Submit to Materials Review for Materials Propose a Special Issue

Journal Browser

► Journal Browser

Novel Dielectric Materials: Innovations and Applications

Print Special Issue Flyer
Special Issue Editors
Special Issue Information
Keywords
Related Special Issue
Published Papers

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Electronic Materials".

Deadline for manuscript submissions: closed (30 June 2022) | Viewed by 15494

Share This Special Issue

Special Issue Editor

Prof. Dr. Junwei Zha

E-Mail Website
Guest Editor

Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China
Interests: nanodielectrics; dielectric properties; energy storage; thermal management; insulation materials; smart materials
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Human society is becoming more and more dependent on electricity. Thus, based on the capability of controlling/storing charge and electrical energy, dielectric materials have attracted great attention. Examples of these materials, all of which require tailored dielectric properties, include high-permittivity (k) materials for capacitors, low-k materials for 5G and transformers, dielectric elastomers for electroactive generators/actuators, thermally conductive materials for high-voltage packing, and flexible/biological materials for intelligent devices.

Therefore, a comprehensive understanding of the chemistry and physics, the surfaces and interfaces, and the composition and microstructure of dielectric materials will be extremely important. Research on polarization mechanisms, technologies of material preparation, and even novel detection methods is needed to develop the means of adjusting and controlling dielectric materials.

The aim of this Special Issue of Materials is to attract articles covering any aspects of new dielectric materials, including material development, microstructural optimization, and novel implant designs. We welcome original research work, communications, or reviews with a clear focus on these areas.

Prof. Dr. Junwei Zha
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

dielectric materials
nanodielectrics
dielectric properties
electrical properties
thermal properties
high-voltage electrical insulation
smart dielectrics

Related Special Issue

Novel Dielectric Materials: Innovations and Applications—Volume II in Materials

Published Papers (7 papers)

Download All Papers

Research

20 pages, 4284 KiB

Open AccessArticle

Influence of Emerging Semiconductive Nanoparticles on AC Dielectric Strength of Synthetic Ester Midel-7131 Insulating Oil

by Muhammad Fasehullah, Feipeng Wang, Sidra Jamil and Muhammad Shoaib Bhutta

Materials 2022, 15(13), 4689; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15134689 - 04 Jul 2022

Cited by 6 | Viewed by 1424

Abstract

Exploring impressively effective dielectric nanofluids for transformers to improve dielectric strength and thermal stability is indispensable. It is crucial to determine the modification mechanism of dispersed nanomaterials in insulating oil for operative applications in power transformers. This paper aspires to authenticate the experimental evidence of the enhancing AC dielectric strength of synthetic ester Midel-7131 using two newly introduced semiconductive nanoparticles, CdS and Co₃O₄, and uncover the potential reasons for enhanced AC dielectric strength. The AC breakdown voltage (BDV) of synthetic ester and nanofluids was investigated and statistically evaluated. The mean AC breakdown voltage of SE/CdS and SE/Co₃O₄ was increased by 31.9% and 31.3%, respectively. The augmentation in AC breakdown strength is possibly due to the facilitated charge-scavenging ability owing to the large specific surface area and wide bandgap. Simultaneous thermogravimetric analysis, differential scanning calorimetry, and derivative thermogravimetry analyses (TGA–DSC–DTG) confirmed that the initial decomposition temperature was high and heat dissipation was low, indicating that the nanofluids were thermally stable in both air and nitrogen. Hence, emerging semiconductive CdS and Co₃O₄-based nanofluids of synthetic ester possess remarkable dielectric strength and thermal stability enhancement for their application in power transformers. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures

Figure 1

15 pages, 4903 KiB

Open AccessArticle

Impedance and Dielectric Properties of PVC:NH₄I Solid Polymer Electrolytes (SPEs): Steps toward the Fabrication of SPEs with High Resistivity

by Muaffaq M. Nofal, Shujahadeen B. Aziz, Hewa O. Ghareeb, Jihad M. Hadi, Elham M. A. Dannoun and Sameerah I. Al-Saeedi

Materials 2022, 15(6), 2143; https://0-doi-org.brum.beds.ac.uk/10.3390/ma15062143 - 15 Mar 2022

Cited by 9 | Viewed by 2036

Abstract

In the present article, a simple technique is provided for the fabrication of a polymer electrolyte system composed of polyvinyl chloride (PVC) and doped with varying content of ammonium iodide (NH₄I) salt using solution-casting methodology. The influences of NH₄I on the structural, electrochemical, and electrical properties of PVC have been investigated using X-ray diffraction, electrochemical impedance spectroscopy (EIS), and dielectric properties. The X-ray study reveals the amorphous nature of the polymer–salt complex. The EIS measurement revealed an ionic conductivity of 5.57 × 10⁻¹⁰ S/cm for the electrolyte containing 10 wt.% of salt. Our hypothesis is provided, which demonstrated the likelihood of designing highly resistive solid electrolytes using the concept of a polymer electrolyte. Here, the results showed that the resistivity of the studied samples is not dramatically decreased with increasing NH₄I. Bode plots distinguish the decrease in resistance or impedance with increasing salt contents. Dielectric measurements revealed a decrease in the dielectric constant with the increase of NH₄I content in the PVC polymer. The relaxation time and dielectric properties of the electrolytes confirmed their non-Debye type behavior. This pattern has been validated by the existence of an incomplete semicircle in the Argand plot. Insulation materials with low ε_r have found widespread applications in electronic devices due to the reduction in delay, power dissipation, and crosstalk. In addition, an investigation of real and imaginary parts of electric modulus leads to the minimized electrode polarization being reached. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures

Figure 1

9 pages, 2351 KiB

Open AccessArticle

Direct Evidence of Ice Crystallization Inhibition by Dielectric Relaxation of Hydrated Ions

by Xiaoyuan Song, Lisheng Zhong and Jinghui Gao

Materials 2021, 14(22), 6975; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14226975 - 18 Nov 2021

Cited by 7 | Viewed by 1572

Abstract

In this paper, the inhibition effect of an alternative current (AC) electric field on ice crystallization in 0.9 wt % NaCl aqueous solution was confirmed thermodynamically with characterization. An innovative experimental and analytical method, combining differential scanning calorimeter (DSC) measurement with an externally applied electric field was created by implanting microelectrodes in a sample crucible. It was found that the ice crystallization, including pure ice and salty ice, was obviously inhibited after field cooling with an external AC electric field in a frequency range of 100 k–10 MHz, and the crystallization ratio was related to frequency. Compared with non-field cooling, the crystallization ratio of ice crystals was reduced to less than 20% when E = 57.8 kV/m and f = 1 MHz. The dielectric spectrum results show that this inhibition effect of an alternating electric field on ice crystal growth is closely related to the dielectric relaxation process of hydrated ions. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures

Figure 1

9 pages, 2591 KiB

Open AccessArticle

Low—Permittivity Copolymerized Polyimides with Fluorene Rigid Conjugated Structure

by Xiaodi Dong, Mingsheng Zheng, Baoquan Wan, Xuejie Liu, Haiping Xu and Junwei Zha

Materials 2021, 14(21), 6266; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14216266 - 21 Oct 2021

Cited by 11 | Viewed by 2032

Abstract

As the miniaturization of electronic appliances and microprocessors progresses, low-permittivity interlayer materials are becoming increasingly important for their suppression of electronic crosstalk, signal propagation delay and loss, and so forth. Herein, a kind of copolyimide (CPI) film with a “fluorene” rigid conjugated structure was prepared successfully. By introducing 9,9-Bis(3-fluoro-4-aminophenyl) fluorene as the rigid conjugated structure monomer, a series of CPI films with different molecular weights were fabricated by in situ polymerization, which not only achieved the reduction of permittivity but also maintained excellent thermodynamic stability. Moreover, the hydrophobicity of the CPI film was also improved with the increasing conjugated structure fraction. The lowest permittivity reached 2.53 at 10⁶ Hz, while the thermal decomposition temperature (T_d5%) was up to 530 °C, and the tensile strength was ≥ 96 MPa. Thus, the CPI films are potential dielectric materials for microelectronic and insulation applications. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures

Figure 1

11 pages, 2954 KiB

Open AccessArticle

Synergistic Enhanced Thermal Conductivity and Dielectric Constant of Epoxy Composites with Mesoporous Silica Coated Carbon Nanotube and Boron Nitride Nanosheet

by Yutao Hao, Qihan Li, Xianhai Pang, Bohong Gong, Chengmei Wei and Junwen Ren

Materials 2021, 14(18), 5251; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14185251 - 13 Sep 2021

Cited by 8 | Viewed by 1957

Abstract

Dielectric materials with high thermal conductivity and outstanding dielectric properties are highly desirable for advanced electronics. However, simultaneous integration of those superior properties for a material remains a daunting challenge. Here, a multifunctional epoxy composite is fulfilled by incorporation of boron nitride nanosheets (BNNSs) and mesoporous silica coated multi-walled carbon nanotubes (MWCNTs@mSiO₂). Owing to the effective establishment of continuous thermal conductive network, the obtained BNNSs/MWCNTs@mSiO₂/epoxy composite exhibits a high thermal conductivity of 0.68 W m⁻¹ K⁻¹, which is 187% higher than that of epoxy matrix. In addition, the introducing of mesoporous silica dielectric layer can screen charge movement to shut off leakage current between MWCNTs, which imparts BNNSs/MWCNTs@mSiO₂/epoxy composite with high dielectric constant (8.10) and low dielectric loss (<0.01) simultaneously. It is believed that the BNNSs/MWCNTs@mSiO₂/epoxy composites with admirable features have potential applications in modern electronics. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures

Figure 1

10 pages, 3794 KiB

Open AccessArticle

Polymer Nanocomposites with High Energy Density Utilizing Oriented Nanosheets and High-Dielectric-Constant Nanoparticles

by Yushu Li, Yao Zhou, Sang Cheng, Jun Hu, Jinliang He and Qi Li

Materials 2021, 14(17), 4780; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14174780 - 24 Aug 2021

Cited by 9 | Viewed by 1823

Abstract

The development of high-energy-density electrostatic capacitors is critical to addressing the growing electricity need. Currently, the widely studied dielectric materials are polymer nanocomposites incorporated with high-dielectric-constant nanoparticles. However, the introduction of high-dielectric-constant nanoparticles can cause local electric field distortion and high leakage current, which limits the improvement in energy density. In this work, on the basis of conventional polymer nanocomposites containing high-dielectric-constant nanoparticles, oriented boron nitride nanosheets (BNNSs) are introduced as an extra filler phase. By changing the volume ratios of barium titanate (BT) and BNNSs, the dielectric property of polymer nanocomposites is adjusted, and thus the capacitive energy storage performance is optimized. Experimental results prove that the oriented BNNSs can suppress the propagation of charge carriers and decrease the conduction loss. Using poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-HFP)) as the polymer matrix, the P(VDF-HFP)/BNNS/BT nanocomposite has a higher discharged energy density compared with the conventional nanocomposite with the freely dispersed BT nanoparticles. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures

Figure 1

12 pages, 7800 KiB

Open AccessArticle

Construction of a Three-Dimensional BaTiO₃ Network for Enhanced Permittivity and Energy Storage of PVDF Composites

by Xueqing Bi, Lujia Yang, Zhen Wang, Yanhu Zhan, Shuangshuang Wang, Chunmei Zhang, Yuchao Li, Yinggang Miao and Junwei Zha

Materials 2021, 14(13), 3585; https://0-doi-org.brum.beds.ac.uk/10.3390/ma14133585 - 27 Jun 2021

Cited by 18 | Viewed by 2644

Abstract

Three-dimensional BaTiO₃ (3D BT)/polyvinylidene fluoride (PVDF) composite dielectrics were fabricated by inversely introducing PVDF solution into a continuous 3D BT network, which was simply constructed via the sol-gel method using a cleanroom wiper as a template. The effect of the 3D BT microstructure and content on the dielectric and energy storage properties of the composites were explored. The results showed that 3D BT with a well-connected continuous network and moderate grain sizes could be easily obtained by calcining a barium source containing a wiper template at 1100 °C for 3 h. The as-fabricated 3D BT/PVDF composites with 21.1 wt% content of 3D BT (3DBT–2) exhibited the best comprehensive dielectric and energy storage performances. An enhanced dielectric constant of 25.3 at 100 Hz, which was 2.8 times higher than that of pure PVDF and 1.4 times superior to the conventional nano–BT/PVDF 25 wt% system, was achieved in addition with a low dielectric loss of 0.057 and a moderate dielectric breakdown strength of 73.8 kV·mm⁻¹. In addition, the composite of 3DBT–2 exhibited the highest discharge energy density of 1.6 × 10⁻³ J·cm⁻³ under 3 kV·mm⁻¹, which was nearly 4.5 times higher than that of neat PVDF. Full article

(This article belongs to the Special Issue Novel Dielectric Materials: Innovations and Applications)

► Show Figures