CRYSTAL STRUCTURE AND MAGNETIC PROPERTIES OF NANOPARTICLES BSCNGCO SUPERCONDUCTORS AT ROOM - TEMPERATURE

Abstract

Synthesis of nano-particles Bi2Sr2(Ca1,5Nd0,25Gd0,25)Cu3Oz (BSCNGCO) superconductorshas been successfully done by the wet mixing method. The aim of the study was to produce nanoparticles ofBSCNGCO superconductors and study magnetic properties at room temperature. In this research, the rawmaterial used in the formation of BSCNGCO superconductors is Bi2O3 (99.9%), SrCO3 (99.9%),CaCO3 (99.9%), CuO (99.9%), Nd2O3 (99.9%) and Gd2O3 (99.9%). The synthesis process was conductedby added with HNO3 and mixing by a magnetic stirrer to obtain a homogeneous solution, then continuedwith the calcination process at 450oC for 2 hours and 600oC for 1 hour. The sintering process is done at830oC with a variation of time, that is 10, 20 and 30 minutes. The result of XRD characterization isdominated by BSCNGCO with 2223 phases and BSCNGCO with 2212 phases, but there are still impuritiesin each sample such as Bi2CuO4 and Bi2O2.7. The addition of sintering time in 10, 20 and 30 minutesresulted in the addition of fractional volume values of BSCNGCO with 2223 phases, respectively 42.39%,47.85%, and 49.42%. In contrast, the fraction of the phase volume of impurities (Bi2CuO4, BSCNGCO with2212 phases, Bi2O2,7) decreases with the addition of sintering time. From the results of TEM morphologyand calculations using the Scherrer equation, we can determine the particle size of sample superconductors.The addition of sintering time in 10, 20 and 30 minutes resulted in increased particle size, respectively 25.61nm, 26.10 nm and 30.08 based on calculations using the Sherrer equation. While the calculations using theImageJ program of the TEM results of 0.2 nm and 0.5 nm, for the sintering time of 10 and 20 minutesrespectively. The results of the VSM characterization of the sample exhibit ferromagnetic properties at roomtemperature. The addition of sintering time causes the saturation magnetization (Ms), a remanentmagnetization (Mr) and coercive force (Hc) values to decrease. Samples of superconductors with sinteringtime of 10 and 20 minutes showed Ms values of 0.155 emu/g and 0.157 emu/g, Mr values of 0.012 emu/g and0.011 emu/g, Hc values of 528.623 Oe and 473.327 Oe, respectively.