Enhanced Energy Storage Properties in Paraelectrics via Entropy Engineering

Electrostatic energy storage capacitors based on dielectrics have attracted much attention due to their wide applications in advanced electrical technology and electronic devices. Generally, high energy density is achieved at a high electric field, while conduction loss becomes nonnegligible, which harms practical applications. Here distinctly suppressed leakage current in BaZr 0.5 Ti 0.5 O 3 -based films by entropy engineering is realized. With increased entropy, the leakage current density decreases by two orders of magnitude at the electric field of 3 MV cm −1 , leading to a markedly improved energy efficiency of 87% at an ultrahigh breakdown strength of 8 MV cm −1 in high-entropy films. Thereby, a high energy density of 51.9 J cm −3 is achieved. This work demonstrates the effectiveness of entropy engineering in improving the breakdown strength of dielectric films and shows great potential in enhancing the energy storage performance of capacitors.