Temperature‐independent large strain with small hysteresis in Sb‐modified BNT‐based lead‐free ceramics

Abstract

Chemically modified (typically, via B-site doping by Nb and Ta) Bi 0.5 Na 0.5 TiO 3 (BNT)-based piezoelectric ceramics, which exhibit superior electro-strain behaviors than their perovskite peers, suffer from high hysteresis and poor temperature stability. In this study, the rarely studied dopant Sb is found to be effective in overcoming these two drawbacks by expanding the ergodic relaxor region to a wider temperature range. Excellent electro-strain (0.41%-0.46%) with reduced hysteresis (15%-20%) was observed over the temperature range of 40-120°C, with 12% variation of electro-strain in Bi 0.5 (Na 0.78 K 0.22 ) 0.5 Ti 0.9925 Sb 0.0075 O 3 samples. These results suggest that compared to previously reported BNT-based piezoelectric ceramics, Sb-modified BNT-based ceramics show higher potential for practical actuator applications.

Ultrahigh electrostrain with excellent fatigue resistance in textured Nb 5+-doped (Bi 0.5Na 0.5)TiO 3-based piezoceramics

“…For example, Zhang et al [18] prepared BNT-BT-0.02KNN lead-free piezoceramics for the first time, and a large electrostrain of 0.45% at an electric field of 8 kV/mm with the corresponding large signal piezoelectric coefficient * 33 ( ) d of 560 pm/V was achieved, which was comparable to that of the lead-based piezoelectric ceramics. A large electrostrain of 0.46% at an electric field of 8 kV/mm with good temperature stability was achieved for Bi 0.5 (Na 0.78 K 0.22 ) 0.5 Ti 0.9925 Sb 0.0075 O 3 piezoceramics by Wang et al [19]. Enhanced electrostrains of 0.70% and 0.62% at 5 kV/mm for [(Bi 1/2 (Na 0.84 K 0.16 ) 1/2 ) 0.96 Sr 0.04 ](Ti 0.975 Nb 0.025 )O 3 and [Bi 1/2 (Na 0.8 K 0.2 ) 1/2 ](Ti 0.985 Ta 0.015 )O 3 lead-free piezoceramics were obtained, respectively; however, high hysteresis (~68.9%) and poor fatigue resistance property (decreasing 14% after only 100 cycles) were accompanied [20,21].…”

0.90(0.88NaNbO3-0.12Bi(Ni0.5Zr0.5)O3)-0.10CaTiO3 Lead-Free Dielectric Ceramics with High Energy Storage Properties

“…For example, BST-BMZ and BST-BZN ceramics studied by Wang , and NN-BMN-BNST ceramics studied by Dong have made excellent scientific progress . Although lead-free perovskite energy storage ceramics can be environmentally friendly, there are still problems such as low energy storage efficiency. , Among them, BNT and BaTiO 3 -based ceramics have the disadvantage of poor temperature stability, and BiFeO 3 -based ceramics have insufficient industrial practicability . Compared with other systems, NaNbO 3 material has the characteristics of antiferroelectric, high polarization strength, relative breakdown resistance, light weight, and wide operating temperature range, which widely attracts attention from many researchers.…”

“…12 Although lead-free perovskite energy storage ceramics can be environmentally friendly, there are still problems such as low energy storage efficiency. 8,13 Among them, BNT and BaTiO 3 -based ceramics have the disadvantage of poor temperature stability, 14 and BiFeO 3 -based ceramics have insufficient industrial practicability. 15 wide operating temperature range, which widely attracts attention from many researchers.…”

BNT‐based relaxor/ferroelectric systems: Improved field‐induced strain property in the layered composite ceramics

“…Piezoelectric actuators can convert the input electrical energy into mechanical strain and are considered to be one of the most useful microactuators owing to their advantages of high precision displacement, large driving force, and easy miniaturization. [1][2][3][4] Undoubtedly, the fieldinduced strain behavior of the piezoelectric materials is a key factor in deciding the property of actuator devices.…”