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Andres, B., Dahlström, C., Blomquist, N., Norgren, M. & Olin, H. (2018). Cellulose binders for electric double-layer capacitor electrodes: The influence of cellulose quality on electrical properties. Materials & design, 141, 342-349
Open this publication in new window or tab >>Cellulose binders for electric double-layer capacitor electrodes: The influence of cellulose quality on electrical properties
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2018 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 141, p. 342-349Article in journal (Refereed) Published
Abstract [en]

Cellulose derivatives are widely used as binders and dispersing agents in different applications. Binders composed of cellulose are an environmentally friendly alternative to oil-based polymer binding agents. Previously, we reported the use of cellulose nanofibers (CNFs) as binders in electrodes for electric double-layer capacitors (EDLCs). In addition to good mechanical stability, we demonstrated that CNFs enhanced the electrical performance of the electrodes. However, cellulose fibers can cover a broad range of length scales, and the quality requirements from an electrode perspective have not been thoroughly investigated. To evaluate the influence of fiber quality on electrode properties, we tested seven samples with different fiber dimensions that are based on the same kraft pulp. To capture the length scale from fibers to nanofibrils, we evaluated the performance of the untreated kraft pulp, refined fibers, microfibrillated cellulose (MFC) and CNFs. Electrodes with kraft pulp or refined fibers showed the lowest electrical resistivity. The specific capacitances of all EDLCs were surprisingly similar, but slightly lower for the EDLC with CNFs. The same electrode sample with CNFs also showed a slightly higher equivalent series resistance (ESR), compared to those of the other EDLCs. Graphite dispersions with MFC showed the best dispersion stability. 

Keywords
Cellulose, Electric double-layer capacitor, Graphite, Nanocellulose, Nanocomposite, Supercapacitor
National Category
Chemical Engineering
Identifiers
urn:nbn:se:miun:diva-32766 (URN)10.1016/j.matdes.2017.12.041 (DOI)000424945300031 ()2-s2.0-85040002856 (Scopus ID)
Available from: 2018-01-30 Created: 2018-01-30 Last updated: 2018-07-19Bibliographically approved
Eivazihollagh, A., Norgren, M., Dahlström, C. & Edlund, H. (2018). Controlled Synthesis of Cu and Cu2O NPs and Incorporation of Octahedral Cu2O NPs in Cellulose II Films. Nanomaterials, 8(4), Article ID 238.
Open this publication in new window or tab >>Controlled Synthesis of Cu and Cu2O NPs and Incorporation of Octahedral Cu2O NPs in Cellulose II Films
2018 (English)In: Nanomaterials, ISSN 2079-4991, Vol. 8, no 4, article id 238Article in journal (Refereed) Published
Abstract [en]

In this study, Cu and Cu2O nanoparticles (NPs) were synthesized through chemical reduction of soluble copper-chelating ligand complexes using formaldehyde as a reducing agent. The influence of various chelating ligands, such as ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and a surface-active derivative of DTPA (C12-DTPA), as well as surfactants (i.e., hexadecyltrimethylammonium bromide (CTAB), dodecyltrimethylammonium chloride (DoTAC), sodium dodecyl sulfate (SDS), and dimethyldodecylamine-N-oxide (DDAO)), on morphology and the composition of produced NPs was investigated. In the absence of surfactants, spherical copper particles with polycrystalline structure could be obtained. X-ray diffraction (XRD) analysis revealed that, in the presence of EDTA, the synthesized NPs are mainly composed of Cu with a crystallite size on the order of 35 nm, while with DTPA and C12-DTPA, Cu2O is also present in the NPs as a minority phase. The addition of ionic surfactants to the copper–EDTA complex solution before reduction resulted in smaller spherical particles, mainly composed of Cu. However, when DDAO was added, pure Cu2O nano-octahedrons were formed, as verified by high-resolution scanning electron microscopy (HR-SEM) and XRD. Furthermore, a hybrid material could be successfully prepared by mixing the octahedral Cu2O NPs with cellulose dissolved in a LiOH/urea solvent system, followed by spin-coating on silica wafers. It is expected that this simple and scalable route to prepare hybrid materials could be applied to a variety of possible applications.

Keywords
copper nanoparticles; cuprous oxide nano-octahedrons; hybrid material; regenerated cellulose; chemical reduction; chelating agent; surfactant
National Category
Nano Technology Chemical Engineering Materials Engineering
Identifiers
urn:nbn:se:miun:diva-33497 (URN)10.3390/nano8040238 (DOI)000434889100059 ()2-s2.0-85045875998 (Scopus ID)
Available from: 2018-04-16 Created: 2018-04-16 Last updated: 2018-07-04Bibliographically approved
Ibrahem, I., Iqbal, M. N., Verho, O., Eivazihollagh, A., Olsén, P., Edlund, H., . . . Johnston, E. V. (2018). Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols. ChemNanoMat, 4(1), 71-75
Open this publication in new window or tab >>Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols
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2018 (English)In: ChemNanoMat, ISSN 2199-692X, Vol. 4, no 1, p. 71-75Article in journal (Refereed) Published
Abstract [en]

Herein, we report on the facile synthesis of a heterogeneous copper nanocatalyst and its combination with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) for the aerobic oxidation of alcohols to their corresponding carbonyl compounds. This low cost copper nanocatalyst was found to exhibit excellent recyclability, making it a highly attractive catalytic system from an economical and environmental point of view. Extensive characterization of the catalyst by a number of techniques revealed that it was comprised of well-dispersed Cu(I/II) nanoparticles with an average size of around 6nm.

Keywords
Alcohol oxidation, Copper nanoparticles, Green chemistry, Heterogeneous catalysis, TEMPO
National Category
Chemical Sciences
Identifiers
urn:nbn:se:miun:diva-32328 (URN)10.1002/cnma.201700309 (DOI)000419237800011 ()2-s2.0-85033664510 (Scopus ID)
Note

Version of record online: 14 November 2017

Available from: 2017-12-07 Created: 2017-12-07 Last updated: 2018-06-28Bibliographically approved
Eivazihollagh, A., Bäckström, J., Norgren, M. & Edlund, H. (2018). Electrochemical recovery of copper complexed by DTPA and C12-DTPA from aqueous solution using a membrane cell. Journal of chemical technology and biotechnology (1986), 93(5), 1421-1431
Open this publication in new window or tab >>Electrochemical recovery of copper complexed by DTPA and C12-DTPA from aqueous solution using a membrane cell
2018 (English)In: Journal of chemical technology and biotechnology (1986), ISSN 0268-2575, E-ISSN 1097-4660, Vol. 93, no 5, p. 1421-1431Article in journal (Refereed) Published
Abstract [en]

BACKGROUND

The electrochemical recovery of copper from DTPA and C12-DTPA (a surface-active derivative of DTPA) complex solutions was investigated in a membrane flow cell. Electrolysis time, solution flow rate, applied current density, and solution pH were evaluated.

RESULTS

The chelating surfactant C12-DTPA can promote the kinetics of copper electrodeposition more than DTPA depending on the experimental conditions. At a current density of 30 A m–2, a solution flow rate of 0.6 L min–1, and pH 10 after 180 min treatment, the copper recovery and current efficiency were 50% and 43.3%, respectively, in the Cu(II)-DTPA system and about 65% and 53.6%, respectively, in the Cu(II)-C12-DTPA system. The differences in the amount of recovery could be explained in terms of differences in the diffusion of copper complexes with DTPA and C12-DTPA to the cathode, as well as their solution behavior and pH-dependent conditional stability constants (log10 K’CuDTPA3-).

CONCLUSION

Electrochemical methods could be effectively combined with foam flotation for the chelating surfactant C12-DTPA, to recover copper and C12-DTPA. This makes the overall treatment more sustainable, and can be helpful in complying with the increasingly stringent environmental regulations

National Category
Chemical Sciences
Identifiers
urn:nbn:se:miun:diva-32251 (URN)10.1002/jctb.5510 (DOI)000429714500022 ()
Note

Available from: 2017-12-05 Created: 2017-12-05 Last updated: 2018-06-28Bibliographically approved
Forsberg, V. & Norgren, M. (2018). Green materials for inkjet printing of 2D materials and transparent electronics. In: : . Paper presented at 10th Anniversary Symposium on Liquid Phase Exfoliation, Irland, August 2, 2018.
Open this publication in new window or tab >>Green materials for inkjet printing of 2D materials and transparent electronics
2018 (English)Conference paper, Poster (with or without abstract) (Other (popular science, discussion, etc.))
National Category
Materials Chemistry Paper, Pulp and Fiber Technology Polymer Technologies
Identifiers
urn:nbn:se:miun:diva-34234 (URN)
Conference
10th Anniversary Symposium on Liquid Phase Exfoliation, Irland, August 2, 2018
Projects
KM2 Sol
Funder
Knowledge Foundation
Available from: 2018-08-13 Created: 2018-08-13 Last updated: 2018-08-16Bibliographically approved
Forsberg, V., Andersson, H., Engholm, M., Thungström, G., Zhang, R., Hummelgård, M., . . . Norgren, M. (2018). Photodetector of multilayer exfoliated MoS2 deposited on polyimide films. In: : . Paper presented at 20th International Workshop on Radiation Imaging Detectors, Sundsvall, 24-28 June, 2018.
Open this publication in new window or tab >>Photodetector of multilayer exfoliated MoS2 deposited on polyimide films
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2018 (English)Conference paper, Poster (with or without abstract) (Other academic)
Abstract [en]

We fabricated a photodetector based on multilayer molybdenum disulfide (MoS2) by micromechanical cleavage of a molybdenite crystal using a polyimide film. We deposited 40 nm of gold by vacuum sputtering and copper tape was used for the contacts.  Without any surface treatment, we achieved high responsivity at different incident optical power. The calculated responsivity was 23 mA/W of incident optical power in the range between 400 and 800 nm. For the responsivity measurement it was estimated that MoS2 have a bandgap of 1.6 eV, which lies between monolayer and multilayer films. The thickness of the MoS2 thin film was determined by Raman spectroscopy evaluating the difference between the in plane  and out of plane  Raman modes. The measurement of IV curves indicated Ohmic contacts in respect to the Au regardless of the incident optical power. Our device fabrication was much simpler than previous reported devices and can be used to test the light absorption and luminescence capabilities of exfoliated MoS2.

Keywords
Photodetector, MoS2
National Category
Chemical Engineering Materials Engineering Physical Sciences
Identifiers
urn:nbn:se:miun:diva-34035 (URN)
Conference
20th International Workshop on Radiation Imaging Detectors, Sundsvall, 24-28 June, 2018
Funder
Knowledge Foundation, 2600364
Available from: 2018-06-29 Created: 2018-06-29 Last updated: 2018-08-16Bibliographically approved
Eivazihollagh, A., Bäckström, J., Norgren, M. & Edlund, H. (2017). Influences of the operational variables on electrochemical treatment of chelated Cu(II) in alkaline solutions using a membrane cell. Journal of chemical technology and biotechnology (1986), 92(6), 1436-1445
Open this publication in new window or tab >>Influences of the operational variables on electrochemical treatment of chelated Cu(II) in alkaline solutions using a membrane cell
2017 (English)In: Journal of chemical technology and biotechnology (1986), ISSN 0268-2575, E-ISSN 1097-4660, Vol. 92, no 6, p. 1436-1445Article in journal, Editorial material (Refereed) Published
Abstract [en]

BACKGROUND

The electrochemical recovery of copper and chelating agent from their complex solution using a membrane flow cell was investigated. The parameters electrolysis time, solution pH, current density, and temperature were investigated.

RESULTS

Electrochemical investigation indicated that chelating ligands can be recovered by the electrodeposition of copper ions on the cathode. For copper and EDTA recovery, the results indicated that recovery efficiency was affected by time, current density, and temperature. The recovery process was not influenced by pH in the range studied (pH 8–12), which can be explained by the low variation in the conditional stability constant, i.e. Δlog10 K' ≤ 0.7, over the pH range. However, when NTA, EDTA, and DTPA were compared, the results indicated that the recovery efficiency decreased as the conditional stability constant of the chelating agent–Cu(II) complex increased. The maximum current efficiency of copper and EDTA recovery after 5 h of treatment was approximately 85%, whereas the recovery was 80% of the initial concentration (0.05 mol L−1) at a current density of 1 A dm−2, temperature of 333 K, and pH of 10.

CONCLUSION

Relatively high recovery efficiency makes the process fairly sustainable and hinders the discharge of copper ions and chelating ligands as pollutants into the environment. 

Keywords
electrochemistry, heavy metals, recovery, waste-water, hydrometallurgy
National Category
Chemical Sciences
Identifiers
urn:nbn:se:miun:diva-29558 (URN)10.1002/jctb.5141 (DOI)000403025100035 ()2-s2.0-85006827367 (Scopus ID)
Available from: 2016-12-14 Created: 2016-12-14 Last updated: 2018-06-28Bibliographically approved
Eivazihollagh, A., Bäckström, J., Dahlström, C., Carlsson, F., Ibrahem, I., Lindman, B., . . . Norgren, M. (2017). One-pot synthesis of cellulose-templated copper nanoparticles with antibacterial properties. Materials letters (General ed.), 187, 170-172
Open this publication in new window or tab >>One-pot synthesis of cellulose-templated copper nanoparticles with antibacterial properties
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2017 (English)In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 187, p. 170-172Article in journal (Refereed) Published
Abstract [en]

We report a facile in situ synthesis of spherical copper nanoparticles (NPs) templated by a gelled cellulose II matrix under alkaline aqueous reaction conditions. In under 20 min, the hybrid material could be obtained in a one-pot reaction. Field-emission scanning electron microscopy (FE-SEM) revealed that the polycrystalline NPs of 200–500 nm were well distributed in the regenerated cellulose matrix. The average Cu crystallite size was of the order of 20 nm, as estimated from both X-ray diffraction (XRD) and FE-SEM. XRD data also indicated that the composite contained up to approximately 20% Cu2O. In suspensions containing the hybrid material, growth of Escerichia coli and Staphylococcus aureus strains was inhibited by 80% and 95%, respectively, after 72 h. The synthesis procedure offers a general approach to designing various low-cost hybrid materials of almost any shape, and the concept could be extended to utilization areas such as catalysis, functional textiles, and food packaging as well as to electronic applications.

Keywords
One-pot synthesis, Copper nanoparticles, Cellulose, Hybrid material, Antibacterial properties
National Category
Nano Technology Chemical Engineering Composite Science and Engineering
Identifiers
urn:nbn:se:miun:diva-29336 (URN)10.1016/j.matlet.2016.10.026 (DOI)000390628200045 ()2-s2.0-84994876232 (Scopus ID)FSCN (Local ID)FSCN (Archive number)FSCN (OAI)
Projects
NovoCell - Novel use of native cellulose in dispersions and functional biocomposites
Funder
Swedish Research Council Formas, 942-2015-251
Available from: 2016-11-24 Created: 2016-11-24 Last updated: 2018-06-28Bibliographically approved
Eivazihollagh, A., Tejera, J., Svanedal, I., Edlund, H., Blanco, A. & Norgren, M. (2017). Removal of Cd2+, Zn2+, and Sr2+ by Ion Flotation, Using a Surface-Active Derivative of DTPA (C12-DTPA). Industrial & Engineering Chemistry Research, 56(38), 10605-10614
Open this publication in new window or tab >>Removal of Cd2+, Zn2+, and Sr2+ by Ion Flotation, Using a Surface-Active Derivative of DTPA (C12-DTPA)
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2017 (English)In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 56, no 38, p. 10605-10614Article in journal (Refereed) Published
Abstract [en]

Ion flotation was studied for the removal of cadmium, zinc, and strontium ions from aqueous solutions at pH 5–9 in a customized flotation cell, using an aminopolycarboxylic chelating surfactant, 2-dodecyldiethylenetriamine pentaacetic acid (C12-DTPA) in combination with two foaming agents: dodecyltrimethylammonium chloride (DoTAC) and dimethyldodecylamine-N-oxide (DDAO). The results from experiments showed that both Zn2+ and Cd2+ could be removed via ion flotation to 100% at pH 5, and Sr2+ could be removed via ion flotation to 60%–70% at pH 7–9. The removal of metal ions from the flotation cell was seen to vary with pH, but this was not exclusively related to the magnitudes of the formed metal ion-chelating surfactant conditional stability constants. The removal was also dependent on the foam properties of the samples that were found to vary over the investigated pH interval. The outcome of the investigation points to the chelating surfactant C12-DTPA having excellent chelating properties for all of the studied ions above pH 7. In combination with correctly chosen foaming agents, the optimized surfactant system could be expected to provide very efficient remediation of waters polluted with metal ions via ion flotation.

National Category
Engineering and Technology
Identifiers
urn:nbn:se:miun:diva-31643 (URN)10.1021/acs.iecr.7b03100 (DOI)000412043400007 ()2-s2.0-85030457973 (Scopus ID)
Available from: 2017-09-20 Created: 2017-09-20 Last updated: 2018-06-28Bibliographically approved
Lindman, B., Medronho, B., Alves, L., Costa, C., Edlund, H. & Norgren, M. (2017). The relevance of structural features of cellulose and its interactions to dissolution, regeneration, gelation and plasticization phenomena. Physical Chemistry, Chemical Physics - PCCP, 19(35), 23704-23718
Open this publication in new window or tab >>The relevance of structural features of cellulose and its interactions to dissolution, regeneration, gelation and plasticization phenomena
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2017 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, no 35, p. 23704-23718Article in journal (Refereed) Published
Abstract [en]

Cellulose is the most abundant polymer and a very important renewable resource. Since cellulose cannot be shaped by melting, a major route for its use for novel materials, new chemical compounds and renewable energy must go via the solution state. Investigations during several decades have led to the identification of several solvents of notably different character. The mechanisms of dissolution in terms of intermolecular interactions have been discussed from early work but, even on fundamental aspects, conflicting and opposite views appear. In view of this, strategies for developing new solvent systems for various applications have remained obscure. There is for example a strong need for using forest products for higher value materials and for environmental and cost reasons to use water-based solvents. Several new water-based solvents have been developed recently but there is no consensus regarding the underlying mechanisms. Here we wish to address the most important mechanisms described in the literature and confront them with experimental observations. A broadened view is helpful for improving the current picture and thus cellulose derivatives and phenomena such as fiber dissolution, swelling, regeneration, plasticization and dispersion are considered. In addition to the matter of hydrogen bonding versus hydrophobic interactions, the role of ionization as well as some applications of new knowledge gained are highlighted.

National Category
Physical Chemistry
Identifiers
urn:nbn:se:miun:diva-31407 (URN)10.1039/C7CP02409F (DOI)000410585900012 ()28621781 (PubMedID)2-s2.0-85029414642 (Scopus ID)
Projects
Cello
Funder
Swedish Research Council, 2015-04290VINNOVA, 2013-05617
Available from: 2017-08-16 Created: 2017-08-16 Last updated: 2017-12-18Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-3407-7973

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