（CaxSr1-x）TiO3的晶胞体积随Ca固溶量的增大而减少．XPS研究表明，虽然这种体积减少有使原子间结合能增大的趋势，但由于TiO6八面体的倾斜旋转，造成原子间键长加长，反而使得结合能有所降低．Ca的固溶会变化，导致晶界处化学环境的变化，使晶界吸附氧含量明显增大．（CaxSr1-x）TiO3优良的压敏特性归因于晶胞体积的收缩及化学势的变化.
(Ca_xSr1-x)TiO3 cell volume reduced with the increase of Ca content. This could lead to the increase of binding energy, but as shown by XPS analysis,
TiO6 octahedral tilted and made bonds longer, thus decreased the binding energy. This observation supported the point of Myhra. Ca-added could lead to the change of
chemical potential, and cause an increase of the oxygen adsorption at grain boundaries. The varistor behavior of (CaxSr1-x)TiO3 ceramics was caused by the
shrinking of cell volume and the change of chemical environment.
参考文献
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