Lead-Free Piezoelectric Ceramics

Enhanced Piezoelectric, Ferroelectric, and Electrostrictive Properties of Lead‐Free (1‐x)BCZT‐(x)BCST Electroceramics with Energy Harvesting Capability

“…Furthermore, the threat of removing the current exemptions, combined with the growing awareness of environmental and health issues related to these emissions, has further ignited this scientific interest in developing novel and effective Pb-free alternatives for utilization in a number of technologies. [11,12,14] In fact, in recent years, the scientific and engineering community directed significant efforts to develop alternate material systems to circumvent the use of Pb and to minimize the use of Pb-based piezoelectric materials in various technologies so that the environment can be protected along with the human health. [10][11][12]14] The design and development activities of Pb-free materials resulted in few alternate materials in recent years.…”

“…[11,12,14] In fact, in recent years, the scientific and engineering community directed significant efforts to develop alternate material systems to circumvent the use of Pb and to minimize the use of Pb-based piezoelectric materials in various technologies so that the environment can be protected along with the human health. [10][11][12]14] The design and development activities of Pb-free materials resulted in few alternate materials in recent years. Some of the alternate and Pb-free materials include BaTiO 3 (BT), (K 0.5 Na 0.5 )NbO 3 (KNN), (Bi 0.5 ,Ni 0.5 )TiO 3 (BNT), and (Bi 0.5 ,K 0.5 )TiO 3 (BKT), which are among the best prospects to replace Pb-based materials.…”

“…However, while developing the Pb-free materials, the progress of evolution continues to search for materials, which can exhibit properties comparable or even superior to PZT, as many of the contenders exhibit inferior piezoelectricity (d 33 < 150 pC N −1 in most cases), lower curie temperature, and high dielectric loss as compared to PZT. [14,16] Saito et al produced lead-free, KNN-based piezoelectric ceramics in 2004 that have a high piezoelectric coefficient of 416 pC N −1 and are compatible with the PZT. [16] Although the alkali-based materials, such as KNN, BNT, and BKT, showed promising electric properties, they have a limited range for sintering and are difficult to maintain stoichiometry in the finished product due to the presence of volatile and highly corrosive elements such as potassium and sodium, which also degrades the electromechanical properties.…”

“…[16] Although the alkali-based materials, such as KNN, BNT, and BKT, showed promising electric properties, they have a limited range for sintering and are difficult to maintain stoichiometry in the finished product due to the presence of volatile and highly corrosive elements such as potassium and sodium, which also degrades the electromechanical properties. [3][4][5]14] Furthermore, alkaline reagents are sensitive to humidity. For instance, KNN is notorious for having a small sintering range close to the solidus temperature (1140 °C), difficult microstructure control, easy emergence of secondary phases, and chemical heterogeneity, particularly when chemical modification is involved.…”

Special Issue: Emerging Dielectric, Piezoelectric, and Ferroelectric Ceramic and Crystalline Materials and Their Applications

“…Nowadays, piezoelectrics are based mainly on polycrystalline ferroelectric ceramics such as barium titanate (BaTiO 3 ) [ 2 ] and lead zirconate-titanate (PZT) [ 3 , 4 ], which exhibit larger displacements or induce larger electric voltages. Due to the adverse effects of lead on the environment, new effective lead-free piezoelectrics are still being sought out [ 5 ].…”