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(1 − x)K0.48Na0.52Nb0.95Sb0.05O3–xBi0.5Na0.5Zr0.95Ce0.05O3 [(1 − x)KNNS–xBNZC] lead-free piezoelectric ceramics, with doping ratio of x ranging from 0 to 0.05, were synthesized by the conventional solid state sintering method. The phase transition behavior, microstructure and piezoelectric properties of (1 − x)KNNS–xBNZC ceramics were systematically investigated using XRD, SEM, and other devices with different doping amounts of BNZC. It was found that the piezoelectric properties of (1 − x)KNNS–xBNZC ceramics were improved obviously by adding the proper doping amount, 0.03 < x < 0.04, due to the coexistence of rhombohedral and tetragonal phases in the ceramics near room temperature. The piezoelectric constant d33 of the ceramics first increased and then decreased when increasing the doping amount. A remarkably strong piezoelectricity was obtained in ceramics with a ∼441 pC N−1 peak d33 value. The excellent piezoelectric properties of (1 − x)KNNS–xBNZC ceramics with x = 0.034 were obtained: d33 = 441 pC N−1, kp = 0.44, Qm = 31, er = 2447, tan δ = 0.037, TC = 215 °C, Pr = 15.7 μC cm−2 and EC = 8.2 kV cm−1. With the annealing temperature reaching 250 °C, the d33 values of the ceramics were still greater than 330 pC N−1, which represents good temperature stability for the piezoelectric property. It is believed that such a material system is a very promising candidate for lead-free piezoelectric ceramics.

(LiCe)-modified (NaBi)0.48[ ]0.04Bi2Nb1.97W0.03O9 ceramics were prepared by conventional solid state sintering method, and the effect of doping on the electrical properties was studied. The dense microstructure with a high relative density ρrd (>98.12%) was well developed in this material system, presenting a typical Aurivillius phase structure. The Curie temperature (TC) gradually increases from 766 °C to 776 °C with increasing (LiCe) content, and moreover the addition of (LiCe) significantly increases the piezoelectric constant (d33). The (NaBi)0.43(LiCe)0.05[ ]0.04Bi2Nb1.97W0.03O9 ceramics exhibit optimum electrical properties (e.g., d33 ∼ 26.1 pC/N, kp ∼ 10.5%, and Qm ∼ 3209), together with a relatively high TC (∼771 °C) and good thermal stability until 750 °C. These results indicate that this ceramic is a promising candidate for high-temperature piezoelectric applications.

The effect of Ce-substitution for A -site on the electrical properties of (NaBi) 0.49 [ ] 0.02 Bi 2 Nb 1.98 Ta 0.02 O 9 -based piezoceramics prepared by the conventional solid state sintering method was investigated. The dense microstructure with ~98% theoretical density was well developed in this material system, presenting a typical Aurivillius phase structure. The Curie temperature ( T C ) gradually decreases from 791 °C to 770 °C with increasing Ce 3+ content. Moreover, doping with Ce 3+ significantly increases the piezoelectric constant ( d 33 ) and decreases the coercive field. The (NaBi 0.92 Ce 0.08 ) 0.49 [ ] 0.02 Bi 2 Nb 1.98 Ta 0.02 O 9 ceramic exhibits optimum electrical properties (e.g., d 33 ~24 pC/N, k p ~8.4%, Q m ~3488), together with a relatively high T C (~776 °C). These results indicate that this ceramic is a promising candidate for high-temperature piezoelectric applications.

The growth peculiarity of Sc thin film is simulated by a three-dimensional kinetic Monte Carlo method. The simulation results show that the surface root-mean-square roughness of Sc thin films is increased with the increasing of the deposition rate. The number of initial nucleus of Sc thin films is decreased gradually with the increasing of deposition temperature, and the size of the Sc grains gets larger with the increasing of the deposition temperature. The optimal deposition rate and deposition temperature of Sc thin film are predicted to be 10 ML/s or 3.308 nm/s, and 700 K, respectively.