Polypyrrole (PPy) nanoparticles formed by chemical in situ polymerization were deposited on the hydrophilic/hydrophobic
surface of SiO2 substrates to give the diversely morphology, respectively. Themorphologies of PPy nanoparticles deposit were investigated using optical microscope, scanning electron microscope (SEM), and atomic force microscope (AFM) imaging techniques.The morphology of Y- and T-shape wrinkles was observed on the hydrophilic surface of SiO2 substrate, while the morphology of polygon-shape wrinkles on the hydrophobic surface of SiO2 substrate, and this distinction is due to the difference of the surface energy between the hydrophilic and hydrophobic surface of SiO2
substrate and so-called “memory effec