Electrons, Protons, and Solvents in Carbon Nanotubes by Gregory Arthur Pilgrim Submitted in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Supervised by Professor Todd D. Krauss Department of Chemistry Arts, Sciences and Engineering School of Arts and Sciences University of Rochester Rochester, NY 2015 ii This thesis is dedicated to the graduate students of the Laboratory for Electronic Ceramics at Alfred University. For the last twenty years I’ve wanted to be as cool as you. “…and he that will not apply new remedies must expect new evils; for time is the greatest innovator; and if time of course alter things to the worse, and wisdom and council shall not alter them to the better, what will be the end?” Sir Francis Bacon, 1625 iii Biographical Sketch The author was born in Columbia, Maryland on August 25th 1988. He attended Rochester Institute of Technology from 2006 to 2009 and Alfred University from 2009 to 2010. He graduated from RIT with a Bachelor of Science degree in Chemistry in 2010 after which he began graduate studies at the University of Rochester. He received his Masters degree in Chemistry in 2012. Throughout his graduate career he has been advised by Professor Todd Krauss. He was awarded a Weissberger Fellowship in 2014. While at the University of Rochester he has published one paper and submitted one patent. Publications Gregory A. Pilgrim, Joanne W. Leadbetter, Fen Qiu, Anni J. Siitonen, Steven M. Pilgrim, and Todd D. Krauss, “Electron Conductive and Proton Permeable Vertically Aligned Carbon Nanotube Membranes” Nano Lett., 2014, 14 (4), pp 1728–1733 Gregory A. Pilgrim, Amanda R. Amori, Zhentao Hou, Fen Qui, Todd D. Krauss, “Simultaneous Evaluation of Proton and Electron Crossing In Carbon Nanotube Membranes” In Preparation Gregory A. Pilgrim, Chae Un Kim, Surendra K. Gupta, Sol M. Gruner, Todd D. Krauss, “Observation of Tetragonal Ice Confined in Carbon Nanotubes” In Preparation iv Patent Pending Membranes With Vertically Correlated Carbon Nanotubes, And Methods Of Making And Using Same, Patent Application Number 61/945,439 v Acknowledgements First and foremost I would like to say a massive thank you to my groupmates. It’s you, individually and collectively, that I’ve spent the last five years with, and it’s you that have made those years so pleasant. It’s been our discussions that have formed my views of what a scientist ought to be, and do. To Michael Odoi in particular, a source of insight and wisdom where it was sorely needed, a special thanks is due. To Sanela Lampa-‐Pastrik, for her insightful and speedy contributions to the assembly of this work, a large thank you is due as well. Next, thank you to my advisor, Todd Krauss. Todd kept the bills paid for the past five years, no small accomplishment in the current funding climate, and one I’m very grateful for. Todd also gave me significant leeway to look into things that interested me. Sometimes those things bore fruit, other times not. In any case I’m grateful for the chance to have looked. To my collaborators, of which there are many, a thank you for your uniting features: a willingness to help, and a patience with me as I learned. I would particularly like to thank Brian McIntyre of URnano, for his patience, his good humor, and for his efforts on behalf of my endeavors. Similarly, the staffs of the Cornell Nanoscale Facility, the Institute for Electronics and Nanotechnology and the Cornell High Energy Synchrotron Source have all been exceedingly kind to me, and patient with my less-‐than-‐orthodox ideas for their equipment. Thank you all. To the staff of the Chemistry Department, who provided the underlying structure for all of this, a big thank you. vi To the extended swimming community, including but not limited to, the Rochester Monroe County Certified Swim Officials, the University of Rochester Masters Swim Team swimmers and staff, and my friends, coaches, and teammates from USA and NCAA Swimming, thank you for your camaraderie, enthusiasm, and particularly for the perspective that comes with knowing that maintaining mental focus is one thing but maintaining mental focus without breathing is quite another. To the Baldwins, your interest in, and enthusiasm for, my work has been a great encouragement throughout this process. Thank you very much. To my parents, your involvement in all of this is less concrete, but crucial just the same. What you’ve done, and been, for me belies description but underpins everything I do, including this work. Thank you. And finally to Caitlin, it’s been a great five years, let’s have many, many more! vii Abstract The two regimes of carbon nanotubes – wall and bore – provide two distinct environments. The extended pi structure of nanotube walls was used to transport electrons at energy levels dependent on the wall chirality. The empty bore was used to host solvent molecules and provide a pathway for proton transport. Simultaneous transport of both charged species was measured in a donor-‐acceptor system inspired by photosynthesis in plants and aimed at storing solar energy in chemical fuel. Transport was observed spectroscopically through use of indicator molecules. The interaction of solvent molecules in the bore with the confinement imposed by the walls was also probed by x-‐ray diffraction at low temperature. Confined molecules and their interactions have implications for areas as diverse as protein folding and geology. viii Contributors and Funding Sources Committee Professor Todd Krauss, Departments of Chemistry and Optics Professor Lisa DeLouise, Departments of Dermatology, Biomedical Engineering, and Electrical and Computer Engineering Professor Kara Bren, Department of Chemistry Chair Professor Hitomi Mukaibo, Department of Chemical Engineering Contributors Joanne Leadbetter assisted in the design and collection of voltage driven proton-‐crossing measurements described in Chapter 2. Fen Qiu synthesized the quantum dots used in Chapters 2 and 3. Anni Siitonen assisted in the development of the vertically aligned nanotube growth procedure described in Chapter 2. Steven Pilgrim assisted in the development of the epoxy impregnation method described in Chapter 2. Amanda Amori and Zhentao Hou performed the nanotube solubilizations and collected the spectroscopic information used to identify nanotube chirality described in Chapter 3. Michael Mark and Stephanie Daifuku built the Raman system used in some measurements in Chapter 3. ix Chae Un Kim and Sol Gruner assisted with collection of the x-‐ray diffraction patterns described in Chapter 4. Surendra (Vinnie) Gupta assisted with analysis of the powder diffraction patterns described in Chapter 4. All work mentioned above, with the exception of quantum dot synthesis, nanotube solubilization, and Raman system construction was carried out in direct collaboration with Greg Pilgrim, the author of this thesis. All other work described in this thesis was developed and carried out by Greg Pilgrim under the guidance of Todd Krauss. Funding Sources This work was funded by the U.S. Department of Energy. Significant portions of this work were performed at the Cornell Nanoscale Facility at Cornell University and at the Institute for Electronics and Nanotechnology at Georgia Institute of Technology, both of which are members of the National Nanotechnology Infrastructure Network supported by the National Science Foundation. Chapter 4 covers work performed at the Cornell High Energy Synchrotron Source at Cornell University, which is also supported by the National Science Foundation. x Table of Contents Dedication ii Biographical Sketch iii Acknowledgements v Abstract vii Contributors and Funding Sources viii Table of Contents x List of Tables xv List of Figures xvi List of Abbreviations xxxv Chapter 1: Introduction 2 1.1: Energy 2 1.1.1 Energy Consumption 2 1.1.2 Solar Power 2 1.1.3 Transportation Fuel 3 1.1.4 Solar Hydrogen 4 1.2 Artificial Photosynthesis 5 1.2.1 Background 5 1.2.2 Charge Separation 6 1.2.3 Water Splitting 9
Description: