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Advanced Electrodes and Electrolytes for Long-Lived and High- Performance Lithium-Sulfur Batteries

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Advanced Electrodes and Electrolytes for Long-Lived and High- Performance Lithium-Sulfur Batteries Wayne State University Wayne State University Dissertations January 2020 Advanced Electrodes And Electrolytes For Long-Lived And High- Performance Lithium-Sulfur Batteries Deepesh Gopalakrishnan Wayne State University Follow this and additional works at: https://digitalcommons.wayne.edu/oa_dissertations Part of the Chemical Engineering Commons, Materials Science and Engineering Commons, and the Nanoscience and Nanotechnology Commons Recommended Citation Gopalakrishnan, Deepesh, "Advanced Electrodes And Electrolytes For Long-Lived And High-Performance Lithium-Sulfur Batteries" (2020). Wayne State University Dissertations. 2448. https://digitalcommons.wayne.edu/oa_dissertations/2448 This Open Access Dissertation is brought to you for free and open access by DigitalCommons@WayneState. It has been accepted for inclusion in Wayne State University Dissertations by an authorized administrator of DigitalCommons@WayneState. ADVANCED ELECTRODES AND ELECTROLYTES FOR LONG-LIVED AND HIGH-PERFORMANCE LITHIUM-SULFUR BATTERIES by DEEPESH GOPALAKRISHNAN DISSERTATION Submitted to the Graduate School of Wayne State University, Detroit, Michigan in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY 2020 MAJOR: MECHANICAL ENGINEERING Approved By: Advisor Date DEDICATION Dedicated to my parents Mr. Gopalakrishnan and Mrs. Pushpalatha, my sister Divya, my wife Aparna Unni, my nephews Aadhi and Adhiseshan, my brother in law Udayasankaran, and my best friend Sandeep Nair, who have always supported me through unconditional love. ii ACKNOWLEDGMENTS Firstly, I would like to thank my advisor Dr. Leela Mohana Reddy Arava for giving me the wonderful opportunity to complete my Ph.D. thesis under his supervision, it is truly an honor. Thank you for all the advices, ideas, moral support, and patience in guiding me throughout this project. I appreciate all your contributions of time and funding to make my Ph.D. experience productive and stimulating. Your wealth of knowledge in the field of Material Science & Batteries is always inspiring. Thank you for giving me the opportunity to grow in this field of battery research. Also, I would like to acknowledge National Science Foundation (grant nos. 1751472, 1748363), ACS Petroleum Research Fund (ACSPRF: 57647-DNI10) and Hartley Family Foundation through Rice University (Contract R07721) for the funding support of my research. I would like to thank Dr. Xin Wu, Dr. Guru Dinda, Dr. Ratna naik and Dr. Mahbub Islam for being on my doctoral committee and providing with useful critiques for my work. I thank my department chair Dr. Nabil Chalhoub and Secretary Lisa Rapicano for their help and support in getting approvals done quickly. I thank Dr.Verani and Dr. Rabuffetti from Department of Chemistry, Wayne state university for giving me access to their labs for the synthesis and characterization of different materials used for my Ph.D research works. Also, I would like to thank Dr. Zhi Mei, Department of Chemistry, Wayne State University for helping me with SEM and TEM samples. I am deeply grateful to my former advisors Dr. Pradeep Thalappil (IIT Madras, India), Dr. M.M. Shaijumon (IISER TVM, India) and Dr. Seeram Ramakrishna (NUS, Singapore) for introducing me to the filed of research on material sciences and for keeping me always motivated. I extend my sincere gratitude for Dr. Sreejith Sivaramapanicker, Dr. Sreeprasad Sreenivasan, Dr. Girilal, Dr. Adarsh P, Dr. Molamma Prabhakaran, Dr. S. Balakumar, Dr. Prasanth krishnan and Dr. Dijo Damien for their support, guidance and valuable suggestions throughout my research iii career. I sincerely thank Dr. Renjith Sasi, Dr. Ayana Baskaran and Dr. Binitha G for their personal and scholarly interactions, suggestions at various points of my research programme. I am thankful to my colleagues at the Functional Nanomaterials and energy devices laboratory for providing their support in my research work: Dr. Hesham Al Salem, Dr. Bhuvaneshwari Dharmarajan, Dr. Khalid Ababtain, Dr. Nirul Masurkar, Abdualrazzag Sawas, Uday Praveen, Kiran Mahankali, Sathish Rajendran, Sudhan Nagarajan and Sanjeev Porchelvan. I am grateful to work with Dr. Babu Ganguli and Dr. Naresh Thangavel who helped me a lot and cleared my scientific doubts throughout my Ph.D. journey. A special thanks for Dr. Munaiah Yeddala for helping me in correcting and modifying the thesis. I had immense pleasure in guiding and nurturing research study of undergraduate and graduate students Neha Bhagirath, Ann Amarachi Mark, Andrew Lee, Samia Alkatie, Deviprasad, Victoria Lebryk, Rijo John and Raghavendra. I would like to thank my parents Mr. Gopalakrishnan and Mrs. Pushpalatha, my sister Divya, my nephews Aadhi and Adhiseshan, my brother in law Udayasankaran for their endless encouragement in all my pursuits and inspiring me to follow my dreams. I am especially grateful to my parents and my sister, who supported me emotionally and believed in me and wanted the best for me. And most of all for my loving, supportive, and encouraging wife Aparna whose faithful support during the final stages of this Ph.D. is also greatly appreciated. Special thanks to my in-laws Mr. Unnikrishnan, Mrs. Suja and Harikrishnan for their love, care, and support. Thank you, my best friend and brother Sandeep Nair, for your love and support, sense of humor, and advice, was more valuable than you could ever imagine. And special thanks to Dr. Sreeja Sekhar and Dr. Arun Sankar for listening, offering me advice, and supporting me through this entire process. Also, Thank you my “Poker Buddies” for all your love, care, wishes, prayers, and constant support. iv TABLE OF CONTENTS Dedication ……………………………………………………………………………………….ii Acknowledgments……………………………………………………………………………….iii List of Tables…………...………………………………………………………………………..ix List of Figures ..…………………………………………………………………………….........x Chapter 1 Introduction…………………………………………………………………………..1 1.1 Lithium Ion Batteries…………………………………………………………………..1 1.2 Working principle of a lithium-ion battery…………………………………………….3 1.3 Challenges of Lithium Ion Batteries…………………………………………………...5 1.4 Li -O2 and Li-S chemistry……………………………………………………………...7 1.5 Li-S batteries…………………………………………………………………………..8 1.6 Problems and challenges……………………………………………………………..11 1.7 Proposed strategies towards suppressing polysulfides and Li dendrites……………...17 1.7.1 Strategies to prevent polysulfide shuttling process in Li-S batteries……………….17 1.7.2 strategies towards Li dendrite suppression…………………………………………19 1.8 Scope of the study…………………………………………………………………….24 Chapter 2 Experimental methods………… ……………………………………………….….26 2.1 Material Characterization Techniques for Electrocatalysts………………………….26 2.1.1 X-ray diffraction spectrometer……………………………………………..26 v 2.1.2 Scanning Electron Microscopy……………………………………………..27 2.1.3 Transmission Electron Microscopy .………………………………………. 28 2.1.4 Optical Absorption Spectroscopy…………………………………………..28 2.1.5 X-ray Photoemission Spectroscopy……………………………………….. 28 2.1.6 Thermal studies……………………………………………………………. 29 2.1.7 Raman spectroscopy………………………………………………………..30 2.2 Characterization of Ionic Liquid Crystal electrolytes………………………………..30 2.2.1 Nuclear Magnetic Resonance spectroscopy.……………………………….31 2.2.2 Fourier transform infrared spectrometer…………………………………..31 2.2.3 Differential Scanning Calorimetry………………………………………....31 2.2.4 Polarized light microscopy…………………………………………………32 2.2.5 Wide-angle X-ray diffraction and Small Angle X-ray Scattering…………..32 2.2.6 Anisotropy conductivity measurements……………………………………. 33 2.3 Electrochemical Testing……………………………………………………………...34 2.3.1 Cyclic voltammetry ………………………………………………………...34 2.3.2 Electrochemical impedance spectroscopy…………………………………34 2.3.3 Chronoamperometry……………………………………………………….35 2.3.4 Tafel plot……………………………………………………………………35 vi Chapter 3 Understanding heterogeneous electrocatalysis of lithium polysulfide redox on Pt and WS2 surfaces………………………………………………………………….. 37 3.1 Background and Motivation…………………………………………………………………37 3.2 Experimental Methods………………………………………………………………………. 39 3.2.1 Preparation of lithium polysulfides …………………………………………..39 3.2.2 Adsorption studies……………………………………………………………….39 3.2.3 Electrochemical studies ………………………………………………………..39 3.2.4 Chronocoulometric method…………………………………………………….40 3.2.5 Li2S Nucleation studies…………………………………………………………40 3.2.6 Electrochemical Impedance……………………………………………………40 3.2.7 Coin Cell fabrication and electrochemical measurements…………………41 3.3 Results and discussion………………………………………………………………………..41 3.3.1 Electrocatalysis in LiPS reduction…………………………………………….41 3.3.2 Electrocatalysis in LiPS oxidation…………………………………………….48 3.3.3 Adsorption of polysulfide on catalytic interface……………………………...51 3.3.4 Li2S2/ Li2S growth on the catalytic interface …………………………….53 3.4 Conclusion…………………………………………………………………………………… .59 Chapter 4 Facile synthesis of electrocatalytically active NbS2 nanoflakes for energy-related electrocatalysis………………………………………………………………………......60 4.1 Background and Motivation………………………………………………………… 60 4.2 Experimental methods………………………………………………………………..63 4.3 Results and Discussion……………………………………………………………… 64 4.3.1 HER studies of NbS2 nanoflakes and NbS2/rGO……………………………70 vii 4.3.2 Lithium Sulfur Battery studies of NbS2 nanoflakes and NbS2/CC………….74 4.4 Conclusion……………………………………………………………………………79 Chapter 5 Ionic liquid crystalline electrolyte to suppress dendrite growth in Li metal batteries: an effect of anisotropic mass transport…………………………………….81 5.1 Background and Motivation………………………………………………………….81 5.1.1 Liquid Crystals and Ionic Liquid Crystals………………………………….82
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