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Reactions of Graphene Oxide and Buckminsterfullerene in the Aquatic Environment Yingcan Zhao Purdue University

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Reactions of Graphene Oxide and Buckminsterfullerene in the Aquatic Environment Yingcan Zhao Purdue University Purdue University Purdue e-Pubs Open Access Dissertations Theses and Dissertations 8-2016 Reactions of graphene oxide and buckminsterfullerene in the aquatic environment Yingcan Zhao Purdue University Follow this and additional works at: https://docs.lib.purdue.edu/open_access_dissertations Part of the Environmental Engineering Commons Recommended Citation Zhao, Yingcan, "Reactions of graphene oxide and buckminsterfullerene in the aquatic environment" (2016). Open Access Dissertations. 896. https://docs.lib.purdue.edu/open_access_dissertations/896 This document has been made available through Purdue e-Pubs, a service of the Purdue University Libraries. Please contact [email protected] for additional information. Graduate School Form 30 Updated PURDUE UNIVERSITY GRADUATE SCHOOL Thesis/Dissertation Acceptance This is to certify that the thesis/dissertation prepared By Yingcan Zhao Entitled REACTIONS OF GRAPHENE OXIDE AND BUCKMINSTERFULLERENE IN THE AQUATIC ENVIRONMENT For the degree of Doctor of Philosophy Is approved by the final examining committee: Chad T. Jafvert Chair Timothy R. Filley Inez Hua Ronald F. Turco To the best of my knowledge and as understood by the student in the Thesis/Dissertation Agreement, Publication Delay, and Certification Disclaimer (Graduate School Form 32), this thesis/dissertation adheres to the provisions of Purdue University’s “Policy of Integrity in Research” and the use of copyright material. Approved by Major Professor(s): Chad T. Jafvert Approved by: Dulcy M. Abraham 6/21/2016 Head of the Departmental Graduate Program Date i REACTIONS OF GRAPHENE OXIDE AND BUCKMINSTERFULLERENE IN THE AQUATIC ENVIRONMENT A Dissertation Submitted to the Faculty of Purdue University by Yingcan Zhao In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy August 2016 Purdue University West Lafayette, Indiana ii To my parents and Liang, for their love, support and encouragement. iii ACKNOWLEDGEMENTS I would like to express my deepest gratitude to my Ph.D. major advisor, Prof. Jafvert, for his guidance, support and encouragement throughout my graduate research studies during the past few years at Purdue. Even though sometimes he is extremely busy, he would like to help me out with my hundreds of academic questions and difficulties. I also enjoy the academic freedom he gave me to explore my own interest in research. I have learned so much from him and if I have a chance to be faculty member in environmental engineering area in the future, I hope to be someone like you, Dr. Jafvert, patient, kind, generous and full of career passion. I want to further thank one of my committee members, Prof. Inez Hua, who provided me the opportunity to be a teaching assistant with her in Fall 2014 for the course CE/EEE 350 Introduction to Environmental Engineering. I cherish the whole semester working with her and five peer undergraduate TAs. I want to thank all my committee member: Drs. Chad Jafvert, Timothy Filley, Inez Hua and Ronald Turco. Without their guidance, this thesis would have been impossible to complete. I also want to thank Nadya Zyaykina, the environmental engineering laboratory manager. Thanks for her kindness and patience even though I bothered her so many times. I also would like to thank Prof. Zhi Zhou who provided instruments for iv my gel electrophoresis experiments and give me helpful suggestions when I applied for postdoc positions. I want to express my thankfulness to my lab mates: Somi, Hsin-Se, Tengyi, Ming, Xuda, Xuqing, Yining and Yichen; also Dr. Filley and his group: Tim Berry and Christy. I will cherish all your help and the time we spent together. Thanks to all my friends here at Purdue. You are like angels to make me feel we are just like a family. Although being so far away from home, my parents Honglai Zhao and Wenyan Zhang have never stopped offering me love and encouragement. Being their single child, I know I owe them a lot. Thanks for their support and love, forever. At the period of writing this thesis, I am excited to know that my husband and I will have our first baby soon. She gives me so much courage that keeps me moving on. I always wish to give her all the best things in life. Thank you for choosing us to be your parents and welcome to our home, my little sweetie. v TABLE OF CONTENTS Page LIST OF TABLES ................................................................................................................... vii LIST OF FIGURES .................................................................................................................. ix ABSTRACT .......................................................................................................................... xiii CHAPTER 1. INTRODUCTION ......................................................................................... 1 1.1 Scope and Significance ..................................................................................... 1 1.2 Fullerenes ......................................................................................................... 2 1.2.1 Physical and Chemical Properties of C60 ....................................................... 2 1.2.2 C60 Toxicity .................................................................................................... 3 1.2.3 C60 Photo-activity .......................................................................................... 4 1.3 Graphene Oxide ................................................................................................ 5 1.3.1 Graphene Oxide Applications ....................................................................... 6 1.3.2 Environmental Applications using Graphene Oxide-based Material ........... 7 1.3.3 Toxicity of Graphene Oxide........................................................................... 7 1.3.4 Environmental Transformation of Graphene Oxide ..................................... 8 1.3.5 High Electron Transfer Ability of Graphene Oxide........................................ 9 1.4 Chapter Outline .............................................................................................. 10 CHAPTER 2. ENVIRONMENTAL PHOtOCHEMISTRY OF SINGLE LAYERED GRAPHENE OXIDE IN WATER ............................................................................................................... 12 2.1 Abstract........................................................................................................... 12 2.2 Introduction .................................................................................................... 13 2.3 Materials and Methods .................................................................................. 17 2.3.1 Materials ..................................................................................................... 17 2.3.2 Preparation of Aqueous Graphene Oxide ................................................... 17 vi Page 2.3.3 Irradiation and GO Analysis ........................................................................ 18 2.3.4 ROS Measurement ...................................................................................... 19 2.4 Results and Discussion .................................................................................... 20 2.5 Conclusion ...................................................................................................... 30 2.6 Supporting Information .................................................................................. 32 CHAPTER 3. Light-IndepenDENT rEDOX REACTIONS OF GRAPHENE OXIDE IN WATER: ELECTRON TRANSFER FROM NADH TO MOLECULAR OXYGEN PRODUCING REACTIVE OXYGENM SPECIES (ROS) .................................................................................................. 37 3.1 Abstract........................................................................................................... 37 3.2 Introduction .................................................................................................... 38 3.3 Materials and Method .................................................................................... 40 3.3.1 Materials ..................................................................................................... 40 3.3.2 Oxidation of NADH ...................................................................................... 41 3.3.3 ROS Detection ............................................................................................. 41 3.3.4 Gel Electrophoresis ..................................................................................... 43 3.4 Results and Discussion .................................................................................... 43 3.5 Conclusion ...................................................................................................... 58 CHAPTER 4. INDIRECT PHOTO-TRANSFORMATION OF GRAPHENE OXIDE IN WATER 59 4.1 Abstract........................................................................................................... 59 4.2 Introduction .................................................................................................... 60 4.3 Materials and Methods .................................................................................. 63 4.3.1 Materials ..................................................................................................... 63 4.3.2 Irradiation of GO in Solar Spectrum Light ................................................... 63 4.3.3 Materials Analysis ......................................................................................
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