  By using solid state reaction method, we have synthesized the Pd-doped
superconductor SrFe2-xPdxAs2. The systematic evolution of the lattice constants
indicated that the Fe ions were successfully replaced by the Pd. By increasing
the doping content of Pd, the antiferromagnetic state of the parent phase is
suppressed and superconductivity is induced at a doping level of about x=0.05.
Superconductivity with a maximum transition temperature Tc of about 8.7 K was
achieved at the doping level of x = 0.15. The general phase diagram of Tc
versus x was obtained and found to be similar to the case of Ni and Co doping
to the Fe sites. Our results suggest that superconductivity can be easily
induced in the FeAs family by adding electrons into the system, regardless with
the transition metals of 3d or higher d-orbital electrons.
