First virtual Bilateral Conference on Functional Materials (BiC-FM). Сборник статей
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Название: First virtual Bilateral Conference on Functional Materials (BiC-FM)
Автор: Сборник статей
Издательство: Aegitas
Жанр: Техническая литература
isbn: 9780369404497
isbn:
2017–2016 Head of Laboratory of Materials and Chemical Analysis
2017–2019 Head of Department
Honors or Awards
1996 The Alftan prize for meritorious thesis published awarded by The Finnish Chemists Society
1996 The Elvings prize for the best thesis published at the Åbo Akademi University
1997 Representative for Finland at Scientia Europea 2. Organized by Académie des Sciences (French Academy of Sciences) France.
2006 The Pehr Brahe prize for meritorious research work awarded by the Foundation of Åbo Akademi University.
2020 Member of Finnish Academy of Science and Letters
Research Interests
Conjugated polymers, composite materials, graphene and graphene oxide, ionic liquids, CO2 conversion, in situ spectroelectrochemistry, electrochemistry
Publications; 137 peer reviewed international scientific journals, 3 patent applications
Positronium emission from materials for Li-ion batteries
Bernardo Barbiellini1,2*, Jan Kuriplach3
1School of Engineering Science, LUT university, Lappeenranta 53851, Finland
2Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA
3Department of Low Temperature Physics, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, CZ-180 00 Prague, Czech Republic
A positron and an electron annihilate into gamma-ray photons but before this annihilation, the positron and an electron can bind together to form a positronium (Ps). Mono-energetic positron beams can be used to bombard materials and to probe their atomistic properties. In particular, the implanted positron can diffuse back to the surface of a solid and be emitted as Ps with a range of kinetic energies that provides key information regarding the energy levels of the electrons in the material. These energies can be measured by time of flight (TOF) experiments, but the Ps lifetime before annihilation has been too short for precise measurements. Recently, Jones et al. [1], by exciting the emitted Ps with a laser to greatly increase its lifetime, obtained TOF measurements with an ultimate precision of the order of 5 meV that will allow materials simulations in systems pertinent for Li-ion batteries cathodes [2,3].
References:
[1] A. C. L. Jones, H. J. Rutbeck-Goldman, T. H. Hisakado, A. M. Piñeiro, H. W. K. Tom, A. P. Mills, Jr. B. Barbiellini, J. Kuriplach, Phys. Rev. Lett. 117, 216402 (2016)
[2] B. Barbiellini, J. Kuriplach, Journal of Physics: Conf. Series 791, 012016 (2017)
[3] J. Kuriplach, A. Pulkkinen, B. Barbiellini, Condensed Matter 4, 80 (2019)
The role of nitrogen and oxygen in the formation capacity of carbon materials
Evlashin S.A.1,*, Fedorov F.S.1, Dyakonov P.V. 1,2, Maksimov Yu.M.2, Pilevsky A.A.2, Maslakov K.I.2, Akhatov I.Sh.1
1 – Skolkovo Institute of Science and Technology, Moscow, Russia
2 – Lomonosov Moscow State University, Moscow, Russia
Carbon materials are attracting increasing attention as a material for supercapcitor fabrication due to availability and high specific surface area. However, the initial capacitance of raw carbon is quite low, so the N and O heteroatoms are introduced in order to increase their specific capacitance. Despite the vast amount of studies on carbon materials, a lot of grey areas in mechanisms that lead to the increase in the specific capacitance remain. We demonstrate an effective method for modification of the surface of Carbon NanoWalls (CNWs) using DC plasma in atmospheres of O2, N2, and their mixture. Processing in the plasma leads to the incorporation of ∼4 atom % nitrogen and ∼10 atom % oxygen atoms. Electrochemical measurements reveal that CNWs functionalized with oxygen groups are characterized by higher capacitance. The specific capacitance for samples with oxygen reaches 8.9 F cm-3 at a scan rate of 20 mV s-1. In contrast, the nitrogen-doped samples demonstrate a specific capacitance of 4.4 F cm-3 at the same scan rate. The mechanism of heteroatom incorporation into the carbon lattice is explained using density functional theory calculations.
Acknowledgement.This work was supported by the Russian Science Foundation, grant 17-19-01787.
References:
[1] S.A. Evlashin, F.S. Fedorov, P.V. Dyakonov, Y.M. Maksimov, A.A. Pilevsky, K.I. Maslakov, Y.O. Kuzminova, Y.A. Mankelevich, E.N. Voronina, S.A. Dagesyan, V.A. Pletneva, A.A. Pavlov, M.A. Tarkhov, I.V. Trofimov, V.L. Zhdanov, N.V. Suetin, I.S. Akhatov, I. S., Role of Nitrogen and Oxygen in Capacitance Formation of Carbon Nanowalls. The Journal of Physical Chemistry Letters, 11(12), (2020).
Nickel-Nitrogen active sites towards selective High-rate CO2-to-formate electroreduction
Cristina Flox1, Fatemeh Davodi1, Davide Pavesi2,3 and Tanja Kallio1
1 – Department of Chemistry and Materials Science, School of Chemical Engineering, Aalto University, FI-00076, Espoo, Finland
2 – Avantium Chemicals BV, Zekeringstraat 29 1014 BV Amsterdam, The Netherlands
3 – Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA, Leiden, The Netherlands
Electrochemical CO2 reduction reaction is a key technology for the mitigation of the climate change. However, CO2 reduction is highly energetic and unfavourable electrochemical reaction, requiring catalyst to achieve economically appealing performance. In this scenario, Nickel-Nitrogen (Ni-N)-active sites within porous carbon are attracting increasing interest as inexpensive and efficient electrocatalyst of CO2 reduction. In fact, the Ni-N- active sites anchored to the carbon structures have been proposed as excellent solution for the conversion CO2-to-CO, exceeding selectivity and partial current density values of the commercial electrocatalyst. Herein, the in-situ creation of Ni-N-active sites using Nickel Carbide nanoparticles-wrapped in a graphene shell (Ni3C@graphene NPs) and Emeraldine as precursors in combination with the thermal treatments is evaluated. As a result, the Ni-N- active sites in combination with Ni3C@graphene NPs provide a new paradigm, where the formate production is dominated leading a complete deactivation of CO route. Surprisingly, the unprecedent key performance indicators of the CO2 reduction showed a Faradaic Efficiency up to 90 % at 0.55V vs. RHE at 25ºC. Additionally, the CO2-to-formate conversion showed a temperature sensitive- dependence, increasing the selectivity (up to 96 %) in the voltage range tested (0.45 to 0.7V vs. RHE), when the electrolysis was performed at 40ºC. The apparent Energy Activation values СКАЧАТЬ