PREPARATION AND CHARACTERIZATION OF SOLID STATE IONIC MATERIALS
Dr. Rambabu Bobba
The primary focus of my research at Southern University has been centered in the area of preparation, synthesis and characterization of high temperature structural and solid electrolyte materials for device applications using non-destructive analytical techniques. Solid electrolytes have been successfully used for electrochemical devices such as sensors, batteries and fuel cells. We have studied a variety of materials in the past, including transition metal ions in alkali halide crystals, superionic conductors, fast ionic conducting glasses, and refractory metal suicides. We are developing " Materials Research Instrumentation Laboratory " in James Hall, Room Number 123 and 114. This laboratory is now equiped with FT-IR spectrometer, Fuel Cell workstation, battery testing unit, and Cyclic Voltametry equipment for material characterization. We are also anticipating funds to acquire Differential Scanning Calorimeter (DSC) and Thermogravemetric Analyser (TGA) very soon from Department of Defence.This laboratory is site for NSF_ARI project equipped UHV STM UV-VIS absorption and emission spectrometers.The NASA Microgravity Materials science program is considering to provide funds to build a crystal growth equipment to grow high temperature optical crystals in our laboratory. We are also involved in building the synchrotron radiation beamfine SEA institutions at Center for Advanced Microstructures and Devices (CAMD) and our Materials Research Instrumentation laboratory is the site for SEA researchers for the planning of experiments.
Our recent work on refractory metal silicides (AT&T TM 00324567,(1992), Sen-dcond. Sci. Tech. 8 (1993), and J. Elec. Mat. Vol. 22, No, 7, (1993)) has made a significant impact on the thermal processing of MOS devices and has lead to several industrial patents. Prior to the above work, we had made systematic investigations on the preparation and characterization of silver arsenate electrolyte glasses, and had studied the electrochemical performance of the solid state batteries (J. Mat. Sci, Vol. 26, 2451-2471 (1991), J. Mat. Sci. Letters. Vol. 9, 1066-1070 (1990), and J. Power Sources, Vol. 3 4, 3 3 9-3 5 2, (199 1)).
We aim at participating in the development of lithium polymer electrolyte battery technology for DOE-ELECTRIC VEHICLE 2000 program. Recent studies show that higher atomic elements such as Zn, Ni, etc., will also provide necessary characteristics to improve the performance of battery technology. We are now planning to investigate the electrochemical intercalation of cathode materials, and de-intercalation of lithium, zinc or nickel ions into transition metal oxide family such as VO 2 , MnO 2 , NiO 2 , CoO 2 and CuO 2 . The structural integrity of these electrolytes depend on their preparation conditions, original structure, cation valence state and the structural reorganization upon charge-discharge process. These materials will be prepared and characterized by the X-ray diffraction, X-ray Absorption Spectorscopy, UV_VIS-NIR and electron spectroscopic techniques.
We are also developing collaboration with DOW Chemical Company and Los Alamos National Lab to develop proton exchange membranes for high density fuel cells for transportation applications.
Research Projects: Click Here
Selected Publications: Click Here