Homogeneous, circular Pt||ZrO nanoelectrodes have been synthesized through the sol-gel chemistry and the dip-coating process. These nanoelectrode arrays have been evaluated as a platform for electropolymerization of phenol, as model. We have shown that the microstructure of the polymer depends on the confined environment of the electrode and on the position of the -OH group of the monomer. Additionally, these nanoelectrodes have been tested as an electrochemical sensor for dihydroxybenzene isomers in aqueous medium. These Pt||ZrO nanoelectrodes exhibit a detection limit of 2 × 10 M for resorcinol and 1 × 10 M for catechol. [ABSTRACT FROM AUTHOR]