ENG
INA
81st Doctoral Promotion
Promovenda Ir. Ni Made Dwidiani, MASc, passed her doctoral dissertation and became the 81st PhD in the Study Program of Doctoral Engineering Science (PSDIT). The dissertation titled Synthesis and Characterization of Carbon Nanomaterials Using Bio-Activators and Rice Husk Precursors received a very satisfactory predicate.
Dr. Ir. Ni Made Dwidiani, MASc investigates the synthesis and characterization of semiconductor materials derived from rice husks that are biologically activated with pineapple peel juice, thereby presenting an environmentally friendly and sustainable approach. This research produces organic photoactive semiconductor materials from rice husk ash (RHA). RHA is activated by soaking it in a pineapple peel juice solution. Distinct structural differences between RHA, Sunken Carbon nanomaterial (SCNM), and Floating Carbon Nanomaterial (FCNM) materials are revealed through SEM imaging, showing the tailored properties of each material. SEM images also show the role of bromelain from pineapple juice in providing defects on the RHA carbon surface. Cracks in the nanoparticles on the surface of SCNM and FCNM are formed due to the electrostatic interaction of bromelain with the surface. Elemental analysis shows a higher probability of the presence of CuO and Si in SCNM, indicating its potential for semiconductor extraction. The Cu to Si ratio shows photoactivity, confirmed by UV-Vis characterization showing absorption peaks in the UV region. FTIR analysis highlighted increased polar interactions in SCNM and FCNM, which was caused by an activation process involving bromelain in pineapple juice. Photoelectric effect testing shows FCNM and SCNM produce more electric current when exposed to light. This current is generated due to the phenomenon of electron transport containing CuO and Si, which is triggered by photons. This study provides insight into the material's molecular structure and potential applications in sensors, energy devices, and semiconductor-related technologies, leveraging the unique properties of bio-derived nanomaterials for practical implementation. The promoter, co-promoters I and II, are Prof. Ir. Ngakan Putu Gede Suardana, M.T., Ph.D, IPU., Prof. Ir. I.N.G. Wardana. M.Eng. PhD., and Prof. Dr. Ir. I Gusti Ngurah Nitya Santhiarsa, M.T, respectively.
FACULTY OF ENGINEERING