Fig. 5: Schematic illustration for stress, local electric field, and doping effects.

a Schematic illustration of AlN doped BCTZ–xAlN ceramics. Schematic illustration of the influence of (b) stress, (c) local electric field, and (d) doping effects on the performance of ceramics as functions of AlN doping concentration and particle size. The z-axis indicates performance parameters such as d33 or TC, where red represents higher values and purple indicates lower values.