Semiconducting densified SnO2-ceramics obtained by a novel sintering technique

Dense and electroconductive SnO2 ceramics, important for special electrodes applications, with the Sn0.75Cu0.083Sb0.167O2 final composition were densified by applying the Field Activated Sintering Technique (FAST). The same composition, obtained starting both from the initial oxides (i. e. SnO2, Sb2O3 and CuO) and from SnO2 and the CuSb2O6, was conventionally sintered by thermal treatment at 1100 °C–3 h. High relative density values (i.e. 99%) and a consolidated microstructure (grain size below 1 μm) were obtained only by applying FAST. The resulting SnO2-based solid solutions, presented a semimetallic behaviour sustained by the conductivity vs. temperature dependence and the obtained negative values for the Seebeck coefficients, with electrons as major charge carriers. For the conventional sintered specimens, the poor sintering capabilities evidenced by density and porosity measurements limited the electrical applications of the obtained materials as densified ceramics.