Rutile titanium dioxide (TiO2) (110) surfaces annealed in air were examined by frequency modulation atomic force microscopy (FM-AFM), X-ray photoelectron spectroscopy (XPS) and lowenergy electron diffraction (LEED) techniques. The terraces separated by monatomic steps showed an atomically irregular appearance in the obtained FM-AFM images, while the surface produced a (1 × 1) LEED pattern that indicated atomic ordering of the top few surface layers. Subsequent annealing in atmospheric-pressure O2 produced several ten-nanometre-sized pits with irregular shapes on the terraces. Molecule-sized spots were recognised on the subsequently O2-annealed surface. Half-order spots along the <001> directions emerged in the LEED pattern. We propose the rutile substrate covered with hydroxylated amorphous TiO2 of monatomic thickness as the structure of the air-annealed surface. The amorphous TiO2 was dehydroxylated by subsequent O2 annealing and was transformed into the thermodynamically stable rutile structure. The moleculesized spots were attributed to hydroxyl (OH) and hydroperoxyl (OOH) groups that were produced on the area with the (1 × 1) structure. A part of the OH and OOH groups were arranged in a (2 × 1) structure and produced the half-order spots in the LEED pattern.

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In recent years, considerable efforts have been made toward the control of processing techniques, volatile mass and component ratio of Potassium and Sodium in order to improve physical properties of KNN ceramics. In this paper, the influence of physical properties of the (KxNa1-x)NbO3 ceramics, fabricated using conventional solid state reaction method, on K/ Na component ratio was examined. The densities of ceramic sample changed depending on the variation of x parameter from 0.47 to 0.52 mol %. The highest value of density is 4.26 g/cm 3 at potassium content x of 0.48 mol %, coresponding with the uniform in microstructure of ceramic surface. Effects of K/ Na ratios in the vicinity of morphotropic phase boundary on microstructure, ferroelectric and piezoelctric properties are also examined. The (K0.48Na0.52)NbO3 system sintered at 1090 o C shows the highest values of remanent polarization Pr=3,19 C/cm 2 at the applied coercive electric field Ec=7,16 kV/cm. At x=0.48 mol %, electromechanical coupling factor kp of 0.26 and the piezoelectric constant d33 of 69 pC/N also can be obtained, related to homogenous grains size of orthohombic phase..