(180l) Unveiling the Electrochemical Potentials of Amino Acid-Derived Nitrogen Functionalized Magnetic Graphene

Using alternative energy devices has skyrocketed in the past couple of decades and is only increasing as more research is being put into the alternative energy field. Graphene is one of the most revolutionary materials discovered in the early 21st century and is a reason for this boom in alternative energy devices. Unfortunately, a couple of hurdles graphene presents for manufacturers to adopt commercially: high cost and material consistency. Hence, this study is focused on converting a common amino acid, L-glutamic acid, into nitrogen-functionalized graphene by a 2-step process in the presence of Iron (III) Nitrate to introduce magnetism of this novel graphene material. The synthesis starts with mixing L-glutamic acid and Iron (III) Nitrate in a 5:1 ratio (w/w) and then hydrothermally carbonized at 200℃ under a water medium to produce core-shell-type micrometer-sized spheres with carbon core and nitrogen and oxygen functional groups on the shell. The micro-sized spheres were then pyrolyzed at 1000, 1200, and 1400℃ under inert conditions to alter the amorphous carbon structure into a crystalline graphene structure with magnetic properties. The synthesized nitrogen-functionalized magnetic graphene (NMG) was characterized by X-ray diffraction for analyzing the crystal structure, Fourier transform infrared spectroscopy to detect functionality, elemental analyzer to measure the elemental composition, and Thermogravimetric Analysis to assess the thermal stability. Furthermore, galvanostatic charge/discharge was adopted for the NMG to evaluate the electrochemical properties. The crystallinity is verified by the X-ray diffraction results. Fourier transform infrared spectroscopy shows a correlation between temperature and functionality detection. Thermogravimetric Analysis shows that as the temperature of the graphitization step increases, the graphitized carbon becomes more thermodynamically stable. Overall, the graphitization step at 1000°C NMG displayed the highest specific capacitance (0.4914 C/g) at a current density of 0.2 A/g. Results show that specific capacitance decreases as temperature increases in the graphitization step for NMG. This study presents a novel synthesis of an amino acid into nitrogen-functionalized magnetic graphitic carbon with potential as an electrode material.