Amna Kahn, Little Rock Central High School, Little Rock, AR
Mentor: Lee Conrad
Category: Energy and Transportation
Project Title: Defatted Soy as a High Performance Energy Storage Material for Super-Capacitors
Soybeans are the largest crops in Arkansas and therefore, its application in the energy sector is vital for the state’s economic health. Several soy-based materials (soy meal and defatted form of soymeal soy flour and soy protein) were examined as carbon-based energy storage materials for super-capacitors.
A prompt, low cost, single step, green and facile microwaveassisted process was utilized to prepare the carbonized materials. The concentration of doping elements (P and N) was altered by varying the mole ratio of ammonium polyphosphate (APP) in the reaction mixture. The un-doped and doped carbon materials of fatted and defatted soy samples were characterized both physically via BET, XPS and SEM analysis and electrochemically via cyclic voltammetry in both 1M H2SO4 and 6M NAOH. Pore size, surface area and elemental compositions of each material were analyzed to investigate the critical parameter of super-capacitor performance of the materials.
Furthermore, the capacitance of phosphorus and nitrogen co-doped carbon materials derived from soy samples were calculated and compared. Results suggest that the removal of fats from soy samples improves the capacitance of the materials. Among all materials, defatted soy protein doped with 0.8 g APP exhibited an exceptionally high surface area and high concentration of dope elements. Moreover, the hypothesis is supported that the removal of fat is essential to improve the conductivity of the substance which consequently impacts the specific capacitance of the material.