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In this paper, we theoretically and experimentally reported a lead‐free pyroelectric infrared (PIR) detector using (Bi1/2Na1/2TiO3)‐BaTiO3(BNT‐BT) ferroelectric ceramics as the sensitive material. The variation of noise density, voltage response rate (RV), and specific detection rate (D*) with the modulation frequency under the current mode amplification circuit was investigated, and it was found that the lead‐free PIR detector showed high RV in the low frequency band. The RV and D* reached 1.51 × 105 V/W and 2.02 × 108 cmHz1/2W−1 at 10 Hz, respectively. The results were much superior to the PIR based on traditional commercial pyroelectric ceramics, indicating that BNT‐BT lead‐free ceramics have great potential in application to PIR detectors. [ABSTRACT FROM AUTHOR]

In this study, ternary ferroelectric 0.06Pb(Mn1/3Nb2/3)O3–0.94Pb(Zr0.48Ti0.52)O3 (PMN–PZT) thin film with high piezoelectric coefficient were grown on La0.6Sr0.4CoO3‐buffered Pt/Ti/SiO2/Si substrate by RF magnetron sputtering method. The phase and domain structure along with the macroscopic electrical properties were obtained. Under the optimized temperature of 550°C and sputtering pressure 0.9 Pa, the PMN–PZT film owned large remnant ferroelectric polarization of 62 μC/cm2. In addition, the PMN–PZT film had polydomain structures with fingerprint‐type nanosized domain patterns and typical local piezoelectric response. Through piezoelectric force microscopy, the PMN–PZT thin film at nanoscale exhibited obvious domain reversal when subjected to in situ poling field. It was further found that the quasi‐static piezoelectric coefficient of the PMN–PZT thin film reached 267 pC/N, which was about twice to that of the commercial PbZrO3–PbTiO3 (PZT) thin film. The optimized relaxor ferroelectric thin film PMN–PZT on silicon with global electrical properties shows great potential in the piezoelectric micro‐electro‐mechanical systems applications. [ABSTRACT FROM AUTHOR]

The piezoelectric and electromechanical properties of 0.94(Na1/2Bi1/2)TiO3–0.06BaTiO3 (NBT–6BT) lead-free piezoelectric ceramic by alternating current polarization (ACP) and direct current polarization (DCP) methods were studied in this work. Results indicated that the thickness-mode electromechanical coupling coefficients (kt) of the NBT–6BT which located around the morphotropic phase boundary (MPB) was significantly improved with an enhancement ratio of 28.6% from 58.1% to 74.7% after ACP compared to DCP. The ferroelectric domain structure and phase structure of the samples after ACP and DCP were investigated using piezoresponse force microscopy and X-ray diffraction, which revealed that the kt enhancement is mainly originated from the higher domain wall density boosted by the ACP. [ABSTRACT FROM AUTHOR]

BACKGROUND: Inorganic arsenic (iAs) is a well-known human carcinogen recognized by the World Health Organization and the International Agency for Research on Cancer. Currently, most iAs studies in populations are [...]