Synthesis of Ruddlesden-Popper Type (La, Sr)_(n+1)V_nO_(3n+1)(n=1,2,3)

摘要

Perovskite-related layer compounds which consist of n units of the perovskite layers and a rock salt layer were prepared for n=1 and 3 in the system of (La, Sr)_(n+1)V_nO_(3n+1). Oxygen deficiency (#delta#) of LaSr_3V_3O_(10-#delta#) was determined to be 0.08 from a weight gain after the oxidation process. Lattice parameter of a- and c-axes of La_xSr_(4-x)V_3O_(10) (1<=x<=3) increased, respectively, from 0.3841 to 0.3896 nm for the a-axis and from 2.787 to 2.870 nm for the c-axis with a increase of x. Electric conductivity of the single layered compound, LaSrVO_4, was a semiconducting with #sigma#(RT)=3.37 S/cm. The triple layered compound, LaSr_3V_3O_(10-#delta#), exhibited a metallic conductivity with #delta#(RT)=93.7 S/cm, while highly doped LaSr_3V_3O_(10-#delta#) was a semiconducting. The electric conductivity #sigma#(RT) of La_xSr_(4-x)V_3O_(10) (1<=x<=3) decreased with increase of dopant concentrations.