Sintering behaviour of CuO-doped SnO2

The sintering behaviour of CuO-doped SnO2 ceramics was studied. Additive-free SnO2 materials do not densify after heat treatment to 1400°C, whereas materials doped with 0.5–0.75 wt.% CuO densify to 98% of theoretical. Copper oxides (CuO/Cu2O) experience reduction and re-oxidation phenomena. There is no evidence of high vaporisation of SnO2, nor of liquid formation at low temperature (<1000°C) in the CuO–SnO2 system. This suggests that CuO acts by grain-boundary mechanisms.