Atomic Layer Deposition in Energy Conversion Applications

Julien Bachmann is Professor of Inorganic Chemistry at the Friedrich-Alexander University of Erlangen-Nürnberg in Erlangen, Germany. He obtained his chemistry diploma from the University of Lausanne, Switzerland, and a PhD in inorganic chemistry from the Massachusetts Institute of Technology in Boston, USA. After an Alexander von Humboldt postdoctoral fellowship at the Max Planck Institute of Microstructure Physics in Halle, Germany, he was hired as a Junior Professor of Applied Physics at the University of Hamburg, Germany, before joining the faculty in Erlangen.

• Preface xiJulien BachmannThe Past of Energy Conversion xiThe Future of Energy Conversion xiTechnical Ingredients Needed xiiiScope of This Book xivPhotovoltaics: Strategies, Length Scales, and ALD xvElectrochemical Energy Storage: Principles, Chemistries, and ALD xviiOther Energy Conversion Strategies Based on Interfaces xixReferences xxList of Contributors xxiiiPart I Introduction to Atomic Layer Deposition 11 Basics of Atomic Layer Deposition: Growth Characteristics and Conformality 3Jolien Dendooven and Christophe Detavernier1.1 Atomic Layer Deposition 31.1.1 Principle of ALD 31.1.2 ALD Growth Characteristics – Linearity, Saturation, and ALD Window 51.1.3 Plasma-Enhanced ALD 81.2 In Situ Characterization for Studying ALD Processes 111.2.1 Quartz Crystal Microbalance 121.2.2 Quadrupole Mass Spectrometry (QMS) 131.2.3 Spectroscopic Ellipsometry 141.2.4 Fourier Transform Infrared Spectroscopy 151.2.5 Optical Emission Spectroscopy 151.2.6 Other In Situ Techniques 161.3 Conformality of ALD Processes 161.3.1 Quantifying the Conformality of ALD Processes 171.3.2 Modeling the Conformality of ALD 211.3.3 The Conformality of Plasma-Enhanced ALD 241.3.4 Conformal Coating of Nanoporous Materials 29References 34Part II Atomic Layer Deposition in Photovoltaic Devices 412 Atomic Layer Deposition for High-Efficiency Crystalline Silicon Solar Cells 43Bart Macco, Bas W. H. van de Loo, and Wilhelmus M. M. Kessels2.1 Introduction to High-Efficiency Crystalline Silicon Solar Cells 432.1.1 ALD for Si Homojunction Solar Cells 442.1.2 ALD for Si Heterojunction Solar Cells 462.1.3 Novel Passivating Contacts and ALD 472.1.4 Outline of this Chapter 472.2 Nanolayers for Surface Passivation of Si Homojunction Solar Cells 482.2.1 Basics of Surface Passivation 482.2.2 Surface Passivation by ALD Al2O3 542.2.3 ALD in Solar Cell Manufacturing 592.2.4 New Developments for ALD Passivation Schemes 632.3 Transparent Conductive Oxides for Si Heterojunction Solar Cells 682.3.1 Basics of TCOs in SHJ Solar Cells 692.3.2 ALD of Transparent Conductive Oxides 742.3.3 High-Volume Manufacturing of ALD TCOs 792.4 Prospects for ALD in Passivating Contacts 802.4.1 Basics of Passivating Contacts 802.4.2 ALD for Passivating Contacts 862.5 Conclusions and Outlook 89References 903 ALD for Light Absorption 101Alex Martinson3.1 Introduction to Solar Light Absorption 1013.2 Why ALD for Solar Light Absorbers? 1043.2.1 Uniformity and Precision of Large-Area Coatings 1043.2.2 Orthogonalizing Light Harvesting and Charge Extraction 1053.2.3 Pinhole-Free Ultrathin Films, ETA Cells 1073.2.4 Chemical Control of Stoichiometry and Doping 1073.2.5 Low-Temperature Epitaxy 1093.3 ALD Processes for Visible and NIR Light Absorbers 1093.3.1 ALD Metal Oxides for Light Absorption 1113.3.2 ALD Metal Chalcogenides for Light Absorption 1113.3.3 Other ALD Materials for Light Absorption 1153.4 Prospects and Future Challenges 115References 1154 Atomic Layer Deposition for Surface and Interface Engineering in Nanostructured Photovoltaic Devices 119Carlos Guerra-Nuñez, Hyung Gyu Park, and Ivo Utke4.1 Introduction 1194.2 ALD for Improved Nanostructured Solar Cells 1204.2.1 Compact Layer: The TCO/Metal Oxide Interface 1214.2.2 Blocking Layer: The Metal Oxide/Absorber Interface 1264.2.3 Surface Passivation and Absorber Stabilization: The Absorber/HTM Interface 1304.2.4 Atomic Layer Deposition on Quantum Dots 1324.2.5 ALD on Large-Surface-Area Current Collectors: Compact Blocking Layers 1344.3 ALD for Photoelectrochemical Devices for Water Splitting 1384.4 Prospects and Conclusions 142References 143Part III ALD toward Electrochemical Energy Storage 1495 Atomic Layer Deposition of Electrocatalysts for Use in Fuel Cells and Electrolyzers 151Lifeng Liu5.1 Introduction 1515.2 ALD of Pt-Group Metal and Alloy Electrocatalysts 1535.2.1 ALD of Pt Electrocatalysts 1545.2.2 ALD of Pd Electrocatalysts 1685.2.3 ALD of Pt-Based Alloy and Core/Shell Nanoparticle Electrocatalysts 1695.3 ALD of Transition Metal Oxide Electrocatalysts 1745.4 Summary and Outlook 175Acknowledgment 178References 1786 Atomic Layer Deposition for Thin-Film Lithium-Ion Batteries 183Ola Nilsen, Knut B. Gandrud, Amund Ruud, and Helmer Fjellvåg6.1 Introduction 1836.2 Coated Powder Battery Materials by ALD 1846.3 Li Chemistry for ALD 1866.4 Thin-Film Batteries 1876.5 ALD for Solid-State Electrolytes 1896.5.1 Li2CO3 1896.5.2 Li–La–O 1896.5.3 LLT 1896.5.4 Li–Al–O (LiAlO2) 1906.5.5 LixSiyOz 1916.5.6 Li–Al–Si–O 1916.5.7 LiNbO3 1926.5.8 LiTaO3 1926.5.9 Li3PO4 1926.5.10 Li3N 1926.5.11 LiPON 1936.5.12 LiF 1946.6 ALD for Cathode Materials 1946.6.1 V2O5 1946.6.2 LiCoO2 1956.6.3 MnOx/Li2Mn2O4/LiMn2O4 1966.6.4 Subsequent Lithiation 1966.6.5 LiFePO4 1976.6.6 Sulfides 1986.7 ALD for Anode Materials 1986.8 Outlook 199Acknowledgments 204References 2047 ALD-Processed Oxides for High-Temperature Fuel Cells 209Michel Cassir, Arturo Meléndez-Ceballos, Marie-Hélène Chavanne, Dorra Dallel, and Armelle Ringuedé7.1 Brief Description of High-Temperature Fuel Cells 2097.1.1 Solid Oxide Fuel Cells 2097.1.2 Molten Carbonate Fuel Cells 2107.2 Thin Layers in SOFC and MCFC Devices 2107.2.1 General Features 2107.2.2 Interest of ALD 2127.3 ALD for SOFC Materials 2137.3.1 Electrolytes and Interfaces 2137.3.2 Electrodes and Current Collectors 2157.4 Coatings for MCFC Cathodes and Bipolar Plates 2167.5 Conclusion and Emerging Topics 218References 218Part IV ALD in Photoelectrochemical and Thermoelectric Energy Conversion 2238 ALD for Photoelectrochemical Water Splitting 225Lionel Santinacci8.1 Introduction 2258.2 Photoelectrochemical Cell: Principle, Materials, and Improvements 2278.2.1 Principle of the PEC 2278.2.2 Photoelectrode Materials 2288.2.3 Geometry of the Photoelectrodes: Micro- and Nanostructuring 2308.2.4 Coating and Functionalization of the Photoelectrodes 2338.3 Interest of ALD for PEC 2338.3.1 Synthesis of Electrode Materials 2348.3.2 Nanostructured Photoelectrodes 2358.3.3 Catalyst Deposition 2398.3.4 Passivation and Modification of the Junction 2408.3.5 Photocorrosion Protection 2448.4 Conclusion and Outlook 247References 2479 Atomic Layer Deposition of Thermoelectric Materials 259Maarit Karppinen and Antti J. Karttunen9.1 Introduction 2599.1.1 Thermoelectric Energy Conversion and Cooling 2599.1.2 Designing and Optimizing Thermoelectric Materials 2609.1.3 Thin-Film Thermoelectric Devices 2629.2 ALD Processes for Thermoelectrics 2639.2.1 Thermoelectric Oxide Thin Films 2639.2.2 Thermoelectric Selenide and Telluride Thin Films 2669.3 Superlattices for Enhanced Thermoelectric Performance 2669.4 Prospects and Future Challenges 271References 272Index 275