Synthesis and properties of La_{1 – x}Sr_xNiO₃ and La_1–xSr_xNiO₂

Superconductivity has been realized in films of La$_{1-x}$Sr$_x$NiO$_2$. Here we report synthesis and characterization polycrystalline samples La$_{1-x}$Sr$_x$NiO$_3$ La$_{1-x}$Sr$_x$NiO$_2$ ($0\le x\le 0.2$). Magnetization resistivity measurements reveal that are paramagnetic metals exhibit insulating behavior. is not detected bulk The absence superconductivity may be due to the generation hydroxide during reduction or a small amount nickel impurities. effect interface also play role for superconductivity.