Highly (100)‐Oriented Bi(Ni _1/2 Hf _1/2 )O ₃ ‐PbTiO ₃ Relaxor‐Ferroelectric Films for Integrated Piezoelectric Energy Harvesting and Storage System

Abstract

Highly (100)‐oriented 0.38Bi(Ni 1/2 Hf 1/2 )O 3 ‐0.62PbTiO 3 relaxor‐ferroelectric films were fabricated on Pt(111)/Ti/SiO 2 /Si(111) substrates by introducing a lead oxide seeding layer. A moderate relative permittivity , a low dissipation factor (tan δ < 5%), and strong relaxor‐like behavior (γ = 0.74) over a broad temperature region were observed. The energy storage density of approximately 45.1 ± 2.3 J/cm 3 was achieved for films with (100) preferential orientation, which is much higher than the value ~33.5 ± 1.7 J/cm 3 obtained from films with random orientation. Furthermore, the PbO‐seeded films are more capable of providing larger piezoelectric response (~113 ± 10 pm/V) compared to the films without seeds (~85 ± 8 pm/V). These excellent features indicate that the highly (100)‐oriented 0.38Bi(Ni 1/2 Hf 1/2 )O 3 ‐0.62PbTiO 3 films could be promising candidates for applications in high‐energy storage capacitors, high‐performance MEMS devices, and particularly for potential applications in the next‐generation integrated multifunctional piezoelectric energy harvesting and storage system.