Effect Of Excess Bi And S On The Synthesis Of Bi4o4s3 Superconductor

We present the synthesis and discussion on results of Bi4O4S3 synthesized with excess Bi and S. As the melting points of Bi and S are 270 degrees C and 110 degrees C, i.e., less than the processing temperature of Bi4O4S3 (510 degrees C), there is a possibility for off- stoichiometry of Bi and S in Bi4O4S3 due to evaporation of Bi and S. Sample with 10% of excess Bi and S in addition to the stoichiometric ratio were prepared through solid state reaction method and named as BiOS-4. The comparative results of stoichiometric sample (BiOS-1) and Bi4O4S3 sample synthesized with excess Bi and S (BiOS-4) are presented. Excess bismuth and sulfur resulted in suppression of superconducting phase volume fraction in Bi4O4S3.