Superconductivity and ferromagnetism in Pd doped Y$_{\mathrm{9}}$Co$_{\mathrm{7}}$

The ferromagnetic superconductor Y$_{\mathrm{9}}$Co$_{\mathrm{7}}$ was chemically doped with Pd in an attempt to form Y$_{\mathrm{9}}$Co$_{\mathrm{7-x}}$Pd$_{\mathrm{x}}$ for 0\textless x\textless 0.4. The~lattice parameter $a$ does not depend on x; whereas, $c$ increases with increasing Pd content up to x $=$ 0.2, which turned out to be the palladium solubility limit. Superconductivity (T$_{\mathrm{sc}} \quad =$ 2.4 K) and ferromagnetism (T$_{\mathrm{C}} \quad =$ 4.5 K) were observed only for the parent Y$_{\mathrm{9}}$Co$_{\mathrm{7}}$ compound. For the lowest tested Pd doping level (x$=$0.05), strong enhancement of ferromagnetism is observed (T$_{\mathrm{C}} \quad =$ 9.35 K), but superconductivity is not seen above 1.8K. The Curie temperature rapidly increases from 4.5 K to about 10 K for a Pd concentration x$=$0.1 and remains almost unchanged for Y$_{\mathrm{9}}$Co$_{\mathrm{6.8}}$Pd$_{\mathrm{0.2}}$.