Author: Bilia Momand Major: Chemistry & Biochemistry 

For the spring semester of 2020 I conducted research with Dr. Beyzavi in the chemistry department at the University of Arkansas. One research aim of Dr. Beyzavi’s lab is to construct Covalent Organic Frameworks (COF) as a tool for reaction catalysis. These COFs will allow certain reactions to proceed under conditions that normally would not be favorable. The goal of my research is to develop these COFs by a novel approach of layer-by-layer epitaxy, where the frameworks are built by adding one–molecule–thick layers at a time. This allows for greater precision for regulating the reaction sites of the COFs, which will provide the ability for even more reaction catalysis.  

The spring semester saw an unprecedented number of obstacles, both in and out of the research lab. In order for the COFs to be developed, synthesis and purification of numerous organic reagents needed to be performed. These starting reagents are synthesized in low yields due to their complex nature, so bulk synthesis of these compounds was completed first. In addition to preparing the starting compounds, I had to prepare the “base” with which the frameworks could be supported on. This involves a thin gold wafer which has a single layer of molecules that are capable of attaching to the starting compounds to begin developing the frameworks. For the first month of the semester, I was synthesizing and subsequently purifying the starting compounds as well as developing the gold wafer base for COF production. After numerous reactions, enough compounds were developed, and the production of the COFs was ready to begin.  

The next part of my research heavily relied on assistance from my mentor, Dr. Beyzavi, and the research team. In order for one layer of the framework to attach to the next, several linker molecules must be developed. A setback with these molecules is that controlling the position of several linkers with respect to each other is nearly impossible, making the connection of the single layers onto each other difficult to control. To overcome these challenges, the research lab designed and developed a robotic reactor (which I lovingly call “Janet”) that is capable of automating the reaction process so that the deposition of each layer of molecules can be repeated with precision hundreds of times. This automated system is essential for ensuring the repeatability and uniformity of single-layer molecule deposition for the frameworks. Operation of the robot requires supervision of either Dr. Beyzavi or a graduate student. Under their guidance, I was able to begin testing the approach of layer-by-layer COF synthesis. 

The preliminary findings were a mixture of positive and negative results. While single layer molecules were shown, the layers were scattered and not uniform on the gold wafer. In order to test the ability of these COFs for catalysis, a uniform single layer of molecules is needed. With these preliminary results, I went back to my starting reagents in order to change small aspects of the compounds in order to achieve the desired uniformity. After designing a new version of the starting compounds, I began another process of synthesis and purification.  

It was at this point in the semester that I received unfortunate news. Due to the events of Covid-19, the University and the department of chemistry research labs were closing for the safety of students and faculty. Whilst this was certainly a setback, I was determined to not let this stop my research. Working from home I searched through chemistry literature to find even more versions of the starting chemicals that possessed properties that I believe could enhance my goal of single-layer uniformity. During this time, I also communicated my interest to Dr. Beyzavi in allowing me to receive training to operate the automated system on my own, to which he agreed.  

Although the events of Covid-19 have provided a murky vision of what lies ahead, the goals of my research still stand bright. Once research labs are reopened, I will begin testing the new versions of starting compounds that I have found. Additionally, I will receive special training to operate the lab robot on my own, for the convenience of myself and those in the lab. Once I have characterized a uniform layer of molecules, I will test the COF’s ability for reaction catalysis in the fall semester.