Introduction Ceramic-based dielectric capacitors with a high power density are one of the most prospective energy-storage components, compared with Li-ion batteries and super-capacitors. Unfortunately, the energy-storage density of ceramic-based dielectric capacitors is one or two orders of magnitude lower than that of the batteries, which is restricted by the property of dielectric materials. Therefore, developing reliable and high-performance dielectric ceramic is a challenge in the field of dielectric capacitors. Among dielectric ceramics, antiferroelectic (AFE) material is one of the most promising candidates for energy-storage devices since they show a high maximum polarization (Pmax), low remnant polarization (Pr), and a regulated AFE-ferroelectric (FE) phase transition electric field. Recent efforts are made to enhance energy-storage properties of ceramic by component design, ion-doping and material form construct. However, a superior η is always gained at the cost of a high Wrec, becoming a challenge for synergistically achieving a ultrahigh Wrec and a superior η.Methods High-purity Pb3O4 (≥95.0%, Sinopharm Chemical Reagent Co., Ltd., China), La2O3 (≥99.9%, Sinopharm Chemical Reagent Co., Ltd., China), Nd2O3 (>99.99%, Aladdin Biochemical Technology Co., Ltd., China), ZrO2 (≥99.0%, Sinopharm Chemical Reagent Co., Ltd., China), and SnO2 (≥99.5%, Sinopharm Chemical Reagent Co., Ltd.) were used as raw materials. Pb0.98-1.5xLa0.02Ndx(Zr0.60Sn0.40)0.995O3 (PL100xNZS) was selected as a basic system. Nd3+ with a small ionic radius (i.e., 1.29 ?) was introduced in PLZS to replace Pb2+ (i.e., 1.49 ?) for enhancing electric filed-induced EFE-AFE. A Pb0.98-1.5xLa0.02Ndx(Zr0.60Sn0.40)0.995O3 component was designed and the ceramics were fabricated by a tape-casting method.The crystallinity, phase structure and microstructure of PL100xNZS ceramics were analyzed by an X-ray diffractometer (Rigaku Co., Ltd., Japan) and a model TESCAN-MIRA3 field-emission scanning electron microscope (TESCAN Co., Czech). The dielectric properties of the PL100xNZS ceramics were measured by a computer-controlled Agilent E4980A LCR analyzer. The displace-electric field (D-E) hysteresis loops and current density-electric field curve were determined by a ferroelectric measurement system (Radiant Technologies Co., USA). The pulsed charge-discharge behaviors were determined by a model CFD-001 resistance-inductance- capacitance (R-L-C) electric circuit (Guoguo Technology Co., China). Results and discussion The XRD patterns show that all the samples exhibit a perovskite structure with an orthorhombic phase. The SEM images show that a dense and compact microstructure appears in PL100xNZS ceramics. The average grain size is decreased by doping of Nd3+. The dielectric behavior of PL100xNZS ceramics as a function of temperature measured at 10 kHz and 25-400 ℃ indicates that there are three stages of dielectric constant with the increase of temperature, i.e., the rising, the plateau and the falling regions, which correspond to the AFE, multicell cubic (MCC) and single-cell cubic (PEC) phases. The maximum polarization decreases at the same electric field, and the breakdown strength (BDS) increases with the increase of Nd3+ content due to the decreased grain size. The antiferroelectric-ferroelectric phase transition electric field (EAFE-FE) increases as the Nd3+ content increases, because of a stable antiferroelectric phase. The enhanced BDS and increased EAFE-FE imply a high energy-storage density. The recoverable energy-storage density and efficiency are critical parameters to characterize the material performance. Herein, the PL4NZS ceramic can be used as a promising energy-storage material because it exhibits a linear-like D-E loop with a large Pmax (i.e., 60 μC/cm2) and a high BDS (i.e., 490 kV/cm). A large energy storage density of 14.8 J/cm3 is obtained in PL4NZS ceramic with a high efficiency of 85%. The calculated values of Wrec and η fluctuate slightly in the range of 6.18-4.88 J/cm3 with increasing the frequency. The discharge waveforms of PL4NZS ceramic at different electric fields are investigated at room temperature with an overdamped R-L-C electric circuit. The maximum value of Wdis is 4.4 J/cm3 at 300 kV/cm, and the t0.9 is 28 ns. A large CDmax of 3 360 A/cm2 and a high PDmax of 504 MW/cm3 are achieved at 300 kV/cm in PL4NZS ceramic, indicating that the PL4NZS ceramic has a great competitiveness in high power system applications. Conclusions The high energy-storage density and efficiency were realized in designed PL100xNZS ceramics fabricated by a tape-casting technique. The effects of Nd3+ doping on the microstructure, dielectric properties, ferroelectric properties and energy storage properties of the ceramics were investigated. The Wrec was 14.8 J/cm3 with a giant η of 85% at 490 kV/cm for PL4NZS ceramic. As the temperature increases, Wrec and η of PL4NZS ceramic increased slightly. Moreover, a high Wdis of 4.4 J/cm3, a large CDmax of 3 360 A/cm2 and a high PDmax of 504 MW/cm3 were obtained in PL4NZS ceramic. It was indicated that PL4NZS ceramic could be used as a prospective dielectric material for energy-storage applications.