Electromagnetic transport properties and magnetoresistance of La{sub 0.7}Ca{sub 0.2}Sr{sub 0.1}MnO{sub 3}-Ag composites prepared by electroless process

A series of bulk polycrystalline La{sub 0.7}Ca{sub 0.2}Sr{sub 0.1}MnO{sub 3} (LCSMO)-Ag composites were prepared by electroless plating process and several kinds of physical properties have been studied systemically. According to the results of X-ray diffraction (XRD), scanning electron microscopy (SEM), and electromagnetic transport properties, we can see that Ag-added segregated at the surfaces or interfaces of LCSMO grains. The metal-insulator transition temperature (T{sub P}) and Curie temperature (T{sub c}) were almost unchanged but {rho} decreased with increasing plating time. We also observed Ag-added can significantly enhance the magnetoresistance (MR) near T{sub P} under a low applied field (3000 Oe) and the room temperature MR reached to 35% under 20 kOe, which is encouraging for practical applications. We can suggest that improved grain boundary effect by Ag-added is responsible for the enhancement. - Graphical abstract: Magnetic field dependence of the MR for the composites at 298 K. The inset is the different silver-plating time dependence of the variation of MR at 2 T.