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Water Splitting by Heterogeneous Catalysis

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!"#$ #"%"" &' () * ( +# ,% - . ( (.( ( . %/ .0! 1 ( % 2 3 . 4 . 5 % . . % . . . . . . 3 % !# 3 ( 3 ( 3 ( 3 %/. . - % . (. 6 7 % ( 2!0! . (/ (3 . 7 % ( ( 3 % . 3 ( %/ . 8 9 3 8 % ( :;0 9 . <= 3 9 . % ( . ( 3 > % !"#$ ?@@ %% @ A B ?? ? ? #;C#C# ,8D$CD#$$D$":D! ,8D$CD#$$D$";"C ! " # $ (#" D# WATER SPLITTING BY HETEROGENEOUS CATALYSIS Henrik Svengren Water splitting by heterogeneous catalysis Henrik Svengren ©Henrik Svengren, Stockholm University 2017 ISBN print 978-91-7797-039-2 ISBN PDF 978-91-7797-040-8 Printed in Sweden by Universitetsservice US-AB, Stockholm 2017 Distributed by the Department of Materials and Environmental Chemistry To my beloved family Cover image + Heterogeneous catalysis of water oxidation according to 2H2O ĺ O2 + 4H on CoSbO4/CoSb2O6, investigated in Paper II. The figure is composed of SEM- and TEM images, structural drawings, reactant- and product molecules. i Examination Faculty opponent Docent Tomas Edvinsson Solid State Physics Department of Engineering Sciences Uppsala University, Uppsala, Sweden Evaluation committee Professor Ann Cornell Applied Electrochemistry School of Chemical Science and Engineering KTH Royal Institute of Technology, Stockholm, Sweden Professor Mats Jonsson Applied Physical Chemistry School of Chemical Science and Engineering KTH Royal Institute of Technology, Stockholm, Sweden Docent Fredrik Björefors Structural Chemistry Department of Chemistry, Ångström Laboratory Uppsala University, Uppsala, Sweden Substitute, evaluation committee Professor Aji Mathew Department of Materials and Environmental Chemistry Stockholm University, Stockholm, Sweden Chairman at the dissertation act Professor Dag Noréus Department of Materials and Environmental Chemistry Stockholm University, Stockholm, Sweden ii List of publications This thesis is based on the following publications referred to by the Roman numerals I-V in the text. The papers appear at the end of the thesis. Paper I Water splitting catalysis studied by real time Faradaic efficiency obtained by coupled electrolysis and mass spectrometry Henrik Svengren, Mylad Chamoun, Jekabs Grins, Mats Johnsson ChemElectroChem (2017) DOI: 10.1002/celc.201701086 Reproduced by permission of Wiley. My contribution: I conducted development of the method, construction of the analytical cell, electrode preparations, characterization by electrochemical and chemical water oxidation experiments, BET-analysis, mass spectrometry and the major part in writing; except synthesis and phase characterization of perovskite and RP-phases. Paper II Frontispiece: Direct Synthesis of Two Inorganic Catalysts on Carbon Fibres for the Electrocatalytic Oxidation of Water Henrik Svengren, Kjell Jansson, Jekabs Grins, Wei Wan, Natallia Torapava, Mats Johnsson Chemistry a European Journal 23 (2017) 568 – 575 Reproduced by permission of Wiley. My contribution: I conducted synthesis of materials, construction of the analytical cell, electrode preparations, characterization by electrochemical experiments and SEM-EDS and the major part in writing; except EXAFS interpretation, TEM/RED and ICP analysis. iii Paper III A transition metal oxofluoride offering advantages in electrocatalysis and potential use in applications Henrik Svengren, Natallia Torapava, Ioannis Athanassiadis, Sk Imran Ali, Mats Johnsson Faraday Discussions 188 (2016) 481-498 Reproduced by permission of Royal Society of Chemistry. My contribution: I conducted electrode preparations, construction of the analytical cell, characterization by electrochemical experiments, mass spectrometry and SEM-EDS and the major part in writing; except EXAFS/EXANES interpretation, ICP analysis and materials synthesis. Paper III Appendix Application of novel catalysts: general discussion Amy L. Miller, Michael Bowker, Andrés García-Trenco, Joseph Socci, Nia Richards, Graham Hutchings, Nicola Collis, James Earley, Simon Freakley, Robbie Burch, Mark Howard, Elad Gross, Andrzej Kotarba, Miron V. Landau, James Anderson, Bert Weckhuysen, Simon Kondrat, Evgeny Naranov, John Mark Douthwaite, Ram Tiruvalam, Sarwat Iqbal, Luke Parker, Parag Shah, Ewa Nowicka, Wataru Ueda, Alessandro Piovano, Philip Landon, Nico Fischer, Christian Reece, Bruce Gates, Michael Lamb, Eoin Jackman, Tomasz Jakubek, Avelino Corma, Michael Claeys, Henrik Svengren, Cynthia Friend, David Lennon, Joshua Makepeace, Hazel Hunter, Haresh Manyar Faraday Discussions 188 (2016) 399-426 Reproduced by permission of Royal Society of Chemistry. My contribution: I participated in the RSC Faraday Discussions by presenting the research conducted in Paper III followed by discussing the difficulties in characterization of the active surface layer, the time scale of its formation and the difficulty in comparing results with literature according to the transcript in Faraday Discussions 188 (2016) 410-412. iv Paper IV An Oxofluoride Catalyst Comprised of Transition Metals and a Metalloid for Application in Water Oxidation Henrik Svengren, Shichao Hu, Ioannis Athanassiadis, Tanja. M. Laine, Mats Johnsson Chemistry a European Journal 21 (2015) 12991 – 12995 Reproduced by permission of Wiley. My contribution: I conducted construction of the analytical reaction cell system, chemical 18 water oxidation, including H2 O, experiments, characterization by mass spectrometry, electrochemical experiments, SEM-EDS and Vicker’s hardness test; except ICP analysis and materials synthesis. Paper V Cobalt Selenium oxohalides: catalysts for water oxidation Faiz Rabbani, Henrik Svengren, Iwan Zimmermann, Shichao Hu, Tanja Laine, Wenming Hao, Björn Åkermark, Torbjörn Åkermark, Mats Johnsson Dalton Transactions 43 (2014) 3984-3989 Reproduced by permission of Royal Society of Chemistry. My contribution: I conducted chemical water oxidation experiments and characterization by mass spectrometry, SEM-EDS and BET analysis; except materials synthesis, structure 18 determination with X-ray diffraction and H2 O oxidation. v The following publications are not included in the thesis. Sediment accumulation rates determined by radiometry of 210Pb obtained from a sediment core co-analyzed for heavy metals in Lake Nakuru, Kenya Henrik Svengren, Per Roos, Daniel Koros, Gunnar Svensson Submitted for publication Relatedness and genetic variation in wild and captive populations of Mountain Bongo in Kenya obtained from genome-wide single-nucleotide polymorphism (SNP) data Henrik Svengren, Mike Prettejohn, Donald Bunge, Peter Fundi, Mats Björklund Global Ecology & Conservation 11 (2017) 196-206 National Large Scale Wetland Creation in Agricultural Areas –Potential versus Realized Effects on Nutrient Transports Stefan Weisner, Karin Johannesson, Geraldine Thiere, Henrik Svengren, Per Magnus Ehde, Karin Tonderski Water 8 (2016) 544 Hollow titania spheres loaded with noble metal nanoparticles for photocatalytic water oxidation Haoquan Zheng, Henrik Svengren, Zhehao Huang, Xiaodong Zou, Mats Johnsson Submitted for publication vi Well-Defined Palladium Nanoparticles Supported on Siliceous Mesocellular Foam as Heterogeneous Catalysts for the Oxidation of Water Oscar Verho, Torbjörn Åkermark, Eric Johnston, Karl Gustafson, Cheuk-Wai Tai, Henrik Svengren, Markus Kärkäs, Jan-Erling Bäckvall, Björn Åkermark Chemistry a European Journal 21 (2015) 5909–5915 Effect of grain size reduction of AA2124 aluminium alloy powder compacted by spark plasma sintering Ahmed Eldesouky, Mats Johnsson, Henrik Svengren, Moataz Attallah, Hanadi Salem Journal of Alloys Compounds 609 (2014) 215–221 vii Contents 1. Introduction 1.1 Hydrogen in an energy-sustainable society 1.2 Infrastructure of modern hydrogen production and utilization 1.3 The use of hydrogen 1.4 The history of electrochemical water splitting 1.5 Present research in perspective 1.6 Water splitting in Nature 1.7 Major electrolysis techniques 1.7.1 Alkaline electrolysis (AE) 1.7.2 Proton exchange membrane (PEM) electrolysis 1.7.3 Solid oxide electrolysis (SOE) 1.8 The media in which reactions takes place 1.8.1 Solution used in reactions with chemical electron acceptor 1.8.2 Electrolyte in water electrolysis 1.9 Thermodynamics, Ohmic resistance and catalysis 1.9.1 Thermodynamics 1.9.2 Activation energy 1.9.3 Ohmic resistance 1.9.4 Cell potential dependence of pH and cell overpotential 1.9.5 Mass transport diffusion and electrode morphology 1.9.6 Catalysis: homogeneous- or heterogeneous catalysis, or in between? 1.9.7 Catalysis in a reducing environment viii 1.9.8 Catalysis in an oxidizing environment 1.10 Compounds investigated for catalysis included in this thesis 1.11 The aim of this thesis 2. Experimental 2.1 Design and construction of reaction cells for analysis of catalysis 2.1.1 Electrolyzer cell for real time faradaic efficiency of AE or PEM electrolysis 2.1.2 Large size closed quartz glass cell for light reactions and electrocatalysis 2.1.3 Medium size cell for both chemical oxidation and electrocatalysis 2.1.4 Small volume reaction cells for chemical oxidation 2.1.5 Electrode holder and pump for flowing electrolyte 2.2 Characterization using microscopy
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