High energy storage performance in AgNbO3 relaxor ferroelectric films induced by nanopillar structure

Inspired by the increasing demand for energy-storage capacitors in electrical and electronic systems, dielectrics with high energy-storage performance have attracted more and more attention. AgNbO3-based lead-free ceramics serve as one of the most promising environmental-friendly candidates. However, their energy storage optimization is seriously limited by the low breakdown strength. Fortunately, thin film as a form of AgNbO3 materials can effectively improve the breakdown strength. In this work, AgNbO3 film with ∼550 nm in thickness was deposited on SrRuO3/(001)SrTiO3 using pulsed laser deposition. The AgNbO3 film reveals typical relaxor ferroelectric hysteresis loops due to the new nanopillar structure, which contributes to high breakdown strength of up to 1200 kV cm–1. Benefiting from the high breakdown strength, a recoverable energy storage density of 10.3 J cm–3 and an energy efficiency of 72.2% are obtained in the AgNbO3 film, which demonstrates the promising prospect of AgNbO3 film for energy storage applications.