Experimental Evidence of a Giant Capacitance in Insulator-Conductor Composites at the Percolation Threshold

Giant enhancement of the dielectric properties has been measured at the percolation threshold of a metal–insulator functional, graded composite using an in–situ electrical probe. The system reported (Mullite–Mo) combines very good thermal stability, low leakage currents, and very high capacitance, using dielectric materials with a low dielectric constant. Thus, devices made using this type of ceramic–metal supercapacitor may cover an important technological gap in high charge-storage devices, which could lead to a new generation of ceramic supercapacitors.