Mingxing Zhou

Bio: Mingxing Zhou is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Energy storage & Dielectric. The author has an hindex of 17, co-authored 24 publications receiving 1400 citations.

Novel BaTiO3-based lead-free ceramic capacitors featuring high energy storage density, high power density, and excellent stability

Abstract: The development of energy storage devices with a high energy storage density, high power density, and excellent stability has always been a long-cherished goal for many researchers as they tackle issues concerning energy conservation and environmental protection. In this work, we report a novel BaTiO3-based lead-free composition (0.85BaTiO3–0.15Bi(Zn1/2Sn1/2)O3) with an ultrahigh energy storage density (2.41 J cm−3) and a high energy storage efficiency of 91.6%, which is superior to other lead-free systems reported recently. The energy storage properties of 0.85BT–0.15BZS ceramic manifest excellent frequency stability (5–1000 Hz) and fatigue endurance (cycle number: 105). The pulsed charging–discharging process is measured to elucidate the actual operation performance in the 0.85BT–0.15BZS ceramic. Delightfully, the 0.85BT–0.15BZS ceramic also possesses an ultrahigh current density of 551 A cm−2 and a giant power density of 30.3 MW cm−3, and the stored energy is released in sub-microseconds. Moreover, the 0.85BT–0.15BZS ceramic exhibits outstanding temperature stability of its dielectric properties, energy storage properties, and charging–discharging performance over a broad temperature range (20–160 °C) due to the weakly-coupled relaxor behavior. These results not only indicate the superior potential of environment-friendly BaTiO3-based relaxor ferroelectric ceramics for the design of ceramic capacitors of both high energy storage and power applications, but they also show the merit of the weakly-coupled relaxor behavior to improve the thermal stability of energy storage properties.

Superior energy storage properties and excellent stability of novel NaNbO3-based lead-free ceramics with A-site vacancy obtained via a Bi2O3 substitution strategy

Abstract: This study presents an innovative strategy to improve the energy storage properties of NaNbO3 lead-free ceramics by the addition of Bi2O3. The introduction of Bi2O3 can effectively increase the breakdown strength and decrease the remnant polarization of NaNbO3 ceramics. Meanwhile, hybridization between the O2− 2p and Bi3+ 6p orbitals can enhance the polarization. The novel NaNbO3-based (Na0.7Bi0.1NbO3) ceramics demonstrate ultrahigh energy storage efficiency of 85.4% and remarkably high energy storage density (4.03 J cm−3) at 250 kV cm−1 simultaneously, which are superior to the results of almost all recently reported lead-free alternatives. The outstanding stability of energy storage characteristics in terms of frequency (1–1000 Hz), temperature (20–120 °C) and fatigue (cycle number: 105) is also observed in Na0.7Bi0.1NbO3 ceramics. Furthermore, additional pulsed charge–discharge measurements for Na0.7Bi0.1NbO3 ceramics are also carried out to evaluate actual operation performance. The Na0.7Bi0.1NbO3 ceramics exhibit extremely high power density (62.5 MW cm−3) and current density (1250 A cm−2) and release all stored energy rapidly (∼155 ns) under various electric fields and temperatures. These properties qualify these environment-friendly Na0.7Bi0.1NbO3 ceramics as innovative and most promising alternatives for energy storage applications, especially for high power and pulsed power system applications.

Novel Sodium Niobate-Based Lead-Free Ceramics as New Environment-Friendly Energy Storage Materials with High Energy Density, High Power Density, and Excellent Stability

Abstract: Recently, ceramic capacitors with fast charge–discharge performance and excellent energy storage characteristics have received considerable attention. Novel NaNbO3-based lead-free ceramics (0.80NaN...

Enhanced energy storage properties in sodium bismuth titanate-based ceramics for dielectric capacitor applications

Abstract: There are imperious demands for developing eco-benign energy storage materials with high-performance in a sustainable society. In this paper, we introduce Sr0.85Bi0.1□0.05TiO3 (SBT) and NaNbO3 (NN) into Bi0.5Na0.5TiO3 (BNT) ceramics through compositional design. The introduction of Sr2+ ions and vacancies at the A-sites constructs relaxor ferroelectrics according to order–disorder theory. The introduction of Nb5+ ions at the B-sites is confirmed to have two major implications. In one way, it boosts a higher induced polarization due to its intrinsic larger polarizability and overall stronger degree of diffuseness. In another, it contributes to forming a core–shell microstructure, as proven using transmission electron microscopy, promoting the breakdown strength (BDS) to a higher level. With the above strategies, our BNT–SBT–4NN ceramics demonstrate excellent energy storage performances with simultaneously ultrahigh energy storage density (W ∼ 3.78 J cm−3), recoverable energy storage density (Wrec ∼ 3.08 J cm−3) and efficiency (81.4%). Furthermore, the ceramics possess excellent discharge energy density (Wd = 0.854 J cm−3) and rapid discharge speed (t0.9 ∼ 100 ns) in a wide temperature range, proving their high application potential. Our results break through the bottleneck of BNT-based ferroelectrics with a general recoverable energy storage density of lower than 3 J cm−3, making the BNT–SBT–4NN ceramic a powerful candidate material for use in energy storage applications.

Excellent comprehensive energy storage properties of novel lead-free NaNbO3-based ceramics for dielectric capacitor applications

Abstract: NaNbO3 (NN) is generally considered as one of the most promising lead-free antiferroelectric (AFE) perovskite materials with the advantages of low cost, low density and nontoxicity. However, the metastable ferroelectric phase causes a large remanent polarization (Pr) at room temperature, seriously hindering the achievement of excellent energy storage properties. Although via the strategy of lowering the radius of B-site ions and polarizability, a number of AFE NaNbO3-based solid solutions with double polarization–electric field loops are successfully constructed, the hysteresis losses are still too large and the Pr value cannot be reduced to near zero. In this study, Bi(Mg2/3Nb1/3)NbO3 (BMN) was chosen to partially substitute the pure NaNbO3 with the intention of enhancing antiferroelectricity and constructing a local random field simultaneously. These short-range interactions effectively suppress the hysteresis loss and Pr, and slim hysteresis loops were observed in the NN–BMN ceramics. A high charged energy density (3.4 J cm−3) and recoverable energy storage density (2.8 J cm−3) with high efficiency (82%) were achieved under 300 kV cm−1 for NN–0.10BMN. Superior stabilities and underdamped discharge abilities were also achieved for NN–0.15BMN with a slightly smaller recoverable energy storage density (2.4 J cm−3) but even higher efficiency (90%). The results reported here demonstrate great potential of the designed NN–BMN ceramics for high-temperature capacitors.

Electroceramics for High-Energy Density Capacitors: Current Status and Future Perspectives

Abstract: Materials exhibiting high energy/power density are currently needed to meet the growing demand of portable electronics, electric vehicles and large-scale energy storage devices. The highest energy densities are achieved for fuel cells, batteries, and supercapacitors, but conventional dielectric capacitors are receiving increased attention for pulsed power applications due to their high power density and their fast charge-discharge speed. The key to high energy density in dielectric capacitors is a large maximum but small remanent (zero in the case of linear dielectrics) polarization and a high electric breakdown strength. Polymer dielectric capacitors offer high power/energy density for applications at room temperature, but above 100 °C they are unreliable and suffer from dielectric breakdown. For high-temperature applications, therefore, dielectric ceramics are the only feasible alternative. Lead-based ceramics such as La-doped lead zirconate titanate exhibit good energy storage properties, but their toxicity raises concern over their use in consumer applications, where capacitors are exclusively lead free. Lead-free compositions with superior power density are thus required. In this paper, we introduce the fundamental principles of energy storage in dielectrics. We discuss key factors to improve energy storage properties such as the control of local structure, phase assemblage, dielectric layer thickness, microstructure, conductivity, and electrical homogeneity through the choice of base systems, dopants, and alloying additions, followed by a comprehensive review of the state-of-the-art. Finally, we comment on the future requirements for new materials in high power/energy density capacitor applications.

Novel BaTiO3-based lead-free ceramic capacitors featuring high energy storage density, high power density, and excellent stability

Abstract: The development of energy storage devices with a high energy storage density, high power density, and excellent stability has always been a long-cherished goal for many researchers as they tackle issues concerning energy conservation and environmental protection. In this work, we report a novel BaTiO3-based lead-free composition (0.85BaTiO3–0.15Bi(Zn1/2Sn1/2)O3) with an ultrahigh energy storage density (2.41 J cm−3) and a high energy storage efficiency of 91.6%, which is superior to other lead-free systems reported recently. The energy storage properties of 0.85BT–0.15BZS ceramic manifest excellent frequency stability (5–1000 Hz) and fatigue endurance (cycle number: 105). The pulsed charging–discharging process is measured to elucidate the actual operation performance in the 0.85BT–0.15BZS ceramic. Delightfully, the 0.85BT–0.15BZS ceramic also possesses an ultrahigh current density of 551 A cm−2 and a giant power density of 30.3 MW cm−3, and the stored energy is released in sub-microseconds. Moreover, the 0.85BT–0.15BZS ceramic exhibits outstanding temperature stability of its dielectric properties, energy storage properties, and charging–discharging performance over a broad temperature range (20–160 °C) due to the weakly-coupled relaxor behavior. These results not only indicate the superior potential of environment-friendly BaTiO3-based relaxor ferroelectric ceramics for the design of ceramic capacitors of both high energy storage and power applications, but they also show the merit of the weakly-coupled relaxor behavior to improve the thermal stability of energy storage properties.

Linear-like lead-free relaxor antiferroelectric (Bi0.5Na0.5)TiO3–NaNbO3 with giant energy-storage density/efficiency and super stability against temperature and frequency

Abstract: A novel lead-free polar dielectric ceramic with linear-like polarization responses was found in (1 − x)(Bi0.5Na0.5)TiO3–xNaNbO3 ((1 − x)BNT–xNN) solid solutions, exhibiting giant energy storage density/efficiency and super stability against temperature and frequency. High-resolution transmission electron microscopy, Raman scattering and Rietveld refinements of X-ray diffraction data suggest that these property characteristics can be derived from temperature and electric field insensitive large permittivity as a result of relaxor antiferroelectricity (AFE) with polar nanoregions. Additionally, this feature intrinsically requires a high driving field for AFE to ferroelectric (FE) phase transitions due to large random fields. Measurements of temperature-dependent permittivity and polarization versus electric field hysteresis loops indicate that the high-temperature AFE P4bm phase in BNT was gradually stabilized close to room temperature, accompanying a phase transition from relaxor rhombohedral FEs to relaxor tetragonal AFEs approximately at x = 0.15–0.2. A record high of recoverable energy-storage density W ∼ 7.02 J cm−3 as well as a high efficiency η ∼ 85% was simultaneously achieved in the x = 0.22 bulk ceramic, which challenges the existing fact that W and η must be seriously compromised. Furthermore, desirable W (>3.5 J cm−3) and η (>88%) with a variation of less than 10% can be accordingly obtained in the temperature range of 25–250 °C and frequency range of 0.1–100 Hz. These excellent energy-storage properties would make BNT-based lead-free AFE ceramic systems a potential candidate for application in pulsed power systems.