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Edvinsson, Tomas, ProfessorORCID iD iconorcid.org/0000-0003-2759-7356
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Publications (10 of 117) Show all publications
Edvinsson, T. (2019). A concentrated effort. NATURE ENERGY, 4(5), 354-355
Open this publication in new window or tab >>A concentrated effort
2019 (English)In: NATURE ENERGY, ISSN 2058-7546, Vol. 4, no 5, p. 354-355Article in journal, Editorial material (Other academic) Published
Abstract [en]

While recent gains in the efficiency of photoelectrochemical devices for hydrogen production are encouraging, high efficiency is rarely combined with high power output, which is important for large-scale viability. Towards this goal, researchers now demonstrate a promising thermally integrated device driven by concentrated solar irradiation.

National Category
Energy Engineering Condensed Matter Physics
Identifiers
urn:nbn:se:uu:diva-385784 (URN)10.1038/s41560-019-0381-7 (DOI)000467965700006 ()
Available from: 2019-06-17 Created: 2019-06-17 Last updated: 2019-06-17Bibliographically approved
Edvinsson, T. & Hagfeldt, A. (Eds.). (2019). Characterization Techniques for Perovskite Solar Cell Materials (1ed.). Elsevier
Open this publication in new window or tab >>Characterization Techniques for Perovskite Solar Cell Materials
2019 (English)Collection (editor) (Refereed)
Place, publisher, year, edition, pages
Elsevier, 2019. p. 274 Edition: 1
Series
Micro and Nano Technologies
National Category
Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-400946 (URN)012814727X (ISBN)
Available from: 2020-01-03 Created: 2020-01-03 Last updated: 2020-01-08
Michaels, H., Benesperi, I., Edvinsson, T., Munoz-Garcia, A. B., Pavone, M., Boschloo, G. & Freitag, M. (2019). Correction: Michaels, H.; et al. Copper Complexes with Tetradentate Ligands for Enhanced Charge Transport in Dye-Sensitized Solar Cells. Inorganics 2018, 6, 53. Inorganics, 7(11), Article ID 130.
Open this publication in new window or tab >>Correction: Michaels, H.; et al. Copper Complexes with Tetradentate Ligands for Enhanced Charge Transport in Dye-Sensitized Solar Cells. Inorganics 2018, 6, 53
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2019 (English)In: Inorganics, ISSN 2304-6740, Vol. 7, no 11, article id 130Article in journal (Refereed) Published
National Category
Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-400431 (URN)10.3390/inorganics7110130 (DOI)000500003800001 ()
Note

Correction for: Inorganics, vol. 6, issue 2, article number: 53.

Available from: 2019-12-20 Created: 2019-12-20 Last updated: 2019-12-20Bibliographically approved
Qiu, Z. & Edvinsson, T. (2019). Direct observation of active catalyst redox states and the effect of dynamically increased crystallinity on efficient alkaline water splitting. In: : . Paper presented at spring 2019 ACS National Meeting & Exposition.
Open this publication in new window or tab >>Direct observation of active catalyst redox states and the effect of dynamically increased crystallinity on efficient alkaline water splitting
2019 (English)Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

Given the global increase in energy demand and serious environmental pollution, hydrogen fuel is a promising energy carrier to replace traditional fossil fuels due to its zero gas emissions and high energy density by weight. Electrochemical water electrolysis with non-precious metal catalysts offers a simple and cost-effective way for high purity and large-scale hydrogen generation. The realization of hydrogen evolution, however, is hampered by the large sustainable driving potential needed above the thermodynamic requirements. Here, we report dynamically crystallinity-enhanced (DCE) NiFe layered double hydroxide (LDH) ultrathin nanosheets, leading to faster electron transfer, smooth gas release ability, and more active surface areas, resulting in markedly improved catalytic efficiency. Compared with untreated NiFe LDH, DCE NiFe LDH exhibits much lower overpotential for the cathode reaction. Under 1 M KOH aqueous electrolyte, the bi-functional DCE catalysts require only 1.48 V and 1.29 V to reach 10 and 1 mA cm-2 in two-electrode measurements without iR-compensation, corresponding to 83% and 95% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. In-situ Raman spectro-electrochemistry was carried out to obtain insight into the active catalyst phases, revealing the role of Fe and Ni and their function for OER and HER, respectively. The transformation from Ni(OH)2 to γ-NiOOH was clearly observed by in-situ Raman spectroscopy under OER operation. While, the Raman features of Ni(OH)2 and FeOOH were shown under HER process. It means the function of Ni and Fe is different under OER and HER, but it is noticeable that the observed Ni and Fe species at the different applied overpotential are dominant contribution to the catalytic activity. Our results shed light on the full understanding of overall water splitting in NiFe LDH ultrathin nanosheets and developing more efficient catalysts.

National Category
Engineering and Technology Natural Sciences
Identifiers
urn:nbn:se:uu:diva-398149 (URN)
Conference
spring 2019 ACS National Meeting & Exposition
Available from: 2019-12-02 Created: 2019-12-02 Last updated: 2019-12-02
Qiu, Z., Tai, C.-W., Niklasson, G. & Edvinsson, T. (2019). Direct observation of active catalyst surface phases and the effect of dynamic self-optimization in NiFe-layered double hydroxides for alkaline water splitting. Energy & Environmental Science, 12(2), 572-581
Open this publication in new window or tab >>Direct observation of active catalyst surface phases and the effect of dynamic self-optimization in NiFe-layered double hydroxides for alkaline water splitting
2019 (English)In: Energy & Environmental Science, ISSN 1754-5692, E-ISSN 1754-5706, Vol. 12, no 2, p. 572-581Article in journal (Refereed) Published
Abstract [en]

Earth-abundant transition metal-based compounds are of high interest as catalysts for sustainable hydrogen fuel generation. The realization of effective electrolysis of water, however, is still limited by the requirement of a high sustainable driving potential above thermodynamic requirements. Here, we report dynamically self-optimized (DSO) NiFe layered double hydroxide (LDH) nanosheets with promising bi-functional performance. Compared with pristine NiFe LDH, DSO NiFe LDH exhibits much lower overpotential for the hydrogen evolution reaction (HER), even outperforming platinum. Under 1 M KOH aqueous electrolyte, the bi-functional DSO catalysts show an overpotential of 184 and -59 mV without iR compensation for oxygen evolution reaction (OER) and HER at 10 mA cm(-2). The material system operates at 1.48 V and 1.29 V to reach 10 and 1 mA cm(-2) in two-electrode measurements, corresponding to 83% and 95% electricity-to-fuel conversion efficiency with respect to the lower heating value of hydrogen. The material is seen to dynamically reform the active phase of the surface layer during HER and OER, where the pristine and activated catalysts are analyzed with ex situ XPS, SAED and EELS as well as with in situ Raman spectro-electrochemistry. The results show transformation into different active interfacial species during OER and HER, revealing a synergistic interplay between iron and nickel in facilitating water electrolysis.

Place, publisher, year, edition, pages
ROYAL SOC CHEMISTRY, 2019
National Category
Other Chemical Engineering
Identifiers
urn:nbn:se:uu:diva-379268 (URN)10.1039/c8ee03282c (DOI)000459741700005 ()
Funder
Swedish Energy AgencySwedish Research Council, VR-2016-03713Swedish Research Council Formas, 2016-00908Knut and Alice Wallenberg Foundation
Available from: 2019-03-18 Created: 2019-03-18 Last updated: 2019-03-29Bibliographically approved
Grånäs, O., Timneanu, N., Eliah Dawod, I., Ragazzon, D., Trygg, S., Souvatzis, P., . . . Caleman, C. (2019). Femtosecond bond breaking and charge dynamics in ultracharged amino acids. Journal of Chemical Physics, 151(14), Article ID 144307.
Open this publication in new window or tab >>Femtosecond bond breaking and charge dynamics in ultracharged amino acids
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2019 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 151, no 14, article id 144307Article in journal (Refereed) Published
Abstract [en]

Historically, structure determination of nanocrystals, proteins, and macromolecules required the growth of high-quality crystals sufficiently large to diffract X-rays efficiently while withstanding radiation damage. The development of the X-ray free-electron laser has opened the path toward high resolution single particle imaging, and the extreme intensity of the X-rays ensures that enough diffraction statistics are collected before the sample is destroyed by radiation damage. Still, recovery of the structure is a challenge, in part due to the partial fragmentation of the sample during the diffraction event. In this study, we use first-principles based methods to study the impact of radiation induced ionization of six amino acids on the reconstruction process. In particular, we study the fragmentation and charge rearrangement to elucidate the time scales involved and the characteristic fragments occurring.

National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:uu:diva-395440 (URN)10.1063/1.5116814 (DOI)000500356200030 ()31615216 (PubMedID)
Funder
Swedish National Infrastructure for Computing (SNIC), SNIC 2019/8-30Swedish National Infrastructure for Computing (SNIC), SNIC 2018/3-221Swedish Research Council, 637-2013-7303Swedish Research Council, 2013-3940Swedish Foundation for Strategic Research , ICA16-0037
Available from: 2019-10-18 Created: 2019-10-18 Last updated: 2020-01-13Bibliographically approved
Jain, S. M., Edvinsson, T. & Durrant, J. R. (2019). Green fabrication of stable lead-free bismuth based perovskite solar cells using a non-toxic solvent. COMMUNICATIONS CHEMISTRY, 2, Article ID 91.
Open this publication in new window or tab >>Green fabrication of stable lead-free bismuth based perovskite solar cells using a non-toxic solvent
2019 (English)In: COMMUNICATIONS CHEMISTRY, ISSN 2399-3669, Vol. 2, article id 91Article in journal (Refereed) Published
Abstract [en]

The very fast evolution in certified efficiency of lead-halide organic-inorganic perovskite solar cells to 24.2%, on par and even surpassing the record for polycrystalline silicon solar cells (22.3%), bears the promise of a new era in photovoltaics and revitalisation of thin film solar cell technologies. However, the presence of toxic lead and particularly toxic solvents during the fabrication process makes large-scale manufacturing of perovskite solar cells challenging due to legislation and environment issues. For lead-free alternatives, non-toxic tin, antimony and bismuth based solar cells still rely on up-scalable fabrication processes that employ toxic solvents. Here we employ non-toxic methyl-acetate solution processed (CH3NH3)(3)Bi2I9 films to fabricate lead-free, bismuth based (CH3NH3)(3)Bi2I9 perovskites on mesoporous TiO2 architecture using a sustainable route. Optoelectronic characterization, X-ray diffraction and electron microscopy show that the route can provide homogeneous and good quality (CH3NH3)(3)Bi2I9 films. Fine-tuning the perovskite/hole transport layer interface by the use of conventional 2,2',7,7'-tetrakis (N,N'-di-p-methoxyphenylamino)-9,9'-spirbiuorene, known as Spiro-OMeTAD, and poly(3-hexylthiophene-2,5-diyl - P3HT as hole transporting materials, yields power conversion efficiencies of 1.12% and 1.62% under 1 sun illumination. Devices prepared using poly(3-hexylthiophene-2,5-diyl hole transport layer shown 300 h of stability under continuous 1 sun illumination, without the use of an ultra violet-filter.

Place, publisher, year, edition, pages
NATURE PUBLISHING GROUP, 2019
National Category
Materials Chemistry Physical Chemistry
Identifiers
urn:nbn:se:uu:diva-393334 (URN)10.1038/s42004-019-0195-3 (DOI)000479257900001 ()
Funder
EU, Horizon 2020, 663830
Available from: 2019-09-27 Created: 2019-09-27 Last updated: 2019-09-27Bibliographically approved
Bayrak Pehlivan, I., Arvizu, M. A., Qiu, Z., Niklasson, G. A. & Edvinsson, T. (2019). Impedance Spectroscopy Modeling of Nickel–Molybdenum Alloys on Porous and Flat Substrates for Applications in Water Splitting. The Journal of Physical Chemistry C, 123(39), 23890-23897
Open this publication in new window or tab >>Impedance Spectroscopy Modeling of Nickel–Molybdenum Alloys on Porous and Flat Substrates for Applications in Water Splitting
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2019 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 123, no 39, p. 23890-23897Article in journal (Refereed) Published
Abstract [en]

Hydrogen production by splitting water using electrocatalysts powered by renewable energy from solar or wind plants is one promising alternative to produce a carbon-free and sustainable fuel. Earth-abundant and nonprecious metals are, here, of interest as a replacement for scarce and expensive platinum group catalysts. Ni–Mo is a promising alternative to Pt, but the type of the substrate could ultimately affect both the initial growth conditions and the final charge transfer in the system as a whole with resistive junctions formed in the heterojunction interface. In this study, we investigated the effect of different substrates on the hydrogen evolution reaction (HER) of Ni–Mo electrocatalysts. Ni–Mo catalysts (30 atom % Ni, 70 atom % Mo) were sputtered on various substrates with different porosities and conductivities. There was no apparent morphological difference at the surface of the catalytic films sputtered on the different substrates, and the substrates were classified from microporous to flat. The electrochemical characterization was carried out with linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS) in the frequency range 0.7 Hz–100 kHz. LSV measurements were carried out at direct current (DC) potentials between 200 and −400 mV vs the reversible hydrogen electrode (RHE) in 1 M NaOH encompassing the HER. The lowest overpotentials for HER were obtained for films on the nickel foam at all current densities (−157 mV vs RHE @ 10 mA cm–2), and the overpotentials increased in the order of nickel foil, carbon cloth, fluorine-doped tin oxide, and indium tin oxide glass. EIS data were fitted with two equivalent circuit models and compared for different DC potentials and different substrate morphologies and conductivities. By critical evaluation of the data from the models, the influence of the substrates on the reaction kinetics was analyzed in the high- and low-frequency regions. In the high-frequency region, a strong substrate dependence was seen and interpreted with a Schottky-type barrier, which can be rationalized as being due to a potential barrier in the material heterojunctions or a resistive substrate–film oxide/hydroxide. The results highlight the importance of substrates, the total charge transfer properties in electrocatalysis, and the relevance of different circuit components in EIS and underpin the necessity to incorporate high-conductivity, chemically inert, and work-function-matched substrate–catalysts in the catalyst system.

Place, publisher, year, edition, pages
American Chemical Society (ACS), 2019
National Category
Materials Chemistry
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-395176 (URN)10.1021/acs.jpcc.9b02714 (DOI)000489086300017 ()
Funder
EU, Horizon 2020Swedish Research Council, VR-2015-03814Swedish Research Council, VR-2016-03713
Available from: 2019-10-14 Created: 2019-10-14 Last updated: 2019-12-12Bibliographically approved
Niklasson, G., Qiu, Z., Bayrak Pehlivan, I. & Edvinsson, T. (2019). Impedance spectroscopy of water splitting reactions on nanostructured metal-based catalysts. In: Functional Materials and Nanotechnologies (FM&NT 2018): . Paper presented at 12th International Scientific Conference on Functional Materials and Nanotechnologies (FM&NT), OCT 02-05, 2018, Riga, Latvia. Institute of Physics Publishing (IOPP), Article ID 012005.
Open this publication in new window or tab >>Impedance spectroscopy of water splitting reactions on nanostructured metal-based catalysts
2019 (English)In: Functional Materials and Nanotechnologies (FM&NT 2018), Institute of Physics Publishing (IOPP), 2019, article id 012005Conference paper, Oral presentation with published abstract (Refereed)
Abstract [en]

Hydrogen production by water splitting using nanomaterials as electrocatalysts is a promising route enabling replacement of fossil fuels by renewable energy sources. In particular, the development of inexpensive non-noble metal-based catalysts is necessary in order to replace currently used expensive Pt-based catalysts. We report a detailed impedance spectroscopy study of Ni-Mo and Ni-Fe based electrocatalytic materials deposited onto porous and compact substrates with different conductivities. The results were interpreted by a critical comparison with equivalent circuit models. The reaction resistance displays a strong dependence on potential and a lower substrate dependence. The impedance behaviour can also provide information on the dominating reaction mechanism. An optimized Ni-Fe based catalyst showed very promising properties for applications in water electrolysis.

Place, publisher, year, edition, pages
Institute of Physics Publishing (IOPP), 2019
Series
IOP Conference Series-Materials Science and Engineering, ISSN 1757-8981 ; 503:1
National Category
Engineering and Technology Physical Chemistry
Research subject
Engineering Science with specialization in Solid State Physics
Identifiers
urn:nbn:se:uu:diva-369729 (URN)10.1088/1757-899X/503/1/012005 (DOI)000471150800005 ()
Conference
12th International Scientific Conference on Functional Materials and Nanotechnologies (FM&NT), OCT 02-05, 2018, Riga, Latvia
Funder
Swedish Research Council, VR-2016-03713Swedish Research Council, VR-2015-03814EU, Horizon 2020
Available from: 2018-12-17 Created: 2018-12-17 Last updated: 2020-01-08Bibliographically approved
Qiu, Z., Ma, Y. & Edvinsson, T. (2019). In operando Raman investigation of Fe doping influence on catalytic NiO intermediates for enhanced overall water splitting. Nano Energy, 66, Article ID 104118.
Open this publication in new window or tab >>In operando Raman investigation of Fe doping influence on catalytic NiO intermediates for enhanced overall water splitting
2019 (English)In: Nano Energy, ISSN 2211-2855, E-ISSN 2211-3282, Vol. 66, article id 104118Article in journal, Editorial material (Refereed) Published
Abstract [en]

Transition metal iron (Fe)-incorporated Ni oxide and oxyhydroxide compounds generally show an enhanced activity for alkaline water splitting. However, the role of Fe for this enhanced activity is not fully elucidated, especially under hydrogen evolution reaction (HER). Herein, we combine electrochemical and spectroscopic techniques to investigate the Fe doping effect on self-standing NiO nanosheets for enhanced activities for both HER and oxygen evolution reaction (OER) in overall water splitting. The results show that the presence of Fe suppresses Ni self-oxidation and adjusts the Ni–O local environment and its ability to form surface phases. In operando Raman spectroscopy is utilized to explore the active intermediates present under catalytic conditions. Apart from a slight suppression of grain size, our results show that Fe incorporation into NiO enhances in-situ formation of active layered intermediates NixFe1-xOOH with a phase transformation of FeOOH layers into γ-NiOOH layers containing Ni4+ at potentials approaching OER in contrast to undoped NiO electrodes with a dominating conversion of NiO to β-NiOOH, with persisting Ni3+. In addition, the work function on the electrode surface is reduced by 90 meV upon Fe doping, revealing a higher intrinsic Fermi-level and thus a lower requirement for added bias during HER. Together with the lower resistance for electron transport beneficial for both HER and OER, this leads to improved OER and HER efficiency upon Fe-doping. The study shows how Fe doping influences the active catalytic NiO intermediates for both HER and OER. Specifically, in operando vibrational spectroscopy utilized in parallel with electrochemical characterization can shed light on enhancement mechanisms and influence of doping for catalytic intermediates under any chosen bias at the respective electrode under full water splitting.

National Category
Other Materials Engineering
Identifiers
urn:nbn:se:uu:diva-398147 (URN)10.1016/j.nanoen.2019.104118 (DOI)000503062400038 ()
Funder
Swedish Energy AgencySwedish Research Council, 2016-00908Swedish Research Council, VR 2015-03814
Available from: 2019-12-02 Created: 2019-12-02 Last updated: 2020-01-22Bibliographically approved
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ORCID iD: ORCID iD iconorcid.org/0000-0003-2759-7356

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