Excellent Energy Storage Properties Achieved in Sodium Niobate-Based Relaxor Ceramics through Doping Tantalum

Abstract

Lead-free relaxor ferroelectric ceramics are potential for energy storage applications due to their comprehensive energy storage properties. However, the energy efficiency of many relaxor ceramics is not high enough, leading to high Joule heat during the charge−discharge cycles, thus lowering their energy storage performance. In this work, tantalum (Ta) dopants were introduced into sodium niobate-based relaxor ceramics to improve the resistivity and energy efficiency. The leakage current was reduced by Ta doping, especially at the high electric field. The enhanced resistivity is attributed to the increased bandgap induced by Ta doping. The impedance spectroscopy shows that both the grain and grain boundary resistivities are improved in the high temperature region. As a result, the optimal recoverable energy density and energy efficiency are 6.5 J/cm 3 and 94% at 450 kV/cm, respectively. In addition, the energy storage properties exhibit satisfactory temperature stability and cycling reliability. All these merits demonstrate that the Ta modified sodium niobatebased relaxor ceramic a potential candidate for high-power energy storage applications.

Lead-Free NaNbO3-Based Ceramics for Electrostatic Energy Storage Capacitors

“…)(Nb . Ta Ti (where x = 0.15) [108]. Such improvements have also been observed in various n ceramics, underscoring the broader applicability of this approach [109,110].…”

Superb Energy Storage Capability for NaNbO3‐Based Ceramics Featuring Labyrinthine Submicro‐Domains with Clustered Lattice Distortions

“…[8,9] Excellent ES properties derive from high breakdown strength E b , large maximum polarization P max and low remnant polarization P r . E b is closely related to material gene and microscopic characteristics (such as grain size [10] and defects, [11] etc), which can be enhanced by introducing a dielectric with a wide bandgap E g [12,13] and optimizing the sintering process. [14] These strategies are bound to affect material phase [15] and domain [16] structure, thus determining its P max and P r .…”

Configuration-entropy effects on BiFeO3–BaTiO3 relaxor ferroelectric ceramics for high-density energy storage

“…2 An enhanced bandgap was attributed to a high W rec = 6.5 J cm −3 and a high η = 94% accompanied by temperature stability in a Ta-doped sodium niobate-based relaxor ceramic, (Na 0.8 Bi 0.1 )(Nb 0.9− x Ta x Ti 0.1 )O 3 , with a high E b = 450 kV cm −1 . 32 NT-doped (Bi 0.5 Na 0.5 )TiO 3 exhibited a large P max with low P r owing to the coexistence of R 3 c nanodomains and P 4 bm PNRs. 33 These results demonstrated that NT promotes RFE behavior, causing lower P r and higher η .…”