ATOMIC-FORCE MICROSCOPY AND UV-VISIBLE ABSORPTION-SPECTROSCOPY STUDIES OF ZNO NANOMETER COLLOIDAL PARTICLES SUPPORTED ON GRAPHITE

ZnO nanometer particles were synthesized by depositing ZnO colloidal s uspensions onto the substrate of Highly Oriented Pyrolytic Graphite (H OPG). The isolated particles and their aggregation phase were directly imaged by Atomic Force Microscopy (AFM). High-resolution AFM images h ave been used to measure the diameter of individual particles, and lar ge area images revealed that these ZnO particles on graphite surface f orm netlike aggregation. Experimental results also indicated that disp ersive particles on a flat area are very mobile and easy to be pushed around during scanning due to the their weak adsorption on the substra te and tip-particle interactions.