Dielectric Spectroscopy of Polymer-Based Nanocomposite Dielectrics with Tailored Interfaces and Structured Spatial Distribution of Fillers

Polizos, Georgios; Tuncer, Enis; Tomer, V.; Sauers, I.; Randall, Clive A.; Manias, Evangelos

doi:10.1201/b15615-4

Cited by 9 publications

(6 citation statements)

References 59 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The imaginary part of the complex electric modulus, M *(ω) = M ′(ω) + iM ′′(ω) is depicted in the inset of Figure at −104 °C for each of the BMPyrDCA hydration levels and will be analyzed with an equivalent of the HN equation (eq ) given by italicM normal* ( ω ) = M ∞ + normalΔ M ( 1 + false( prefix− 1 false( ω τ HN − normalM false) − 1 false) β HN ) γ HN which is widely used to suppress conductivity and polarization phenomena and to reveal the dipolar contributions …”

Section: Dielectric Characterizationmentioning

confidence: 99%

Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids

et al. 2014

View full text Add to dashboard Cite

The thermal behavior and transport properties of several ion jellys (IJs), a composite that results from the combination of gelatin with an ionic liquid (IL), were investigated by dielectric relaxation spectroscopy (DRS), differential scanning calorimetry (DSC), and pulsed field gradient nuclear magnetic resonance spectroscopy (PFG NMR). Four different ILs containing the dicyanamide anion were used: 1-butyl-3-methylimidazolium dicyanamide (BMIMDCA), 1-ethyl-3-methylimidazolium dicyanamide (EMIMDCA), 1-butyl-1-methylpyrrolidinium dicyanamide (BMPyrDCA), and 1-butylpyridinium dicyanamide (BPyDCA); the bulk ILs were also investigated for comparison. A glass transition was detected by DSC for all materials, ILs and IJs, allowing them to be classified as glass formers. Additionally, an increase in the glass transition temperature upon dehydration was observed with a greater extent for IJs, attributed to a greater hindrance imposed by the gelatin matrix after water removal, rendering the IL less mobile. While crystallization is observed for some ILs with negligible water content, it was never detected for any IJ upon thermal cycling, which persist always as fully amorphous materials. From DRS measurements, conductivity and diffusion coefficients for both cations (D+) and anions (D-) were extracted. D+ values obtained by DRS reveal excellent agreement with those obtained from PFG NMR direct measurements, obeying the same VFTH equation over a large temperature range (ΔT ≈ 150 K) within which D+ varies around 10 decades. At temperatures close to room temperature, the IJs exhibit D values comparable to the most hydrated (9%) ILs. The IJ derived from EMIMDCA possesses the highest conductivity and diffusion coefficient, respectively, ∼10(-2) S·cm(-1) and ∼10(-10) m(2)·s(-1). For BMPyrDCA the relaxational behavior was analyzed through the complex permittivity and modulus formalism allowing the assignment of the detected secondary relaxation to a Johari-Goldstein process. Besides the relevant information on the more fundamental nature providing physicochemical details on ILs behavior, new doorways are opened for practical applications by using IJ as a strategy to produce novel and stable electrolytes for different electrochemical devices.

show abstract

Section: Dielectric Characterizationmentioning

confidence: 99%

Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Characterization of frequency and temperature dependent dielectric and electrical properties of the polymer nanocomposite (PNC) materials has been one of the intense areas of research in the advances of materials science and engineering [1][2][3][4][5][6]. These PNC materials are broadly used as flexible nanodielectric substrate and an electrical insulator for the organic thin film transistors [5][6][7], transient electronic antennas [8], packaging for electronic devices [9,10], electromagnetic pollution and interference shielding [11], as a base matrix for the preparation of optoelectronic devices [12], sensors [13], and solid-state energy storage and conversion devices [14].…”

Section: Introductionmentioning

confidence: 99%

“…The PNC materials comprise most of the useful properties of inorganic nanofiller and the host polymer matrix. The electrostatic interactions between the nanoparticles and the functional groups of the polymer chain, and also their physical interfaces play an important role in the settlement of dielectric, electrical, and physicochemical properties of the PNCs [1,4,5,15]. For several PNC materials, their dielectric and electrical properties can be tailored by selecting a suitable dielectric permittivity value polymer matrix, inorganic nanofiller and its electronic nature of surface, concentration of polymer and filler in the composition, and also the use of an appropriate nanocomposite preparation method.…”

Section: Introductionmentioning

confidence: 99%

Structural, morphological, thermal, dielectric, and electrical properties of alumina nanoparticles filled PVA–PVP blend matrix‐based polymer nanocomposites

Choudhary

2018

Polymer Composites

View full text Add to dashboard Cite

Alumina (Al2O3) nanoparticles filled poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) blend matrix (50/50 wt%) based polymer nanocomposite (PNC) films (i.e., [PVA–PVP]–x wt% Al2O3; x = 0, 1, 3, and 5) have been prepared by solution‐cast method. X‐ray diffraction study has confirmed that the structures of these PNC materials are predominantly amorphous. The formation of miscible blend, polymer–polymer and polymer–nanoparticle interactions, and the effect of Al2O3 nanoparticles on the thermal properties of PVA–PVP blend matrix have been examined by Fourier transform infrared, differential scanning calorimetry and scanning electron microscopy measurements of the PNC films. The dielectric and electrical spectra of these PNC films have been measured from 20 Hz to 1 MHz using dielectric relaxation spectroscopy. It has been found that the dispersion of merely 1 wt% Al2O3 nanoparticles in the PVA–PVP blend matrix significantly reduces the crystalline phase and enhance the melting phase transition temperature of the PNC material, while the dielectric permittivity greatly decrease due to nano confinement effect. The real parts of dielectric permittivity and the impedance of these PNC films decrease linearly with the increase of the frequency, whereas the ac electrical conductivity has increased. A nonlinear increase of dielectric permittivity has been found with an increase of the temperature of PNC film and its dc electrical conductivity obeys the Arrhenius behavior. The dielectric and electrical properties of these PNC materials confirm their suitability as flexible nanodielectric of frequency tunable permittivity. POLYM. COMPOS., 39:E1788–E1799, 2018. © 2018 Society of Plastics Engineers

show abstract

“…The pristine PEO/LiTFSI electrolyte is characterized by a bimodal relaxation mechanism and a low frequency power law contribution due to conductivity and polarization effects. Least-square fitting analysis to the dielectric spectra was performed by using a superposition of two Havriliak–Negami (HN) expressions and a power law contribution to simulate the low frequency conductivity process. − The permittivity analysis method is described in the Experimental Section. The low and high frequency peaks of the pristine PEO/LiTFSI electrolyte in Figure correspond to mechanisms with slower and faster dynamics, respectively (the relaxation time is inversely proportional to the frequency).…”

Section: Resultsmentioning

confidence: 99%

Nanoscale Ion Transport Enhances Conductivity in Solid Polymer-Ceramic Lithium Electrolytes

Polizos,

Goswami,

Keum

et al. 2024

ACS Nano

View full text Add to dashboard Cite

The predictive design of flexible and solvent-free polymer electrolytes for solid-state batteries requires an understanding of the fundamental principles governing the ion transport. In this work, we establish a correlation among the composite structures, polymer segmental dynamics, and lithium ion (Li + ) transport in a ceramic-polymer composite. Elucidating this structure−property relationship will allow tailoring of the Li + conductivity by optimizing the macroscopic electrochemical stability of the electrolyte. The ion dissociation from the slow polymer segmental dynamics was found to be enhanced by controlling the morphology and functionality of the polymer/ ceramic interface. The chemical structure of the Li + salt in the composite electrolyte was correlated with the size of the ionic cluster domains, the conductivity mechanism, and the electrochemical stability of the electrolyte. Polyethylene oxide (PEO) filled with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) or lithium bis(fluorosulfonyl) imide (LiFSI) salts was used as a matrix. A garnet electrolyte, aluminum substituted lithium lanthanum zirconium oxide (Al-LLZO) with a planar geometry, was used for the ceramic nanoparticle moieties. The dynamics of the strongly bound and highly mobile Li + were investigated using dielectric relaxation spectroscopy. The incorporation of the Al-LLZO platelets increased the number density of more mobile Li + . The structure of the nanoscale ion-agglomeration was investigated by small-angle X-ray scattering, while molecular dynamics (MD) simulation studies were conducted to obtain the fundamental mechanism of the decorrelation of the Li + in the LiTFSI and LiFSI salts from the long PEO chain.

show abstract

Dielectric Spectroscopy of Polymer-Based Nanocomposite Dielectrics with Tailored Interfaces and Structured Spatial Distribution of Fillers

Cited by 9 publications

References 59 publications

Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids

Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids

Structural, morphological, thermal, dielectric, and electrical properties of alumina nanoparticles filled PVA–PVP blend matrix‐based polymer nanocomposites

Nanoscale Ion Transport Enhances Conductivity in Solid Polymer-Ceramic Lithium Electrolytes

Contact Info

Product

Resources

About