Evolution of structural and electrical properties of (K,Na,Li)(Nb,Ta,Sb)O3 lead-free piezoceramics through CoO doping

Doping with transition metals is widely used for piezoceramic improvement. In this work, we study the effects of cobalt doping on the properties of the well known (K,Na,Li)(Nb,Ta,Sb)O3 piezoelectric ceramics. Two different situations were observed: for low concentrations, Co2+ cations occupy the A-site of the perovskite structure, whereas for high concentrations they occupy the B-site. The piezoelectric properties of the material are slightly affected with the cobalt concentration, whereas the mechanical quality factor increases by a factor of nearly three.