A synthesis is described for Ru microelectrode arrays within a conductive Ti4O7 ceramic matrix. Data obtained by x-ray diffractometry and scanning electron microscopy are consistent with the existence of heterogeneous mixtures of Ru particles (ca. 0.8 mum diam) within the Ti4O7 matrices. No mixed metal oxides or other new compounds are detected. Rotated disk electrodes (RDEs) constructed from the Ru-Ti4O7 materials are compared on the basis of their voltammetric response for the oxidations of I- to I2 and IO3- in 0.10M H2SO4. These results are rationalized on the basis of microelectrode arrays, i.e., elevated current densities and diminished sensitivity to changes in rotational velocity compared with solid Ru RDE. An RDE constructed from Ru-Ti4O7 containing ca. 0.5% Ru by volume exhibits virtually zero dependence on rotational velocity for the oxidation of I- to I2 and, therefore, this material functions as an ideal microelectrode array