High performance lead‐free piezoelectric ceramics are of great importance to the sustainable development of the environment. To obtain excellent comprehensive performance KNN‐based lead‐free piezoelectric ceramics, a lattice distortion strategy combined with domain configuration was designed in (1 − x)K0.5Na0.5Nb0.95Sb0.05O3–xCaHfO3 ((1 − x)KNNS–xCH) system by introduced Ca2+ into the A‐site and Hf4+ into the B‐site. The results demonstrated that the rhombohedral–orthorhombic–tetragonal polymorphic phase boundary (PPB) was constructed in 0.02 ≤ x ≤ 0.04 and significant lattice distortion occurred in R‐ and T‐phase. Moreover, the 0.97KNNS–0.03CH sample exhibited excellent electrical performance (e.g., kp ∼ 43.8%, d*33 ∼ 478.6 pm/V, and d33 ∼ 392 pC/N) together with a high Curie temperature (TC ∼ 295°C) profited from the PPB and domain configurations. The ceramics also showed the optimal thermal stability, which was beneficial to promote the development of KNN‐based ceramics.

The piezoelectric energy harvesters (PEHs) are an important solution for wireless sensors to achieve self-powering, which require the piezoceramics not only have a large figure of merit (FOM = d2/)...

No abstract

A temperature-insensitive FOM was obtained in lead-free system with diffuse multiphase coexistence, and a record power density of 865 μW cm−3 at 80 °C was measured for cantilever beam-type PEH.

No abstract