Achieving superior energy harvesting performance in Sr-doped (Pb,La,Sb)(Zr,Ti)O3 ceramics based on optimization of FOM

The piezoelectric circular diaphragms (PCDs) applied to energy harvesters have great application potential for replacing chemical batteries to power microelectronic devices. However, the output power of PCDs is highly restricted by the value of d(33)(2)/epsilon(r) (defined as FOM) of selected materials. Herein, the (Pb0.925-xLa0.04Sb0.035Srx)(Zr0.55Ti0.45)(0.99)O-3 (abbreviated as PLSSZT, x = 0-0.06) ceramics prepared by the traditional solid-state method are reported. The results show that when x = 0.02, a morphotropic phase boundary (MPB) with a coexistence of rhombohedral (R) and tetragonal (T) phases is found which greatly optimizes the comprehensive properties of the ceramics (i.e., d(33) similar to 850 pC/N, k(p) similar to 62%, strain similar to 0.27% at 40 kV/cm). Meanwhile, the ceramics show a relatively low epsilon(r) of 3700 under 10 kHz, thus a large FOM can be achieved. Therefore, the PCD based on the (Pb0.905La0.04Sb0.035Sr0.02)(Zr0.55Ti0.45)(0.99)O-3 ceramics possesses a high output power of 8.3 mW under the 15 g proof mass, and can drive multiple LEDs, which is of reference significance for promoting the development of energy harvesters.