SURFACE-ANALYSES OF PYROLYZED RICE HUSK USING SCANNING FORCE MICROSCOPY

Scanning force microscopy (SFM), also referred to as atomic force micr oscopy (AFM), has been used for the surface characterization of untrea ted and pyrolysed rice husk samples. This technique, unlike scanning e lectron microscopy, provides both qualitative and quantitative measure ments. The principles of SFM and sample preparation are discussed. Qua ntitative data in the form of surface roughness, void and fractal dime nsion are presented. The rice husks were pyrolysed in air at 573, 673 and 773 K for 30 min in a muffle furnace. The surfaces of the rice hus k pyrolysed at 773 K showed voids due to the decomposition of the orga nic matter. Quantitative analysis of these samples indicated that the surface roughness parameters decreased with increasing temperature owi ng to the increased decomposition of the organic matter. In addition, the number of voids and their z dimensions increased with increasing t emperature. The fractal dimension increased from 2.12 to 2.31 with inc reasing temperature, indicating that the voids were becoming rougher. Furthermore, the decomposition of the materials followed a fractal geo metry.