| 1. |
- Jung, Christian, et al.
(författare)
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A comparison of very old patients admitted to intensive care unit after acute versus elective surgery or intervention
- 2019
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Ingår i: Journal of critical care. - : W B SAUNDERS CO-ELSEVIER INC. - 0883-9441 .- 1557-8615. ; 52, s. 141-148
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Tidskriftsartikel (refereegranskat)abstract
- Background: We aimed to evaluate differences in outcome between patients admitted to intensive care unit (ICU) after elective versus acute surgery in a multinational cohort of very old patients (80 years; VIP). Predictors of mortality, with special emphasis on frailty, were assessed.Methods: In total, 5063 VIPs were induded in this analysis, 922 were admitted after elective surgery or intervention, 4141 acutely, with 402 after acute surgery. Differences were calculated using Mann-Whitney-U test and Wilcoxon test. Univariate and multivariable logistic regression were used to assess associations with mortality.Results: Compared patients admitted after acute surgery, patients admitted after elective surgery suffered less often from frailty as defined as CFS (28% vs 46%; p < 0.001), evidenced lower SOFA scores (4 +/- 5 vs 7 +/- 7; p < 0.001). Presence of frailty (CFS >4) was associated with significantly increased mortality both in elective surgery patients (7% vs 12%; p = 0.01), in acute surgery (7% vs 12%; p = 0.02).Conclusions: VIPs admitted to ICU after elective surgery evidenced favorable outcome over patients after acute surgery even after correction for relevant confounders. Frailty might be used to guide clinicians in risk stratification in both patients admitted after elective and acute surgery.
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| 2. |
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| 3. |
- Frykstrand, Sara, et al.
(författare)
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Synthesis, electron microscopy and X-ray characterization of oxymagnesite, MgO∙2MgCO3, formed from amorphous magnesium carbonate
- 2014
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Ingår i: CrystEngComm. - : Royal Society of Chemistry (RSC). - 1466-8033. ; 16:47, s. 10837-10844
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Tidskriftsartikel (refereegranskat)abstract
- At present, the peculiar compound called oxymagnesite, MgO center dot 2MgCO(3), an intermediate formed during thermal decomposition of hydrated magnesium carbonates, has only been described a handful of times without a distinct description of its formation or morphology. In the current work we present the first scanning and transmission electron microscopy images of an oxymagnesite crystal together with its crystallographic data. Oxymagnesite was synthesized in a controlled manner via decomposition of amorphous magnesium carbonates (AMCs) subjected to varying relative humidity. We show that oxymagnesite is formed only when AMC is hydrated above a certain level, which we attribute to structural inequivalence between CO3 groups induced by water in AMC subjected to high humidity resulting in a weakening of some of the Mg-CO3 bonds. The study provides an understanding of the conditions needed for oxymagnesite formation and shows how hydrated AMCs can be used as precursors of different types of magnesium carbonates.
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| 4. |
- Karlsson, Christoffer, 1986-, et al.
(författare)
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Nonstoichiometric Triazolium Protic Ionic Liquids for All-Organic Batteries
- 2018
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Ingår i: ACS Applied Energy Materials. - : American Chemical Society. - 2574-0962. ; :11, s. 6451-6462
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Tidskriftsartikel (refereegranskat)abstract
- Nonstoichiometric protic ionic liquids (NSPILs) are efficient electrolytes for protic electrochemical devices such as the all-organic proton battery, which has been suggested as a sustainable approach to energy storage. NSPILs contain a mixture of proton donors and acceptors and are ideal for this purpose due to their high proton conductivity, high electrochemical stability, low cost, and ease of synthesis. However, the electrolyte proton activity must be controlled carefully in these devices since it greatly influences the kinetics and energetics of the electrode redox reactions and, hence, also impacts battery device performance. In this study, specific NSPILs were designed and evaluated as electrolytes for the all-organic proton battery. The NSPILs were based on either 1,2,4-triazole or 1-methyl-1,2,4-triazole partially protonated with bis(trifluoromethylsulfonyl)imide (TFSI) to produce a range of NSPILs with different degrees of protonation. Both types of NSPIL investigated here exhibited a maximum conductivity of 1.2 S/cm (at 120 and 70 °C, respectively), and the eutectic composition of 1-methyl-1,2,4-triazolium TFSI also had high conductivity at 25 °C (24.9 mS/cm), superior to, e.g., imidazolium TFSI NSPILs. Pulsed field gradient NMR in conjunction with electrochemical impedance spectroscopy showed that the conductivity originated mainly from vehicle diffusion and proton hopping. Quinone functionalized poly(3,4-ethylenedioxythiophene) (PEDOT) electrodes exhibited reversible, fast, and stable redox conversion in these electrolytes, and a model is suggested to determine proton activities of NSPILs based on the quinone formal potential. An all-organic proton battery cell was assembled to demonstrate the usefulness of these electrolytes in devices. Fast and complete redox conversion with a cell potential of 0.45 V was demonstrated, even up to scan rates corresponding to 140 C. Compared to the pyridine based electrolytes used for the all-organic proton battery up until now, the present electrolytes display several advantages including lower melting point, lower toxicity, and compatibility with plastic materials.
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| 5. |
- Oka, Kouki, et al.
(författare)
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Characterization of PEDOT-Quinone conducting redox polymers in water-in-salt electrolytes for safe and high-energy Li-ion batteries
- 2019
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Ingår i: Electrochemistry communications. - : Elsevier. - 1388-2481 .- 1873-1902. ; 105
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Tidskriftsartikel (refereegranskat)abstract
- Li-ion batteries (LIBs) raise safety and environmental concerns, which mostly arise from their toxic and flammable electrolytes and the extraction of limited material resources by mining. Recently, water-in-salt electrolytes (WiSEs), in which a large amount of lithium salt is dissolved in water, have been proposed to allow for assembling safe and high-voltage (>3.0 V) aqueous LIBs. In addition, organic materials derived from abundant building blocks and their tunable properties could provide safe and sustainable replacements for inorganic cathode materials. In the current work, the electrochemical properties of a conducting redox polymer based on poly(3,4-ethylenedioxythiophene) (PEDOT) with hydroquinone (HQ) pendant groups have been characterized in WiSEs. The quinone redox reaction occurs within the potential region where the polymer is conducting, and fast redox conversion that involves lithium cycling during pendant group redox conversion was observed. These properties make conducting redox polymers promising candidates as cathode-active materials for safe and high-energy aqueous LIBs. An organic-based aqueous LIB, with a HQ-PEDOT as a cathode, Li4Ti5O12 (LTO) as an anode, and ca. 15 m lithium bis(trifluoromethanesulfonyl)imide water/dimethyl carbonate (DMC) as electrolyte, yielded an output voltage of 1.35 V and high rate capabilities up to 500C.
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| 6. |
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| 7. |
- Sjödin, Martin, 1974-, et al.
(författare)
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Conducting redox oligomers
- 2022
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Patent (populärvet., debatt m.m.)abstract
- The present disclosure relates to compounds of formula IVa or IVb, or salts thereof, as intermediates in the manufacture of conducting redox polymers. L is a covalent linker moiety and R is a reversible redox group.The disclosure further relates to conducting redox polymers produced from such compounds, as well as substrates coated with such conducting redox polymers, and organic batteries comprising such conducting redox polymers.
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| 8. |
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| 9. |
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| 10. |
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| 11. |
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| 12. |
- Sjödin, Martin, 1974-, et al.
(författare)
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Conducting Redox Polymers as Electrical Energy Storage Materials
- 2019
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Konferensbidrag (refereegranskat)abstract
- Conducting redox polymers (CRPs) is an attractive alternative as organic matter based electrical energy storage materials as they provide means of combining the favorable charge transport properties of conducting polymers with the high capacity and well defined redox chemistry of small redox active groups. In general CRPs are composed of a conducting polymer backbone where each or some of the monomers building up the polymer is bearing a redox active functional group. Although the working principle of CRPs is straightforward several key criteria need to be met in the CRP design in order to benefit from synergetic effects of the conducting polymer backbone and the pendent group in CRPs that will be outlined in this presentation: 1) As conducting polymers are only conducting in their charged state successful polymer-pendent group combinations rely on that the pendant group has a redox potential within the conducting region of the polymer backbone. This condition is referred to as redox matching and the requirement in the CRP design will be explicitly proven.[1] 2) The purpose of the polymer backbone is to provide efficient electron transport through the material. We have previously shown the polymer conductivity can be severely compromised by the pendant group.[2] This could be overcome by judicious choice of polymer backbone and results will be presented that show that non-activated (semi-metallic) electron transport can be achieved in CRPs.[3-4] 3) A final design principle that will be discussed is related to the polymerizability and how it is affected by the nature of the link between the polymer backbone and the pendent.[5] In addition a novel polymerization method for CRP monomers will be presented that allow bulk processing even for insoluble CRPmaterials.
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| 13. |
- Sjödin, Martin, 1974-, et al.
(författare)
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Designing Quinone-based Conducting Redox Polymers specifically for Aqueous Proton Batteries and for Lithium Ion Battery Cathodes
- 2020
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Konferensbidrag (refereegranskat)abstract
- Conducting redox polymers (CRPs) are conducting polymers that have been decorated with redox active functional groups and they provide an attractive alternative as organic matter based electrical energy storage materials. The purpose of the polymer backbone is two-fold, 1) it prevents dissolution of the redox group and, 2) it renders the material conductive. The redox active pendant groups, on the other hand, provide the material with a well-defined redox reaction as well as a high charge storage capacity. CRPs thus provide a solution to two of the most significant obstacles in achieving powerful and stable battery materials from organic compounds, i.e. materials dissolution and limited electronic conductivity while simultaneously providing a high charge storage capacity. For battery applications it is thus essential that the individual properties of the conducting polymer backbone and the redox group can be preserved and that they operate in synergy in the CRP. One prerequisite for synergetic polymer-pendant combinations is redox matching. As conducting polymers are only conducting in their charged state successful combinations rely on that the pendant group has a redox potential within the conducting region of the polymer backbone. In addition, the CRP must allow mass transport of ions, not only related to the cycling chemistry of the pendant group but also ions related to the doping of the polymer backbone. These requirements put significantly different demands on the polymer design for the development of aqueous proton batteries and for CRPs for lithium cycling cathodes. In this presentation specific CRP design-solutions will be presented that allow for the development of all-organic proton batteries 1,2 and for lithium ion CRP-battery cathodes 3. In addition, a solution-processing method, termed Post Deposition Polymerization (PDP), for CRP-materials and the underlying principles and requirements for PDP will be presented. Importantly, in PDP the processing step occurs prior to polymerization. After depositing and drying of the repeat-unit precursor onto a substrate polymerization is achieved by oxidative polymerization of the precursor. The PDP-method opens up for a scalable method for the coating of CRP materials onto any substrate and can, for instance, be used to make nanostructured CRP materials.1 Emanuelsson, R., Sterby, M., Strømme, M. & Sjödin, M. An All-Organic Proton Battery. J. Am. Chem. Soc. 139, 4828-4834, doi:10.1021/jacs.7b00159 (2017).2 Strietzel, C. et al. Accepted in Angewandte Chemie doi:10.1002/anie.202001191 (2020).3 Wang, H. et al. Redox-State-Dependent Interplay between Pendant Group and Conducting Polymer Backbone in Quinone-Based Conducting Redox Polymers for Lithium Ion Batteries. ACS Applied Energy Materials 2, 7162-7170, doi:10.1021/acsaem.9b01130 (2019).
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| 14. |
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| 15. |
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| 16. |
- Sterby, Mia, 1989-, et al.
(författare)
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Post-Deposition Polymerization : A Method for Circumventing Processing of Insoluble Conducting Polymers
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Annan publikation (populärvet., debatt m.m.)abstract
- A method, termed post-deposition polymerization, for the synthesis of conducting polymers is presented, which enables solid state polymerization of oligomeric layers by oxidative polymerization. The method was developed as a general tool for the preparation of conducting polymer layers that allows for industrially viable solution-processing methods to be used for substrate coating. We use trimer building blocks based on 3,4-ethylenedioxythiophene (EDOT) in the processing step, and show that the resulting trimer layer has innate conductivity when oxidized, which presumably is instrumental for successful polymerization of the solid layer. As judged by in situ conductance measurement during oxidative polymerization of the trimer layer, the layer-conductivity is greatly increased as a result of polymerization. Successful solid state polymerization was also confirmed by the irreversible spectral changes, monitored in-situ during polymerization, resulting in signature spectral transitions of conducting polymers from an initial spectrum derived solely from trimer absorption. From the in situ determined mass changes we estimate the swelling during post-deposition polymerization as well as the average polymer length. Electrochemical characterization of the resulting polymer show fast redox conversion as well as non-activated electron transport through the material indicating that the post-deposition polymerization-generated polymer indeed show promising properties. We believe that the post-deposition polymerization method will enable investigations, currently hampered by limited processability, of interesting families of conducting polymer materials.
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| 17. |
- Strietzel, Christian, et al.
(författare)
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An Alternative to Carbon Additives : The Fabrication of Conductive Layers Enabled by Soluble Conducting Polymer Precursors – A Case Study for Organic Batteries
- 2021
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Ingår i: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 13:4, s. 5349-5356
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Tidskriftsartikel (refereegranskat)abstract
- Utilizing organic redox-active materials as electrodes is a promising strategy to enable innovative battery designs with low environmental footprint during production, which can be hard to achieve with traditional inorganic materials. Most electrode compositions, organic or inorganic, require binders for adhesion and conducting additives to enable charge transfer through the electrode, in addition to the redox-active material. Depending on the redox-active material, many types and combinations of binders and conducting additives have been considered. We designed a conducting polymer (CP), with a soluble, trimeric unit based on 3,4-ethylenedioxythiophene (E) and 3,4-propylenedioxythiophene (P) as the repeat unit, acting as a combined binder and conducting additive. While CPs as additives have been explored earlier, in the current work, the use of a trimeric precursor enables solution processing together with the organic redox-active material. To evaluate this concept, the CP was blended with a redox polymer (RP), which contained a naphthoquinone (NQ) redox group at different ratios. The highest capacity for the total weight of the CP/RP electrode was 77 mAh/g at 1 C in the case of 30% EPE and 70% naphthoquinone-substituted poly(allylamine) (PNQ), which is 70% of the theoretical capacity given by the RP in the electrode. We further used this electrode in an aqueous battery, with a MnSO4 cathode. The battery displayed a voltage of 0.95 V, retaining 93% of the initial capacity even after 500 cycles at 1 C. The strategy of using a solution-processable CP precursor opens up for new organic battery designs and facile evaluation of RPs in such.
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| 18. |
- Strietzel, Christian, et al.
(författare)
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An Aqueous Conducting Redox-Polymer-Based Proton Battery that Can Withstand Rapid Constant-Voltage Charging and Sub-Zero Temperatures
- 2020
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Ingår i: Angewandte Chemie International Edition. - : Wiley. - 1433-7851 .- 1521-3773. ; 59:24, s. 9631-9638
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Tidskriftsartikel (refereegranskat)abstract
- Electrodes based on organic matter operating in aqueous electrolytes enable new approaches and technologies for assembling and utilizing batteries that are difficult to achieve with traditional electrode materials. Here, we report how thiophene‐based trimeric structures with naphthoquinone or hydroquinone redox‐active pendent groups can be processed in solution, deposited, dried and subsequently polymerized in solid state to form conductive (redox) polymer layers without any additives. Such post‐deposition polymerization offers efficient use of material, high mass loading (up to 10 mg cm−2) and good flexibility in the choice of substrate and coating method. By employing these materials as anode and cathode in an acidic aqueous electrolyte a rocking‐chair proton battery is built. The battery shows good cycling stability (85 % after 500 cycles), withstands rapid charging, with full capacity (60 mAh g−1) reached within 100 seconds, allows for direct integration with photovoltaics, and retains its favorable characteristics even at −24 °C.
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| 19. |
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| 20. |
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| 21. |
- Strietzel, Christian, et al.
(författare)
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Conducting Redox Polymer Batteries – Challenges and possibilities
- 2017
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Konferensbidrag (refereegranskat)abstract
- Apart from conventional metal based batteries, batteries consisting of naturally occurring organic materials can be envisioned, thus becoming fully sustainable and avoiding the negative environmental impact associated with the production and recycling of conventional metal based batteries. This way the negative environmental impact of the constantly increasing demand for secondary batteries is decreased. One class of fully organic batteries utilizes conducting redox polymers (CRPs) as electrode materials. CRPs combine the high charge storage capacity of a redox active pendant group (PG) with the conduction properties of a conducting polymer (CP) backbone, both to reduce the need for addition of conductive carbon black and increasing the stability of the PG redox conversion in a battery setup. In the current work, challenges and possibilities of this type of battery are discussed and a concept and initial results for a metal-free, fully organic battery based on CRP electrode materials is presented.
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| 22. |
- Strietzel, Christian, 1989-
(författare)
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Designing Quinone-based Organic Batteries
- 2021
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The demand for secondary energy storage is ever increasing, being at the forefront of the transformation to a sustainable society. Conventional batteries, whose electrode materials require mining and high temperature refining, generate substantial carbon dioxide emissions during production. Furthermore, the process for recycling of these batteries is difficult and still at in its infancy. On the contrary, organic batteries could be a sustainable and alternative energy storage solution and is therefore gaining increased attention. While there are several promising organic battery concepts, the focus in of this thesis has been towards batteries using quinones as capacity carrying units. Furthermore, a special emphasis was put on conducting polymers for providing conductivity within the electrode material, predominately in the form of conducting redox polymers. Several battery designs have been explored. All-organic batteries, cycling protons both with an ionic liquid and with a readily available aqueous electrolyte, have been evaluated with promising results concerning rate capabilities and low temperature operation. Hybrid-organic battery designs have shown that quinones easily cycle Lithium ions and act in a dual ion battery with a Manganese oxide cathode. This thesis therefore gives a broad overview on how quinone organic batteries can be designed and provides an outlook on how future development can be focused.
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| 23. |
- Strietzel, Christian, et al.
(författare)
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Flexible All Organic Batteries Based on Conducting Redox Polymers
- 2018
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Ingår i: MRS Fall meeting 2018. - Boston.
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Konferensbidrag (refereegranskat)abstract
- Batteries consisting of naturally occurring organic materials can be envisioned as sustainable alternatives to conventional metal-based batteries, thusavoiding the negative environmental impact associated with the production and recycling of the latter. In this way the negative environmental impact of theconstantly increasing demand for secondary batteries can be decreased. Apart from being fully organic, such batteries also open up for flexible batterydesigns as they can be produced in a roll-to-roll process and they are anticipated to be viable in a broad range of applications as energy supplies ininnovative flexible electronics designs. In the current work, fully organic batteries are realized utilizing conducting redox polymers (CRPs) as electrodematerials. CRPs combine the high charge storage capacity of a redox active pendant group (PG) with the conduction properties of a conducting polymer(CP) backbone, both to reduce the need for addition of conductive carbon black and increasing the stability of the PG redox conversion in a battery setup.The first results from a fully organic, aqueous battery based on CRP electrode material are presented. Challenges and possibilities of this type of battery in flexible battery designs are discussed.
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| 24. |
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