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NOVEL ENVIRONMENTAL and EXPLOSIVES DETECTION APPLICATIONS for MOLYBDENUM OXIDES by KEVIN NAKIA BARBER Bachelor of Science in Ch

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NOVEL ENVIRONMENTAL and EXPLOSIVES DETECTION APPLICATIONS for MOLYBDENUM OXIDES by KEVIN NAKIA BARBER Bachelor of Science in Ch NOVEL ENVIRONMENTAL AND EXPLOSIVES DETECTION APPLICATIONS FOR MOLYBDENUM OXIDES By KEVIN NAKIA BARBER Bachelor of Science in Chemical Engineering University of Oklahoma Norman, Oklahoma 1999 Master of Science in Chemical Engineering Oklahoma State University Stillwater, Oklahoma 2005 Submitted to the Faculty of the Graduate College of the Oklahoma State University in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY July, 2009 NOVEL ENVIRONMENTAL AND EXPLOSIVES DETECTION APPLICATIONS FOR MOLYBDENUM OXIDES Dissertation Approved: Dr. Allen W. Apblett Dissertation Adviser Dr. Nicholas Materer Dr. Jeffery White Dr. Legrande Slaughter Dr. John Veenstra Dr. A. Gordon Emslie Dean of the Graduate College ii ACKNOWLEDGMENTS If I were to thank everyone individually who helped make this work possible in both large and small ways this acknowledgements section would be larger than the dissertation itself. I especially thank Dr. Allen Apblett for all of his instruction, his patience, his advice, and especially his friendship over these last four years. He is a man I have learned a great deal from, have a great deal of respect for, and would do well to emulate. I also thank Dr. Nicholas Materer for all his help with these projects I have worked on, for his help with the XPS data, for his advice and (always constructive) criticism, and for his friendship. I thank my committee members: Dr. Legrande Slaughter who was my first instructor in this department when I took his Graduate Inorganic Chemistry course for my technical elective in engineering; Dr. Jeffery White who taught me heterogeneous catalysis; Dr. John Veenstra, with whom I also worked in my engineering studies. I also thank the rest of the faculty and staff of the Chemistry Department, including, but definitely not limited to, Drs. Ohrtman and Iob with whom I have worked in the teaching labs. Drs. Berlin, Raff, and Bunce who were always willing to advise me and answer questions. I thank Alan Piquette for all of his assistance with and training on the various instrumentation and equipment and his patience therein. I thank Dane Scott who was always to cheerfully willing lend a hand. I thank Cory Perkins for all of his help and his many hours of hard work assisting me with the statistically designed experiments associated with the aqueous synthesis of the sodium hydrogen molybdenum bronzes. I thank the rest of our research group for their assistance and friendship. I also thank Dr. Charlotte Ownsby for her help with the scanning and transmission electron microscopes, Dr. Shushing Tan for teaching me to operate the atomic force electron microscope, and Terry Colberg for his assistance in preparing samples. I thank my family for all their love, help, and faith in me: My father and mother Charles and Juanita Barber who have helped me so much and taught me by example; my aunt Betty Maggard Elliot who has supported me in all things; my uncle Dale Maggard, who has passed on, who taught me to fix televisions; my grandmother, Mrs. Cammie Virden, who has also passed on, who taught me to read, write, add, and subtract, the ultimate foundations of this work, when I was still nearly a baby; my cousin Tammy Duvall Parks, who’s more like a sister than a cousin, who has always supported me (and defended me when necessary). iii I thank all of my friends including, but not limited to, Ronetta Kerntke and her family, Louis Rose, Mark Deaver, Joe Hurdle, Wei (George) Liu, Dr. Jerry Newman, and many others for all of their support, their friendship, and keeping me relatively sane over the years. In due humility I must also thank God for the opportunities that I have been given, the good people who I’ve met which have been such a help to me, my health and natural abilities, my good fortune in general, and other blessings too numerous to mention here. I owe a lot of people for their assistance in making me a scientist, and I have a lot of good examples to live up to. I intend to do my best to make you all proud and bring honor to my instructors and to my alma mater . iv TABLE OF CONTENTS Chapter Page I. INTRODUCTION ......................................................................................................1 AIM OF STUDY .....................................................................................................1 INTRODUCTION ...................................................................................................4 Structure and Properties of Molybdenum Bronzes .............................................4 Electronic Band Structure of the Molybdenum Bronzes ..................................18 Synthesis of Hydrogen Molybdenum Bronzes .................................................20 Synthesis of Alkali Metal Bronzes ...................................................................24 Applications of the Molybdenum Bronzes .......................................................38 CONCLUSION ......................................................................................................42 II. SYNTHESIS AND CHARACTERIZATION OF MOLYBDENUM OXIDE BRONZES .............................................................................................................43 INTRODUCTION .................................................................................................43 EXPERIMENTAL .................................................................................................44 Synthesis of Proton Bronze by Dissolving Metal Reduction............................44 Synthesis of Proton Bronze by Reduction of Molybdenum Trioxide with Sodium Dithionite ........................................................................................46 Synthesis of the Sodium Molybdenum Bronze via Dithionite Reduction in Aqueous Media ........................................................................................47 Synthesis of the Sodium Molybdenum Bronze via Dithionite Reduction in Ethanolic Media .......................................................................................49 Assay of the Purity of the Sodium Dithionite via Iodometric Titration ...........49 Determination of the Sodium Content of the Bronze Products ........................53 RESULTS AND DISCUSSION ............................................................................58 Hydrogen Molybdenum Bronze Products ........................................................58 Synthesis of Proton Bronze by Reduction of Molybdenum Trioxide with Sodium Dithionite ............................................................................................62 Aqueous Sodium Molybdenum Bronze Products .............................................66 Ethanolic Sodium Molybdenum Bronze Products ............................................73 CONCLUSIONS....................................................................................................76 ACKNOWLEDGEMENTS ...................................................................................78 v Chapter Page III. NANOPARTICULATE PHASE CHARACTERISTICS, COLORIMETRY, AND EXPLOSIVE SENSING APPLICATIONS OF SODIUM MOLYBDENUM BRONZE................................................................................................................79 INTRODUCTION .................................................................................................79 EXPERIMENTAL .................................................................................................81 Preparation of Sodium Bronze Solution ...........................................................81 Determination of the Concentration of the Sodium Bronze Solution ...............82 Determination of Reducing Capacity of Solutions ...........................................84 Particle Size Analysis .......................................................................................85 Reaction of the Sodium Bronze Solution with the Chlorine (Trichloro-s- triazinetrizone) Solution................................................................................86 Reaction of Sodium Bronze Test Strips with Hydrogen Peroxide ...................87 Reaction of Sodium Bronze Solution with Sodium Chlorate ...........................87 Electronic Detection of Peroxide Vapor Using Sodium Bronze-Vycar Material .........................................................................................................87 RESULTS AND DISCUSSION ............................................................................88 Determination of Chlorine Concentration ........................................................90 Detection of Peroxide Using Sodium Bronze Test Strip ..................................91 Detection of Chlorates Using Sodium Bronze Solution ...................................93 Electronic Detection of Peroxide Vapor Using Sodium Bronze-Vycar Material .........................................................................................................93 CONCLUSIONS....................................................................................................94 IV. REMOVAL OF HEAVY METAL CATIONS FROM WATER USING MOLYBDENUM OXIDE BRONZES ..................................................................96 INTRODUCTION .................................................................................................96 EXPERIMENTAL .................................................................................................98 Materials ...........................................................................................................98 Analyses
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