Percolative conduction in CdSe nanoparticles embedded in a silicon dioxide dielectric matrix

Studies on the dc electrical conductivity of SiO 2 /CdSe/SiO 2 nanocomposites in the temperature range of 150-370 K are presented. The existence of a threshold volume fraction of the semiconducting phase for the percolation conduction in the composites was observed. The results are in agreement with the predictions of the theoretical models proposed for granular metals. The temperature dependence of the dc conductivity in the higher temperature range (with T -1/2 variation) is in good agreement with the model of Sheng and Klafter.