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 BaZr0.5Ti0.5O3-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. Entropy-modulated Ba(Zr, Ti)O3-based films with high orientation are prepared, and the continuous evolution of dielectric properties with entropy is studied. Significantly suppressed leakage current density leads to an ultrahigh breakdown strength of 8 MV cm-1 and enhances energy density of 51.9 J cm-3 in the high-entropy films, thereby providing a feasible approach to high-performance energy storage capacitors. image