Mesoporous Manganese Oxide Materials for Aerobic Oxidation Reactions

166 Pages·2016·10.8 MB·English

by  Sourav Biswas

University of Connecticut
OpenCommons@UConn
Doctoral Dissertations University of Connecticut Graduate School
9-8-2016
Mesoporous Manganese Oxide Materials for
Aerobic Oxidation Reactions
Sourav Biswas
[email protected]
Follow this and additional works at:https://opencommons.uconn.edu/dissertations
Recommended Citation
Biswas, Sourav, "Mesoporous Manganese Oxide Materials for Aerobic Oxidation Reactions" (2016).Doctoral Dissertations. 1202.
https://opencommons.uconn.edu/dissertations/1202
Mesoporous Manganese Oxide Materials for Aerobic Oxidation
Reactions

Sourav Biswas, Ph.D.

University of Connecticut, 2016

The thesis presented here is focused on fabricating thermally stable and tunable mesoporous
manganese oxide materials for catalytic aerobic oxidation reactions. From the viewpoint of green
chemistry, the design of novel methodologies for oxidation, preferably under aerobic atmospheric
condition, without any additives is highly desirable. Being motivated by advances in catalytic
materials as fundamental pillars of ‘green chemistry’, my research is devoted to designing of useful
materials in oxidative catalysis that may serve the purpose of sustainable energy sources in
harmony with the environment and nature. The five chapters provided here will discuss the
importance of catalytic oxidation reactions, synthesis, and characterization of the mesoporous
manganese oxide materials and their applications in a series of simple to complex oxidation
reactions. We demonstrate the activity enhancement of mesoporous manganese oxide materials by
introducing alkali metal ions in a simple alcohol oxidation reaction. The major achievement of this
work is inventing a cesium ion promoted mesoporous manganese oxide, which was found to be
active in a multitude of aerobic oxidation reactions. In terms of catalytic oxidation reactions,
oxidation of alcohol to aldehydes, amines to imines, a versatile one –pot tandem oxidation
processes and oxidative coupling of alkynes have been discussed. Moreover, mechanistic aspects
of catalytic oxidation are studied in details, especially the role of the surface oxygen species,
i
oxygen vacancies and related oxygen transportation of the metal oxides. The catalytic oxidation
protocols discussed here have several advantages over the existing systems in addressing the goals
of green chemistry. First, the heterogeneous nature of the catalyst provides ease of separation of
product. Next, excellent reusability of the catalyst (as high as 8 cycles) and formation of water as
the only by-product (in most of the cases) reduces toxic waste production. Finally, absence of
additives and use of air as the terminal oxidant exemplify the greener, more efficient and less
expensive nature of these processes.

ii
Mesoporous Manganese Oxide Materials for Aerobic Oxidation
Reactions

Sourav Biswas

B.Sc., Jadavpur University, Kolkata, India. 2008
M.Sc., Indian Institute of Technology, Madras, India. 2011

A Dissertation
Submitted in Partial Fulfillment of the
Requirement for the Degree of
Doctor of Philosophy
at the
University of Connecticut
2016

iii
Copyright by
Sourav Biswas, 2016. All rights reserved.

2016
iv
v
Dedicated to my parents, my brother and my beloved wife

vi
Acknowledgements

I would like to express my sincere gratitude to my major advisor, Dr. Steven L. Suib, for
his guidance and constant support throughout my graduate career. The opportunity to work on a
wide range of projects and interaction with diverse group of people in his research group allowed
me not only to broaden my knowledge of chemistry but also made me a well-rounded person. The
most important things I learned from him are the dedication and enthusiasm to work, which will
stay with me in the rest of my life.
I would like to thank my associate advisors Dr. Amy R. Howell, Dr. Alfredo Angeles-
Boza, Dr. Ramamurthy Ramprasad and Dr. Fatma Selampinar for their support and guidance.
I would also like to express my thanks and gratitude to Dr. Partha Nandi, Mrs. Bonnie
Segundo Suib, Dr. Angelo R. Rossi, and Dr. Frank Galasso for their guidance, support and
encouragement. I am very thankful to my colleagues and group members Dr. Chung-Hao Kuo,
Sheng-Yu Chen, Curtis Guild, Biswanath Dutta, David Kriz, Ehsan Moharreri, Islam Mosa, Anton
Gudz, Dr. Abdelhamid El-Sawy, Dr. Lakshitha Pahlagedara, MD Shakil, Saiful Seraji, Wenqiao
Song, Junkai He, Wei Zhong, Niluka Wasalathanthri, Chandima Weerakkody, Carlos Mendoza,
Hannah Trip, David Giori, Tehereh Jafari, Harshul Khanna and especially Dr. Altug S. Poyraz.
I am grateful to the Department of Chemistry and Institute of Materials Science, University
of Connecticut and their employees for their support during my graduate studies. Special thanks
to Dr. You-Jun Fu, Dr. Heng Zhang, Dr. Bill Willis, Dr. William A. Hines, Osker Dabahsu,
Charlene Fuller, and Ashley Orcutt for their assistance.
I acknowledge the financial support of the United States Department of Energy, Office of
Basic Energy Sciences, and the Department of Chemistry, the Institute of Materials Science, the
vii
Center for Environmental Sciences and Engineering, and the Graduate School of the University of
Connecticut.
I also want to thank my mom, dad and my brother for their sacrifice and continuous support.
Without the help of them, I cannot have such a life here. Lastly I would like to express my heartiest
gratitude to my wife Mrs. Kankana Mullick. She has played a pivotal role in my life and without
her support and unconditional love I would not be the person I am today.

viii
Table of Contents

Chapter 1. Introduction
1.1 Overview of Catalytic Oxidation ..............................................................................................1
1.2 Heterogeneous Catalysts …………………………...................................................................2
1.3 Mesoporous Materials................................................................................................................2
1.4 UCT Materials............................................................................................................................4
1.5 Manganese Oxides .....................................................................................................................6
1.6 References ................................................................................................................................8

Chapter 2. Ion Induced Promotion of Activity Enhancement of Mesoporous Manganese
Oxides for Aerobic Oxidation Reactions
2.1 Abstract ...................................................................................................................................11
2.2 Background and Significance ……………………………………………..............................11
2.3 Experimental Section ...............................................................................................................13
2.3.1 Synthesis of UCT-1 ..........................................................................................................13
2.3.2 Synthesis of UCT-18 .......................................................................................................14
2.3.3 Catalyst Characterization .................................................................................................14
2.3.4 Catalytic Activity Measurement ......................................................................................16
2.4 Structural Characterization ……………………………..........................................................17
2.5 Catalytic Reactions ..................................................................................................................25
2.5.1 Catalyst Screening ............................................................................................................25
2.5.2 Oxidation of Alcohols ......................................................................................................27
2.5.3 The oxidation of 1,3,5-trimethylbenzene (C-H activation)................................................29
2.6 Discussions ..............................................................................................................................30
2.7 Conclusions .............................................................................................................................35
2.8 References ..............................................................................................................................37
ix