Mixed valence state and electrical conductivity of La1-xSrxCrO3

La1-xSrxCrO3 (x=0.0 similar to 0.5) samples were prepared by the sol-gel me thod. The crystal structures of La1-xSrxCrO3 at room temperature all are of the othorhombic perovskite GdFeO3-type. XPS analysis indicates that chromi um ions are in mixed valence state. The introduction of Sr2+ into the latti ce is compensated by the oxidation from Cr3+ to Cr6+ With x increasing, the amount of Cr6+ increases. The presence of the Cr6- is one of the key facto rs that affect the electric conductivity of La1-xSrxCrO3. (C) 2000 Elsevier Science S.A. All rights reserved.