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Fabrication of High Quality Periodic Structures Through Convective Assembly Procedures Midhun Joy Lehigh University

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Lehigh University Lehigh Preserve Theses and Dissertations 2016 Fabrication of high quality periodic structures through convective assembly procedures Midhun Joy Lehigh University Follow this and additional works at: http://preserve.lehigh.edu/etd Part of the Chemical Engineering Commons Recommended Citation Joy, Midhun, "Fabrication of high quality periodic structures through convective assembly procedures" (2016). Theses and Dissertations. 2651. http://preserve.lehigh.edu/etd/2651 This Dissertation is brought to you for free and open access by Lehigh Preserve. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of Lehigh Preserve. For more information, please contact [email protected]. Fabrication of high quality periodic structures through convective assembly procedures by Midhun Joy Presented to the Graduate and Research Committee of Lehigh University in Candidacy for the Degree of Doctor of Philosophy in Chemical Engineering Lehigh University September 2016 Copyright by Midhun Joy 2016 ii Certificate of Approval Approved and recommended for acceptance as a dissertation in partial fulfillment of the requirements of the degree of Doctor of philosophy. ________________ Date _________________________ _________________________ James F. Gilchrist, Ph.D. Mark A. Snyder, Ph.D. Dissertation advisor Dissertation advisor ________________ Accepted date Committee Members: ___________________________ James F. Gilchrist, Ph.D. Committee chair ____________________________ Mark A. Snyder, Ph.D. Committee member ____________________________ Martin P. Harmer, Ph.D. Committee member ____________________________ Hugo S. Caram, Ph.D. Committee member iii Acknowledgements Today, when I finish five years of my PhD life, I am really thankful to some great people I have come across in my life for their inspiration, guidance, support and help without which this dissertation would not have been possible. No words of acknowledgment would be sufficient to express my gratitude towards my advisors, colleagues, friends and family for devoting their time and energy, inspiring me to be successful as a researcher. I am immensely grateful to my advisors Prof. James F. Gilchrist and Prof. Mark A. Snyder for mentoring me throughout the past five years as a doctoral student- both as research advisors who would always guide me in my research and also as friends with whom I could confide my personal struggles. I am deeply indebted to my advisors for taking me as a group member in spite of the lack of any experimental background and constantly motivating me when I encountered several obstacles during my research years. The bulk of my dissertation would not have been possible, if not for my advisors who inspired me to explore uncharted territories and perform detailed studies when I came across certain unexpected observations during the course of my experiments. Thank you Professors for your patience with me, for your guiding and supporting hands, for inspiring me to take up challenges, teaching me to be systematic as a researcher and persuading me to have belief and confidence in my capabilities. I would like to express my sincere gratitude to the members of my dissertation committee- Prof. Hugo S. Caram and Prof. Martin A. Harmer for their valuable suggestions and insights regarding the research work. Also, the discussions on crystallography and crystal defects which I had with Prof. Chris Kiely deserves special acknowledgement, iv without which I would not have been able to gain a mechanistic understanding of the periodic patterns reported in the dissertation – the discussions enabled a theoretical analysis as well as model building tasks which replicated the observed patterns. Also, I would like to express my gratitude to the faculty at the department of chemical engineering at Lehigh University who taught me various courses during the span of my PhD research. Moreover, my PhD research at Lehigh University would not have been possible, but for the funding I received from various sources during the course of my studies. I would like to acknowledge the research funding received from Lehigh University (Gotshall Research Fellowship) as well as the funding from NSF, Power Optics LLC, Pennsylvania Nanomaterials Commercialization Center and CBET: Energy for Sustainability. I am equally indebted to my lab mates in both Prof. Gilchrist’s lab as well as Prof. Snyder’s lab who made me feel at ease when I joined the lab and have been an unrelenting source of guidance and help since then. I am greatly thankful for the guidance I received from Pisist Kumnorkaew (Pao) who patiently taught me even the basics of doing experiments, never losing his temper in spite of several chemical spills and innumerable experiments which went awry, teaching me to perform experiments in an efficient, focused and systematic manner. I would also like to thank my other lab mates, namely, Dr. Daniels for his suggestions regarding particles and for allowing me to use the chemicals and instruments of EPI lab, Alex, Zheng, Bonny & Cooper for their training on various lab instruments and particle synthesis, Erg for training me to use SEM and his valuable help and suggestions regarding the vibration-assisted convective deposition project and Tharanga who trained me on using the confocal microscope. Also valuable is the research v guidance and help I have received from Dan, Minseok, Kedar, Naval and Megha, who were always willing to spare their time to help me out in my projects. Also, thanks to John Caffrey who developed the designs for various experimental set-ups and fabricated them, William Mushock (Bill) who was always happy to help with whatever issues I had with SEM. I would also like to thank the professors and students who allowed me to use their instruments and trained me on them- Prof. Manoj Choudhary, Partho and Aditi for their help with contact angle measurements and high speed imaging, Prof. Anand Jagota and Dadhichi Paretkar for profilometer and spin coating instruments, Prof. Xuanhong Chengand Krissada (Chai) for plasma-based surface treatment, Prof. Nelson Tansu and Wei Sun for the use of farfield measurement setups and RamaraoVemula for resolving instrumentation issues with various setups. Thanks are also due to my classmates and staff in the department, especially Barbara, Tracey and Janine who were always willing to help me out whenever I was in need. My life as a graduate student at Lehigh would not have been the same if not for my friends who gave me several memories of fun and excitement outside my research life – Rinosh, Ashwin, Abhinay, Antony, Rahul, Vivek, Anoop, Avinash, Prasad, Hari..just to mention a few in the long list of my friends who took turns to teach me driving and to take me for shopping and other outdoor activities. My friends outside Lehigh University also deserve a special mention for devoting their time and resources for me. I am not sure if I could ever thank properly Sr. Clare and Sr. Clarice for all that they have done for me, giving me a home away from home in the U.S and being ever ready to help me out in my life- the innumerable dinners prepared for me as well as for the several dozens of gifts on all occasions of my life. Also deserving special mention is Mr. Linson and family as well vi as Prisca Vidanage for the several rides, whenever in need. On this occasion, I would also like to thank Prof. Niket Kaisare, who being my advisor during Masters program motivated me to do PhD and was instrumental in my applying for and gaining admission at Lehigh University. Thank you all. It also gives me immense pleasure to thank my family for all that they have done for me. My parents, who always loved me and strived to provide the best for me as well as my brothers Jithin and Nidhin who have given me uncountable childhood memories. I would also like to mention my wife, Grace who entered into my life as a partner-for-life during the last semester of my PhD program and has been a great source of love, inspiration and support since then. Equally loving and caring have been my in-laws, especially my close friend and brother-in-law Roger. Above all, I would like to acknowledge the bountiful blessings I have received from Almighty God, who has made His presence, love and power felt throughout my life through several instances which I had often passed over to just being lucky or a mere coincidence. To my advisors, colleagues, friends and my family – I thank you all from the bottom of my heart. Midhun Joy vii Table of Contents List of Tables ................................................................................................................... xii List of Figures ................................................................................................................. xiii Abstract ...............................................................................................................................1 1. Introduction ................................................................................................................... 5 1.1 Self-assembly procedures for advanced functional materials .............................. 6 1.2 Colloidal crystal structures through self-assembly procedures ............................ 8 1.3 Convective self-assembly of particles into colloidal crystals ............................ 14 1.3.1 Background of conventional convective self-assembly processes ............. 14 1.3.2 Morphology of particle assemblies in convective deposition ..................... 18 1.3.3
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