A., Ferraria, Ana M., Botelho do Rego, Ana M., Pombeiro, Armando J. L., and Martins, Luísa M. D. R. S.

Subjects
SCORPIONATES, IRON catalysts, OXIDATION of cyclohexane
Abstract

For the first time, a magnetic C-scorpionate catalyst was prepared from the iron(II) complex [FeCl2{κ3-HC(pz)3}] (pz = pyrazol-1-yl) and ferrite, using the sustainable mechanochemical synthetic procedure. Its catalytic activity for the cyclohexane oxidation with tert-butyl hydroperoxide (TBHP) was evaluated in different conditions, namely under microwave irradiation and under the effect of an external magnetic field. The use of such magnetic conditions significantly shifted the catalyst alcohol/ketone selectivity, thus revealing a promising, easy new protocol for tuning selectivity in important catalytic processes. [ABSTRACT FROM AUTHOR]

Published
2018
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46. Catalytic Performance of Fe(II)-Scorpionate Complexes towards Cyclohexane Oxidation in Organic, Ionic Liquid and/or Supercritical CO2 Media: A Comparative Study.

Author

Ribeiro, Ana P. C., Martins, Luísa M. D. R. S., Alegria, Elisabete C. B. A., Matias, Inês A. S., Duarte, Tiago A. G., and Pombeiro, Armando J. L.

Subjects
IONIC liquids, METAL complexes, ACETONITRILE, CYCLOHEXANE
Abstract

The catalytic activity of the iron(II) C-scorpionate complexes [FeCl2{HC(pz)3}] 1 (pz = pyrazol-1-yl) and [FeCl2{HOCH2C(pz)3}] 2, and of their precursor FeCl2·2H2O 3, towards cyclohexane oxidation with tert-butyl hydroperoxide was evaluated and compared in different media: acetonitrile, ionic liquids (1-butyl-3-methylimidazolium hexafluorophosphate, [bmim][PF6], and 1-butyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate, [bmim][FAP]), supercritical carbon dioxide (scCO2), and scCO2/[bmim][X] (X = PF6 or FAP) mixtures. The use of such alternative solvents led to efficient and selective protocols for the oxidation of cyclohexane. Moreover, tuning the alcohol/ketone selectivity was possible by choosing the suitable solvent. [ABSTRACT FROM AUTHOR]

Published
2017
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47. Tetranuclear Copper(II) Complexes with Macrocyclic and Open‐Chain Disiloxane Ligands as Catalyst Precursors for Hydrocarboxylation and Oxidation of Alkanes and 1‐Phenylethanol

Author

Zaltariov, Mirela‐Fernanda, primary, Alexandru, Mihaela, additional, Cazacu, Maria, additional, Shova, Sergiu, additional, Novitchi, Ghenadie, additional, Train, Cyrille, additional, Dobrov, Anatolie, additional, Kirillova, Marina V., additional, Alegria, Elisabete C. B. A., additional, Pombeiro, Armando J. L., additional, and Arion, Vladimir B., additional

Published
2014
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48. New RuII(arene) Complexes with Halogen‐Substituted Bis‐ and Tris(pyrazol‐1‐yl)borate Ligands

Author

Orbisaglia, Serena, primary, Di Nicola, Corrado, additional, Marchetti, Fabio, additional, Pettinari, Claudio, additional, Pettinari, Riccardo, additional, Martins, Luísa M. D. R. S., additional, Alegria, Elisabete C. B. A., additional, Guedes da Silva, M. Fátima C., additional, Rocha, Bruno G. M., additional, Kuznetsov, Maxim L., additional, Pombeiro, Armando J. L., additional, Skelton, Brian W., additional, Sobolev, Alexandre N., additional, and White, Allan H., additional

Published
2014
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