As essential fundamental electronic components, high-energy-density dielectric capacitors play a critical role in modern industry and defense technology, thanks to their high discharge power, efficient energy utilization, rapid charge-discharge response, excellent cycling durability, and stable performance. However, capacitors currently available on the market still generally suffer from limitations such as relatively low energy storage density, limited output current capability, and short service life, which lead to larger overall device sizes and constrain their further application in compact systems. Developing dielectric composite films featuring simultaneously high stored-energy density and excellent discharge efficiency is crucial for advancing power electronic devices toward miniaturization, downsizing, and lightweight design. In this study, one-dimensional BaZr0.3Ti0.7O3 nanofibers (BZT NFs) were synthesized via the electrospinning technique and incorporated as functional fillers into a PVDF polymer matrix. To improve the dispersion uniformity of the nanofibers in the organic matrix, enhance the interfacial compatibility between the inorganic and organic phases, and further boost the overall performance of the composite system, surface hydroxylation treatment was applied to modify the fibers t (denoted as BZT NF-OH). Subsequently, one-dimensional BZT NF-OH/PVDF dielectric composite films were fabricated through a doctor-blade film-casting process. Combining experimental characterization with theoretical simulations, the influence of surface hydroxylation treatment on the dielectric properties, breakdown strength, and energy storage density of the composites was systematically analyzed.
The as-prepared BZT NFs exhibited well-defined one-dimensional morphology, with diameters ranging from 80 to 240 nm and lengths extending from 11.4 μm, showing excellent dispersibility. Surface hydroxylation significantly enhanced the uniform dispersion of nanofibers within the PVDF matrix and strengthened interfacial adhesion. Dielectric measurements revealed that the incorporation of BZT NF-OH effectively increased the dielectric constant of the composites; at a filler loading of 7.5vol%, the room-temperature dielectric constant reached 20.1, accompanied by reduced dielectric loss. As the filler concentration increased, the breakdown strength of the composite system decreased slightly. This was attributed to the introduction of local defects or micro-voids caused by the incorporation of BZT NF fillers into the PVDF matrix, which led to uneven electric field distribution and consequently a reduction in breakdown strength. Energy storage analysis demonstrated that the composite film with 2.5 vol. % BZT NF-OH achieved a high energy storage density of 8.31 J/cm3, representing a 189% enhancement compared to pristine PVDF. The composite exhibited the optimal efficiency performance. At electric fields below 1 000 kV/cm, the discharge efficiency remained above 84%, even under a high electric field of 3 850 kV/cm, the efficiency could still be maintained above 60%, both significantly superior to those of the pure PVDF. This remarkable improvement was attributed to a dual effect induced by hydroxylation, which improved dispersion homogeneity and optimized interfacial compatibility. Finite element simulations further confirmed that surface hydroxylation promoted a more uniform electric field distribution within the composite, suppressed localized electrical breakdown, and thereby enhanced overall dielectric strength.
In conclusion, surface hydroxylation serves as an effective strategy to tailor the interface between BZT nanofibers and the PVDF matrix, enabling simultaneous enhancement of dielectric constant and breakdown strength at low filler content. This work provides a promising pathway for the design and development of high-performance dielectric capacitors.
Key words
PVDF /
BaZr0.3Ti0.7O3 /
one-dimensional nanofibers /
composites /
surface hydroxylation /
energy storage performance /
dielectric properties
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References
[1] ZHAO S, PENG W F, ZHOU L, et al.Metal-Organic Cage Crosslinked Nanocomposites with Enhanced High- Temperature Capacitive Energy Storage Performance[J]. Nature Communications, 2025, 16: 769.
[2] ZHA J W, TIAN Y Y, ZHENG M S, et al.High- Temperature Energy Storage Polyimide Dielectric Materials: Polymer Multiple-Structure Design[J]. Materials Today Energy, 2023, 31: 101217.
[3] YANG M Z, REN W B, GUO M F, et al.High-Energy- Density and High Efficiency Polymer Dielectrics for High Temperature Electrostatic Energy Storage: A Review[J]. Small, 2022, 18(50): 2205247.
[4] REN W B, YANG M Z, ZHOU L, et al.Scalable Ultrathin All-Organic Polymer Dielectric Films for High- Temperature Capacitive Energy Storage[J]. Advanced Materials, 2022, 34(47): 2207421.
[5] JIANG Y, HUANG Y, FAN Z H, et al.Energy Density and Efficiency of Scalable Polymer Nanocomposites Utilizing Core-Shell PLZST@Al2O3 Antiferroelectric Fillers with Dielectric Gradient[J]. Chemical Engineering Journal, 2022, 446: 136925.
[6] 陈铃, 刘兴博, 郭旭, 等. 钛酸酯偶联剂表面改性Ba0.6Sr0.4TiO3纳米纤维对PVDF复合薄膜介电和储能性能影响[J]. 表面技术, 2026, 55(8): 217-228.
CHEN L, LIU X B, GUO X, et al.Effect of Surface Modification of Ba0.6Sr0.4TiO3 Nanofibers with the Titanate Coupling Agent on the Dielectric and Energy Storage Properties of PVDF Composite Films[J]. Surface Technology, 2026, 55(8): 217-228.
[7] YU X M, WANG J C, SUN Y, et al.Fabrication and Enhanced Dielectric Constant of Nanocomposite Films Based on Polyimide and Core-Shell Structured Al2O3@0.4mol%Nb-(Ba0.87Sr0.04Ca0.09)(Ti0.86Zr0.08Sn0.06)O3 Nanoparticles[J]. Journal of Materials Science: Materials in Electronics, 2019, 30(15): 14391-14404.
[8] FU J, YANG M C, WANG R, et al.Improvement of High-Temperature Energy Storage Performance in Polymer Dielectrics by Nanofillers with Defect Spinel Structure[J]. Materials Today Energy, 2022, 29: 101101.
[9] 刘少辉, 王娇, 王菲菲, 等. 氧化铝包覆SrTiO3纳米纤维/聚偏氟乙烯复合材料的制备与介电储能性能[J]. 表面技术, 2023, 52(8): 346-354.
LIU S H, WANG J, WANG F F, et al.Dielectric Energy Storage Performance of Alumina Coated SrTiO3 Nanofiber/Polyvinylidene Fluoride Composites[J]. Surface Technology, 2023, 52(8): 346-354.
[10] YANG L T, KONG X, LI F, et al.Perovskite Lead-Free Dielectrics for Energy Storage Applications[J]. Progress in Materials Science, 2019, 102: 72-108.
[11] TANG L P, NING W Z, WU S, et al.Energy Storage Performance of High-Entropy SBN-Based Tungsten Bronze-Structure Ceramic[J]. Journal of Alloys and Compounds, 2025, 1015: 178902.
[12] YU Y G, SHAO W Z, LIU Y, et al.Achieving High Energy Storage in BaTiO3/rGO/PVDF Nanocomposites by Regulating the Charge Transfer Path at the Hetero- Interface[J]. Journal of Materials Chemistry A, 2023, 11(10): 5279-5287.
[13] DUN C C, KUANG W Z, KEMPF N, et al.3D Printing of Solution-Processable 2D Nanoplates and 1D Nanorods for Flexible Thermoelectrics with Ultrahigh Power Factor at Low-Medium Temperatures[J]. Advanced Science, 2019, 6(23): 1901788.
[14] DANG Z M, YUAN J K, YAO S H, et al.Flexible Nanodielectric Materials with High Permittivity for Power Energy Storage[J]. Advanced Materials, 2013, 25(44): 6334-6365.
[15] FENG D D, YU K, WANG H.Dielectric Properties of CCTO/Poly(vinylidene fluoride) Composites for Energy Storage Applications[J]. Journal of Advanced Physics, 2015, 4(4): 384-387.
[16] SONG Y, SHEN Y, HU P H, et al.Significant Enhancement in Energy Density of Polymer Composites Induced by Dopamine-Modified Ba0.6Sr0.4TiO3 Nanofibers[J]. Applied Physics Letters, 2012, 101(15): 152904.
[17] FAN Y Y, WANG G Y, HUANG X Y, et al.Molecular Structures of (3-Aminopropyl)Trialkoxysilane on Hydroxylated Barium Titanate Nanoparticle Surfaces Induced by Different Solvents and Their Effect on Electrical Properties of Barium Titanate Based Polymer Nanocomposites[J]. Applied Surface Science, 2016, 364: 798-807.
[18] YANG K, HUANG X Y, HE J L, et al.Strawberry-Like Core-Shell Ag@Polydopamine@BaTiO3 Hybrid Nanoparticles for High-k Polymer Nanocomposites with High Energy Density and Low Dielectric Loss[J]. Advanced Materials Interfaces, 2015, 2(17): 1500361.
[19] LIU S H, XUE S X, XIU S M, et al.Surface-Modified Ba(Zr0.3Ti0.7)O3 Nanofibers by Polyvinylpyrrolidone Filler for Poly(vinylidene fluoride) Composites with Enhanced Dielectric Constant and Energy Storage Density[J]. Scientific Reports, 2016, 6: 26198.
[20] PAN Z B, YAO L M, ZHAI J W, et al.Excellent Energy Density of Polymer Nanocomposites Containing BaTiO3@Al2O3nanofibers Induced by Moderate Interfacial Area[J]. Journal of Materials Chemistry A, 2016, 4(34): 13259-13264.
[21] ZHOU T, ZHA J W, HOU Y, et al.Surface-Functionalized MWNTS with Emeraldine Base: Preparation and Improving Dielectric Properties of Polymer Nanocomposites[J]. ACS Applied Materials & Interfaces, 2011, 3(12): 4557-4560.
[22] ZHANG X, SHEN Y, SHEN Z H, et al.Achieving High Energy Density in PVDF-Based Polymer Blends: Suppression of Early Polarization Saturation and Enhancement of Breakdown Strength[J]. ACS Applied Materials & Interfaces, 2016, 8(40): 27236-27242.
[23] SHEN Y, SHEN D S, ZHANG X, et al.High Energy Density of Polymer Nanocomposites at a Low Electric Field Induced by Modulation of Their Topological- Structure[J]. Journal of Materials Chemistry A, 2016, 4(21): 8359-8365.
[24] WANG T, PENG R C, PENG W J, et al.2-2 Type PVDF-Based Composites Interlayered by Epitaxial (111)- Oriented BTO Films for High Energy Storage Density[J]. Advanced Functional Materials, 2022, 32(10): 2108496.
[25] WANG P J, GUO Y, ZHOU D, et al.High-Temperature Flexible Nanocomposites with Ultra-High Energy Storage Density by Nanostructured MgO Fillers[J]. Advanced Functional Materials, 2022, 32(31): 2204155.
[26] KIM P, DOSS N M, TILLOTSON J P, et al.High Energy Density Nanocomposites Based on Surface-Modified BaTiO3 and a Ferroelectric Polymer[J]. ACS Nano, 2009, 3(9): 2581-2592.
[27] YU K, NIU Y J, BAI Y Y, et al.Poly(vinylidene fluoride) Polymer Based Nanocomposites with Significantly Reduced Energy Loss by Filling with Core-Shell Structured BaTiO3/SiO2 Nanoparticles[J]. Applied Physics Letters, 2013, 102(10): 102903.
[28] YU K, NIU Y J, ZHOU Y C, et al.Nanocomposites of Surface-Modified BaTiO3 Nanoparticles Filled Ferroelectric Polymer with Enhanced Energy Density[J]. Journal of the American Ceramic Society, 2013, 96(8): 2519-2524.
[29] XIA W M, XU Z, WEN F, et al.Electrical Energy Density and Dielectric Properties of Poly(vinylidene fluoride- chlorotrifluoroethylene)/BaSrTiO3 Nanocomposites[J]. Ceramics International, 2012, 38(2): 1071-1075.
Funding
The Programs for Tackling Key Problems in Science and Technology of Henan Province (252102231014, 262102231004); The Innovation Training Program for College Students in Henan Province (202611517001); Key scientific research projects of colleges and universities in Henan Province (26A430004)
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