Superconductivity in (Hg,Mo)Sr2CuO4+δ system

The 1201-type Hg–Sr-based cuprates with nominal composition of (Hg1−xMox)Sr2CuO4+δ; x=0.15, 0.25 and 0.30, were prepared in partial vacuum. XRD data confirms that they are 1201-type structure. The ac-susceptibility measurements of the samples show that for the composition x=0.15 has a maximum Tconset of ∼66 K, while x=0.25 exhibits Tconset of ∼50 K. For x=0.30, the observed Tconset of ∼36 K is at variance with that reported in literature.