Purity, Morphological, and Electrical Characterization of Silicon Dioxide from Cogon Grass (Imperata cylindrica) Using Different Ashing Temperatures

Cogon grass (Imperata cylindrica) was a detrimental plant and often found in the tropics which contains silicon dioxide. The objective of this study was to extract silicon dioxide from cogon grass and to study the purity, crystal structural, and electrical properties of silicon dioxide from cogon grass. The silica of cogon grass was extracted by washing dry cogon grass using 3% HCl before the burning process, and the ashing temperatures were 500°C, 600°C, and 700°C with a temperature increasing rate of 1°C/minute. The SEM-EDX results showed that silica of cogon grass has an irregular shape and a purity of 99.99%. the XRD results showed that silica has an amorphous phase with peaks at 2θ = 21-23°. The electrical analysis showed that the higher the ashing temperature led to the higher the conductance, the conductivity, and the dielectric constant on silica of cogon grass. Besides, the higher the frequency, the higher the electrical conductance and conductivity, but the lower the dielectric constant of silica. Based on the electrical conductivity, the silica of cogon grass was in the range of semiconductor materials.