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Colloidal Electronics

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Colloidal Electronics Colloidal Electronics by (Albert) Tianxiang Liu B.S. Chemical Engineering, California institute of Technology, 2014 SUBMITTED TO THE DEPARTMENT OF CHEMICAL ENGINEERING IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY IN CHEMICAL ENGINEERING AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY July 2020 © 2020 Massachusetts Institute of Technology. All rights reserved. Signature of author ............................................................................................................................. Department of Chemical Engineering July 27, 2020 Certified by ........................................................................................................................................ Michael S. Strano Carbon P. Dubbs Professor of Chemical Engineering Thesis Supervisor Accepted by ....................................................................................................................................... Patrick S. Doyle Robert T. Haslam (1911) Professor of Chemical Engineering Graduate Officer 2 Colloidal Electronics by (Albert) Tianxiang Liu Submitted to the Department of Chemical Engineering on July 27, 2020, in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Engineering Abstract Arming nano-electronics with mobility extends artificial systems into traditionally inaccessible environments. Carbon nanotubes (1D), graphene (2D) and other low-dimensional materials with well-defined lattice structures can be incorporated into polymer microparticles, granting them unique electronic functions. The resulting colloidal electronic ‘cells’, comprised of microscopic circuits connecting artificial ‘organelles’ (e.g., generators, sensors, logic gates, etc.), combine the modularity of modern electronics with the characteristic mobility found in dispersive colloidal systems. Fundamental to colloidal electronics lie two challenges: (1) providing electrical energy to a microscopic system with limited footprint; and (2) developing energy efficient electronic devices and circuitries with low power consumption. In this context, my thesis introduces two concepts – Autoperforation and Asymmetric Chemical Doping – as means to fabricate and power electronic circuit elements on top of colloidal particles. These advances allow us to build the first colloidal electronic system that perform autonomous functions integrating energy harvesting, chemical detection and digital memory recording – all within a form-factor no larger than biological cells. Thesis Supervisor: Michael S. Strano, Carbon P. Dubbs Professor of Chemical Engineering 3 Acknowledgements I am forever grateful to have had Michael as my graduate advisor, who have continually fostered my scientific curiosity and encouraged my research independence. The extent to which his support has shaped my academic career cannot be overstated. Michael’s positivity, creativity, and scientific leadership have played a critical role in my growth as a scientist. I would like to thank Will Tisdale and Karthish Manthiram, for being a part of my Thesis Committee, for offering critical feedback at every step along the way, and for asking important questions to help me with my research and to steer me in the right direction. I would also like to thank Martin Bazant, Bill Deen, Jim Swan, Alan Hatton, and Klavs Jensen for their guidance and feedback on my thesis research. During my time at MIT, I have had many memorable moments as a teacher. I am grateful for the support of Bill Deen and Martin Bazant during my time as a TA for 10.50, of Klavs Jensen and Michael during my time as a TA for 10.65, of Michael during my time as a project consultant for 10.26, and Benjamin Hansberry for the Teaching Development Fellow program. I am extremely fortunate to have been surrounded by a group of talented colleagues within Michael’s group. I am particularly thankful to the help of Yuichiro Kunai, Anton Cottrill, Sayalee Mahajan, Pingwei Liu, Jingfan Yang, Ge Zhang, and Allan Brooks. I would also like to thank the students whom I have had a good fortune to work with: Stephen Gibbs, Jamila Smith- Dell, Max Saccone, Linh Nguyen, Rafid Mollah, Yannick Eatmon, Paul Baynard, Ian Timothy, and Lexy LeMar. 4 My thesis work has also greatly benefitted from a number of collaborators: Marek Hampel and Tomás Palacios from MIT, Ana Pervan and Todd Murphey from Northwestern, Paul McEuen from Cornell, Josh Daymude Andrea Richa from Arizona State, Dan Goldman and Dana Randall from Georgia Tech. I would also like to thank the following people who have helped me to navigate through career decisions: Michael, Karthish Manthiram, Connor Coley, Will Tisdale, Jim Swan, Bill Deen, Klavs Jensen, Kate Galloway, Ariel Furst, Crystal Chu, and Lennon Luo from MIT, Greg Fu, Mark Davis, John Seinfeld, Zhen-Gang Wang, and Max Saccone from Caltech, Ana Pervan and Todd Murphey from Northwestern, Josh Daymude from Arizona State, and Dana Randall from Georgia Tech. The past six years would not have been possible without my former scientific advisors: Jack Roberts, Greg Fu, Mark Davis, Stacey Zones, Steve Sieck, Jim Lindberg, Andy Mobley, and Heriberto Hernandez-Soto. These mentors have been, are, and will always be a source of inspiration. I can only hope to provide my own students with a small fraction of what they have provided me. I would not be where I am if it were not for my parents, Weimin Liu and Li Wang, and my partner, Stacey Fang. They have provided a tremendous amount of support in every way imaginable. For without their devotion, I would not have accomplished any of these, and without them, none of these accomplishments would have been meaningful. 5 Table of Contents Abstract ........................................................................................................................................... 3 Acknowledgements ......................................................................................................................... 4 Introduction to Colloidal Electronics .............................................................................................. 9 1.1 Colloidal State Machines: Autonomous Particles with On-Board Computation ........... 14 1.1.1 What are Colloidal State Machines? ....................................................................... 14 1.1.2 CSM Coagulation and Sedimentation ..................................................................... 17 1.1.3 Materials-Enabled CSM Modules........................................................................... 18 1.1.4 CSM Systems Integration ....................................................................................... 27 1.1.5 Control and Robotics of Autonomous CSMs ......................................................... 33 1.1.6 Application of CSMs .............................................................................................. 37 1.1.7 Conclusions and Outlook ........................................................................................ 40 1.2 Direct Electricity Generation Mediated by Molecular Interactions with Low Dimensional Carbon Materials – A Mechanistic Perspective .................................................. 42 1.2.1 Motivations for Solvent Mediated Energy Harvesting Methods ............................ 42 1.2.2 Mechanistic Overview ............................................................................................ 45 1.2.3 Perspectives, Application Space, and Energy Metrics .......................................... 112 1.3 References .................................................................................................................... 124 Sustainable Power Sources Based on High Efficiency Thermopower Wave Devices ............... 144 2.1 Background on Thermopower Wave Technology ....................................................... 145 2.2 High Efficiency Thermopower Wave Devices ............................................................ 146 2.3 References .................................................................................................................... 160 Electrical Energy Generation via Reversible Chemical Doping on Carbon Nanotube Fibers ... 163 3.1 Background on Excess Thermopower.......................................................................... 164 3.2 From Thermopower Wave to Asymmetric Chemical Doping ..................................... 166 3.3 Experimental Details .................................................................................................... 177 3.4 References .................................................................................................................... 179 Observation of the Marcus Inverted Region of Electron Transfer from Asymmetric Chemical Doping of Pristine (n, m) Single-Walled Carbon Nanotubes ..................................................... 182 4.1 Background on Asymmetric Chemical Doping ........................................................... 183 4.2 Asymmetric Chemical Doping Mechanism – an Electron Transfer Theory ................ 185 6 4.3 Experimental Details .................................................................................................... 203 4.4 References .................................................................................................................... 204 Solvent-Induced Electrocatalysis at an Asymmetric Carbon Interface ...................................... 207 5.1 Asymmetric Chemical Doping to Drive Electrochemical Transformations
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