Computational Approaches to Energy Materials

Professor Richard Catlow is the Dean of the Faculty of Mathematical and Physical Sciences at University College London and a Fellow of the Royal Society. He has worked in the field of computational and experimental studies of complex inorganic materials for over 30 years, pioneering a wide range of applications of computational techniques.  His current research involves exploring the structures, properties and reactivities of complex materials including micro and mesoporous catalysts, electronic ceramics, minerals, fast ion conductors and molecular materials. Professor Catlow has published over 800 papers and authored or co-authored 12 books, including the widely used Computer Simulation of Solids and the influential Computer Modeling of Microporous Materials.Dr Alexey Sokol is a Senior Research Associate at University College London, where he has worked on the development and applications of computational methods for solid-state physics, chemistry and materials science for over 20 years. He has recently been involved with the development of multi-scale computational approaches to facilitate the accurate modelling of catalytic and defect processes in oxide and semiconducting materials.Dr Aron Walsh is a Marie Curie Fellow at University College London with a long standing interest in energy materials following postdoctoral work at the National Renewable Energy Laboratory (USA) where he still maintains close links. He has applied electronic structure techniques to the design of novel solar cell and solid-state lighting materials, and has pioneered a new field of theoretical research into semiconducting metal organic frameworks.

• About the Editors xi List of Contributors xiiiPreface xvAcknowledgments xvii1 Computational Techniques 1C. Richard A. Catlow, Alexey A. Sokol, and Aron Walsh1.1 Introduction 11.2 Atomistic Simulations 11.2.1 Basic Concepts 11.2.2 Parameterization 31.2.3 Parameter Sets 31.2.4 Implementation 41.3 Electronic Structure Techniques 61.3.1 Wavefunction Methods 81.3.1.1 Hartree–Fock Theory 91.3.1.2 Post-Hartree–Fock Approaches 101.3.1.3 Semi-empirical Wavefunction Methods 111.3.2 Density Functional Theory 121.3.2.1 Exchange–Correlation Functionals 121.3.2.2 Semi-empirical Density Functional Approaches 141.3.3 Excited States 151.4 Multiscale Approaches 151.4.1 Hybrid QM/MM Embedding Techniques 161.4.2 Beyond Atomistic Models 171.5 Boundary Conditions 191.6 Point-Defect Simulations 211.6.1 Mott–Littleton Approach 211.6.2 Periodic Supercell Approach 241.7 Summary 25References 252 Energy Generation: Solar Energy 29Silvana Botti and Julien Vidal2.1 Thin-Film Photovoltaics 292.2 First-Principles Methods for Electronic Excitations 322.2.1 Hedin’s Equations and the GW Approximation 342.2.2 Hybrid Functionals 382.2.3 Bethe–Salpeter Equation 402.2.4 Model Kernels for TDDFT 412.3 Examples of Applications 422.3.1 Cu-Based Thin-Film Absorbers 432.3.2 Delafossite Transparent Conductive Oxides 542.4 Conclusions 60References 613 Energy Generation: Nuclear Energy 71Dorothy Duffy3.1 Introduction 713.2 Radiation Effects in Nuclear Materials 723.2.1 Fission 723.2.1.1 Structural Materials 733.2.1.2 Fuel 763.2.1.3 Cladding 793.2.2 Fusion 803.2.2.1 Structural Materials 813.2.2.2 Plasma-Facing Materials 823.2.3 Waste Disposal 833.3 Modeling Radiation Effects 853.3.1 BCA Modeling 863.3.2 Molecular Dynamics 873.3.2.1 Cascade Simulations 873.3.2.2 Sputtering Simulations 933.3.3 Monte Carlo Simulations 943.3.3.1 Kinetic Monte Carlo 953.3.3.2 Object Kinetic Monte Carlo 963.3.3.3 Transition Rates 973.3.3.4 Examples 983.3.4 Cluster Dynamics 993.3.4.1 Examples 993.3.4.2 Comparison with OKMC 1003.3.5 Density Functional Theory 1013.3.5.1 Interatomic Potentials 1013.3.5.2 Transition Rates 1023.4 Summary and Outlook 102References 1044 Energy Storage: Rechargeable Lithium Batteries 109M. Saiful Islam and Craig A.J. Fisher4.1 Introduction 1094.2 Overview of Computational Approaches 1104.3 Li–Ion Batteries 1124.4 Cell Voltages and Structural Phase Stability 1134.5 Li–Ion Diffusion and Defect Properties 1164.6 Surfaces and Morphology 1214.7 Current Trends and Future Directions 1244.8 Concluding Remarks 125References 1255 Energy Storage: Hydrogen 131Viet-Duc Le and Yong-Hyun Kim5.1 Introduction 1315.2 Computational Approach in Hydrogen Storage Research 1335.3 Chemisorption Approach 1335.4 Physisorption Approach 1365.5 Spillover Approach 1385.6 Kubas-Type Approach 1385.7 Conclusion 145References 1466 Energy Conversion: Solid Oxide Fuel Cells 149E.A. Kotomin, R. Merkle, Y.A. Mastrikov, M.M. Kuklja, and J. Maier6.1 Introduction 1496.2 Computational Details 1526.3 Cathode Materials and Reactions 1556.3.1 Surfaces: LaMnO3 and (La,Sr)MnO3 Perovskites 1556.3.1.1 Surface Termination, Surface Point Defects 1556.3.1.2 Oxygen Adsorption and Diffusion 1586.3.1.3 Rate-Determining Step of the Surface Reaction 1606.3.2 Bulk Properties of Multicomponent Perovskites 1646.3.2.1 Oxygen Vacancy Formation in (Ba,Sr)(Co,Fe)O3−δ 1646.3.2.2 Oxygen Vacancy Migration in (Ba,Sr)(Co,Fe)O3−δ 1676.3.2.3 Disorder and Cation Rearrangement in (Ba,Sr)(Co,Fe)O3−δ 1706.3.3 Defects in (La,Sr)(Co,Fe)O3−δ 1736.4 Ion Transport in Electrolytes: Recent Studies 1756.5 Reactions at SOFC Anodes 1766.6 Conclusions 177Acknowledgments 178References 1787 Energy Conversion: Heterogeneous Catalysis 187Rutger A. van Santen, Evgeny A. Pidko, and Emiel J.M. Hensen7.1 Introduction 1877.1.1 Particle Size Dependence of Catalytic Reactivity 1917.1.2 Activity and Selectivity as a Function of the Metal Type 1927.1.3 Reactivity as a Function of State of the Surface 1937.1.4 Mechanism of Acid Catalysis: Single Site versus Dual Site 1937.2 Basic Concepts of Heterogeneous Catalysis 1957.3 Surface Sensitivity in CH Activation 1987.3.1 Homolytic Activation of CH Bonds 1987.3.2 Heterolytic Activation of CH Bonds 2037.3.2.1 Brønsted Acid Catalysis 2047.3.2.2 Lewis Acid Catalysis 2067.4 Surface Sensitivity for the C−C Bond Formation 2097.4.1 Transition Metal Catalyzed FT Reaction 2097.4.2 C−C Bond Formation Catalyzed by Zeolitic Brønsted Acids 2137.5 Structure and Surface Composition Sensitivity: Oxygen Insertion versus CH Bond Cleavage 2177.5.1 Silver-Catalyzed Ethylene Epoxidation 2177.5.2 Benzene Oxidation by Iron-Modified Zeolite 2217.6 Conclusion 223References 2248 Energy Conversion: Solid-State Lighting 231E. Kioupakis, P. Rinke, A. Janotti, Q. Yan, and C.G. Van de Walle8.1 Introduction to Solid-State Lighting 2318.2 Structure and Electronic Properties of Nitride Materials 2348.2.1 Density Functional Theory and Ground-State Properties 2348.2.2 Electronic Excitations: GW and Exact Exchange 2368.2.3 Electronic Excitations: Hybrid Functionals 2408.2.4 Band-gap Bowing and Band Alignments 2408.2.5 Strain and Deformation Potentials 2418.3 Defects in Nitride Materials 2438.3.1 Methodology 2448.3.2 Example: C in GaN 2468.4 Auger Recombination and Efficiency Droop Problem of Nitride LEDs 2488.4.1 Efficiency Droop 2488.4.2 Auger Recombination 2498.4.3 Computational Methodology 2518.4.4 Results 2528.5 Summary 254Acknowledgments 255References 2559 Toward the Nanoscale 261Phuti E. Ngoepe, Rapela R. Maphanga, and Dean C. Sayle9.1 Introduction 2619.2 Review of Simulation Methods 2639.2.1 Established Computational Methods 2639.2.2 Evolutionary Methods 2639.2.2.1 GM Methods 2639.2.2.2 Amorphization and Recrystallization 2649.3 Applications 2669.3.1 Nanoclusters 2669.3.1.1 ZnO 2669.3.1.2 ZnS 2689.3.1.3 MnO2 2699.3.1.4 TiO2 2719.3.2 Nanoarchitectures 2729.3.2.1 MnO2 Nanoparticle (Nucleation and Crystallization) 2729.3.2.2 MnO2 Bulk 2759.3.2.3 MnO2 Nanoporous 2789.3.2.4 TiO2 Nanoporous 2849.3.2.5 ZnS and ZnO Nanoporous 2869.4 Summary and Conclusion 289Acknowledgments 290References 290Further Reading 295Index 297