Proceedings of the Forty-First DOE Solar Photochemistry P.I. Meeting Gaithersburg Marriott Washingtonian Center Gaithersburg, Maryland June 3-5, 2019 Chemical Sciences, Geosciences, and Biosciences Division Office of Basic Energy Sciences Office of Science U.S. Department of Energy FOREWORD The 41st Department of Energy Solar Photochemistry Principal Investigators’ Meeting, sponsored by the Chemical Sciences, Geosciences, and Biosciences Division of the Office of Basic Energy Sciences, is being held June 3-5, 2019 at the Washingtonian Marriott in Gaithersburg, Maryland. These proceedings include the meeting agenda, abstracts of the formal presentations and posters, and a list of participants. The Solar Photochemistry Program supports fundamental, molecular-level research on solar energy capture and conversion in the condensed phase and at interfaces. This conference is the annual meeting of the grantees who conduct research with support from this Program. The gathering is intended to facilitate the exchange of ideas and foster collaboration among these researchers. The meeting this year features an invited presentation by Harry Atwater, Director of the Joint Center for Artificial Photosynthesis (JCAP). JCAP is the Department of Energy’s Fuels from Sunlight Energy Innovation Hub, a multi-investigator research and development center that was established in 2010 and renewed in 2015. Its mission is currently focused on creating a scientific foundation for the solar-driven conversion of carbon dioxide into renewable transportation fuels. Prof. Atwater will tell us about recent JCAP discoveries and research accomplishments. I would like to express my thanks to Justin Johnson who continues to spend part of his time as a detailee for the Solar Photochemistry Program, assisting with numerous critical behind-the- scenes tasks. Special appreciation also goes to Teresa Crockett of the Office of Basic Energy Sciences and Connie Lansdon of the Oak Ridge Institute for Science and Education for their assistance with logistics for this meeting. Finally, I am grateful to all of the participants in this meeting who have contributed so much to the continued success of the Solar Photochemistry Program. Chris Fecko Chemical Sciences, Geosciences, and Biosciences Division Office of Basic Energy Sciences ii TABLE OF CONTENTS Foreword ........................................................................................................................................ ii Program ....................................................................................................................................... xii Abstracts of Oral Presentations Session I – Opening Session Pathways to Selective and Efficient Carbon Dioxide Reduction Harry A. Atwater .................................................................................................................1 Session II – Electron Transfer and Proton-Coupled Electron Transfer A Bigger, Better Inverted Region John R. Miller, Richard A. Holroyd, Andrew R, Cook, Norihiko Takeda, Tomoyasu Mani, Marshall D. Newton, Matthew J. Bird, and Hung-Cheng Chen................................3 Proton-Coupled Electron Transfer Drives Grotthuss-Type Proton Transfer in Artificial Photosynthesis Devens Gust, Thomas A. Moore, and Ana L. Moore ..........................................................6 Hydrogen Bonding Interactions in Photoinduced PCET Dmitry E. Polyansky, Sergei V. Lymar, Mehmed Z. Ertem, and Gerald F. Manbeck ........8 Session III – Molecular Chromophores and Catalysts Model Dyes for Study of Electron Transfer Processes at Metal Oxide Semiconductor Interfaces E. Galoppini, R. A. Bartynski, L. Gundlach, A. Teplyakov, R. Harmer, H. Fan, S. Rangan, J. Vierek, J. Nieto-Pescador, and B. Abraham ....................................................11 Molecular Modules for Photochemical and Catalytic Function in Artificial Photosynthesis Karen L. Mulfort, Lars Kohler, Dugan Hayes, Ryan G. Hadt, Jens Niklas, Oleg G. Poluektov, Lin X. Chen, and David M. Tiede ...................................................................14 Aryl Ether Weak Donor-Based Dyes as Strong Photoinduced Oxidants Roberta R. Rodrigues, Adithya Peddapuram, and Jared H. Delcamp ...............................17 iii Session IV – Supramolecular Assemblies Photoacid Dye-Sensitized Solar Energy Conversion using Water as a Protonic Semiconductor Leanna Schulte, Simon Luo, Rylan Kautz, Joseph Cardon, William White, and Shane Ardo ...................................................................................................................................18 Organic, Nanoscale, and Self-Assembled Structures Relevant to Solar Energy Conversion Michael J. Therien .............................................................................................................20 Microsecond Charge Separation Lifetimes in Semiconducting Single-Walled Carbon Nanotube Heterojunctions Jeff Blackburn, Hyun Suk Kang, Dana Sulas, Andrew Ferguson, Justin Johnson, and Garry Rumbles ...................................................................................................................23 Session V – Singlet Fission and Triplet Dynamics Ultrafast Vibrational Nano-Thermometers to Probe Triplet Separation vs. Relaxation during Singlet Fission Eric R. Kennehan, Grayson S. Doucette, and John B. Asbury ..........................................28 Triplet Energy Transduction in Designed Chromophore Architectures Melissa K. Gish, Nadia V. Korovina, Marissa Martinez, Natalie A. Pace, Nicholas Pompetti, Matthew C. Beard, and Justin C. Johnson .........................................................32 Singlet Fission in Nanocrystal-Molecule Hybrid Structures Zhiyuan Huang and Ming Lee Tang ..................................................................................36 Quantum Interferences among Dexter Energy Transfer Pathways Shuming Bai, Peng Zhang, Spiros S. Skourtis, and David N. Beratan ..............................38 Session VI – Bioinspired/Biohybrid Approaches Modular Nanoscale and Biomimetic Assemblies for Photocatalytic Hydrogen Generation Kara L. Bren, Todd D. Krauss, and Ellen M. Matson .......................................................40 Photochemical N2 Reduction by Nanoparticle-Nitrogenase Complexes Katherine A. Brown, Jesse Ruzicka, Hayden Kallas, Bryant Chica, David W. Mulder, John W. Peters, Gordana Dukovic, Lance C. Seefeldt, and Paul W. King ........................43 iv Session VII – Semiconductor Nanoparticles for Solar Energy Conversion Controlling the Optical and Electrical Properties of QDs, QD assemblies, and QD Films for Solar Energy Conversion Daniel Kroupa, Haipeng Lu, Noah Bronstein, Yong Yan, Nathan Neale, Elisa Miller, Mike Carroll, Marissa Martinez, Arthur J. Nozik, Justin C. Johnson, and Matthew C. Beard ..................................................................................................................................45 Hot-Carrier Dynamics in Quantum Dots Manipulated by Spin-Exchange Auger Interactions Rohan Singh, Wenyong Liu, Jaehoon Lim, Istvan Robel, and Victor I. Klimov ..............50 Time-Domain Atomistic Studies of Far-from-Equilibrium Dynamics in Nanoscale Materials for Solar Energy Harvesting Oleg V. Prezhdo .................................................................................................................52 Metal-Tipped and Electrochemically Wired Semiconductor Nanocrystals: Modular Constructs for Directed Charge Transfer Jeffry Pyun, S. Scott Saavedra, and Neal R. Armstrong ....................................................57 Session VIII – Semiconductor Photoelectrodes Modulation of Photoinduced Charge Transfer at the Semiconductor Interface Rebecca Scheidt, Elizabeth Kerns, Greg Samu, and Prashant V. Kamat ..........................59 Molecular Level Functionalization, Atomically Thin Photoelectrodes, and Protective Coatings Based on Two-Dimensional Materials Ellen X. Yan, Annelise C. Thompson, Burton H. Simpson, Miguel A. Cabán-Acevedo, Kimberly M. Papadantonakis, Bruce S. Brunschwig, and Nathan S. Lewis .....................63 Photoexcited Charge Carrier Dynamics at Photocatalytic Semiconductor/liquid Interfaces Zed Xu, Haotian Shi, Bingya Hou, Fengyi Zhao, Tim Lian, and Stephen B. Cronin .......65 Investigating Ultrafast Dynamics in Solid-State Photocatalytic and Photovoltaic Materials Using Time-Resolved Mössbauer Spectroscopy Cali Antolini, Melissa A. Smith, Jacqueline Escolastico, Nathan Girard, Xiaoyi Zhang, E. Ercan Alp, Benjamin T. Young, and Dugan Hayes ......................................................67 Session IX – Heterogeneous Solar Fuels Catalysts Tracking Structures in Solar Fuels Catalysis: In-situ X-ray Characterization of Interfacial Water-Splitting Molecular and Thin-Film Catalysts David M. Tiede, Gihan Kwon, Alex B. F. Martinson, Tae Wu Kim, Emily Sprague- Klein, Karen L. Mulfort, Oleg G. Poluektov, and Lin X. Chen .......................................69 v Nanoscale Probing of Carrier-Selective Catalyst-Semiconductor Contacts in Water- Splitting Photoelectrodes Shannon W. Boettcher, Forrest Laskowski, Michael Nellist, Jingjing Qui, Sebastian Oener, and Adrian Gordon .................................................................................................72 Proton-Coupled Electron Transfer Studies of Homogeneous and Heterogeneous Energy Conversion Catalysts Daniel G. Nocera ...............................................................................................................75 Session X – Building Systems for