Synthesis and characterization of superconductor Bi3O2S3

• Layered superconductor Bi3O2S3 have been successfully prepared with Bi2O2S precursor.
• The zero resistivity transition temperature of bulk Bi3O2S3 is observed at 4.62 K.
• The susceptibility at 2 K is 0.031 emu Oe−1 g−1, indicating a perfect diamagnetism.

Bulk and nanoscale powder layered superconductor Bi3O2S3 have been successfully prepared via conventional solid-state reaction route. The diffraction peaks observed for Bi3O2S3, except for the small impurity peaks belong to Bi28O32(SO4)10, can be indexed to the orthorhombic (I4/mmm tetragonal) phase for Bi3O2S3 with cell constants a = 3.961 Å, c = 41.316 Å. The pill comprised of nanoscale Bi3O2S3 behaves like insulator. However the zero resistivity of bulk Bi3O2S3 is observed at 4.62 K. The superconductivity is also proved by the Meissner effect from the zero-field cooled and field cooled dc magnetization measurements, and the diamagnetic susceptibility which reflects shielding volume fraction of superconductor at 2 K is about −0.031 emu Oe−1 g−1, indicating a perfect diamagnetism.