Electrically conductive ceramic composites prepared with printer toner as the conductive phase

Conductive ceramic composite was prepared by sintering the mixture of clay and printer toner at 1050°C and in the N2 atmosphere. The microstructure and mineral phases of the ceramic composite were characterised by SEM, EDX, TG and XRD, and its electrical conductivity and mechanical properties were also investigated. The results show that, in the sintering process, a series of physical and chemical reactions take place, and mineral phases with excellent electrical conductivity, such as metal iron, carbon and Fe–Al solid solution material, are formed. The electrical conductivity mechanism can be explained by the percolation theory. The threshold value for electrical conductive percolation is between 3.5 and 7.0 wt-%. At the content of printer toner 10 wt-%, the volume electrical resistance of the ceramic composite is as low as 8.5 Ω cm, and the composite exhibits excellent flexural strength higher than 14 MPa.