New composites of ZnO-P2O5/Ni having PTC transition and high Seebeck coefficient

► New composites of ZnO-P2O5/metal were studied electrically. ► Insulating-conducting phase transition was obtained with change of filler fraction. ► The observed transition is interpreted with percolation theory. ► High filling allowed PTC transition versus temperature, linking large electrical power. ► Rich Mott's mechanisms of transport were shown versus temperature at low filling.