Ultrafast discharge properties and enhanced energy density in lead‐free NaNbO3‐based relaxor ferroelectric ceramics

Abstract NaNbO 3 ‐based (NN) energy storage ceramics are known for exhibiting high maximum polarization ( P max ) and large recoverable energy density ( W rec ). However, the huge energy loss density ( W loss ) has been a limiting factor in improving energy storage performance. Therefore, a ternary system was designed to achieve both huge W rec and efficiency ( η ). The combination of 0.35Bi(Zn 0.5 Ti 0.5 )O 3 –0.65BaTiO 3 (BZTBT) was chosen to reduce grain size and disrupt the long‐range ordered domains, thereby inducing the polar‐nano‐regions to mitigate W loss . The optimal performance was achieved with the 0.75NaNbO 3 –0.25(0.35Bi(Zn 0.5 Ti 0.5 )O 3 –0.65BaTiO 3 ) (0.75NN–0.25BZTBT) ceramic, which exhibited a high W rec = 2.68 J/cm 3 and superior η = 82.7% under 310 kV/cm. Remarkably, the 0.75NN–0.25BZTBT ceramic displayed an exceptionally fast discharge time to 90%, t 0.9 = 88 ns, coupled with a huge energy density W d = 0.95 J/cm 3 . This study demonstrates the significant potential of 0.75NN–0.25BZTBT ceramic in the realm of energy storage and rapid charge–discharge applications.