Size effects of graphene nanoplatelets on the properties of high-density polyethylene nanocomposites: morphological, thermal, electrical, and mechanical characterization

• Tuba Evgin,
• Alpaslan Turgut,
• Georges Hamaoui,
• Zdenko Spitalsky,
• Nicolas Horny,
• Matej Micusik,
• Mihai Chirtoc,
• Mehmet Sarikanat and
• Maria Omastova

Beilstein J. Nanotechnol. 2020, 11, 167–179, doi:10.3762/bjnano.11.14

• –85°, with a scanning speed of 0.03°/s. FTIR measurements were carried out with a Thermo Fisher Scientific iS10 infrared spectrometer in the range of 4000–650 cm−1 at room temperature. Broadband dielectric spectroscopy (BDS) measurements were conducted using a Novocontrol Concept 40 instrument with an

Advanced hybrid nanomaterials

• Andreas Taubert,
• Fabrice Leroux,
• Pierre Rabu and
• Verónica de Zea Bermudez

Beilstein J. Nanotechnol. 2019, 10, 2563–2567, doi:10.3762/bjnano.10.247

• fire retardancy and gas permeation in a low molecular weight epoxy resin [28]. Regarding specific applications, the dielectric properties were investigated by broadband dielectric spectroscopy (BDS) in “Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic

Nanocomposite–parylene C thin films with high dielectric constant and low losses for future organic electronic devices

• Marwa Mokni,
• Gianluigi Maggioni,
• Abdelkader Kahouli,
• Sara M. Carturan,
• Walter Raniero and
• Alain Sylvestre

Beilstein J. Nanotechnol. 2019, 10, 428–441, doi:10.3762/bjnano.10.42

• with various contents and sizes of silver-oxide nanoparticles were investigated by broadband dielectric spectroscopy (BDS) in view of their final application. It was found that both the content and the size of the nanoparticles influence the value of the dielectric constant and the frequency-dependence

• experimental techniques. Particularly, in order to evaluate the effect of the Ag-containing nanofiller charges regarding a possible integration as gate insulating material for OFETs, broadband dielectric spectroscopy (BDS) is carried out on NCPCs with different content of silver-containing nanoparticles. As a

• properties were measured using a Novocontrol broadband dielectric spectroscopy (BDS20) impedance meter in the frequency range of 0.1–106 Hz at room temperature. Ag dose (left) and film thickness (right) versus rotations. Film thickness versus RBS thickness (see text for details). Blue and red squares data

Threshold voltage decrease in a thermotropic nematic liquid crystal doped with graphene oxide flakes

• Mateusz Mrukiewicz,
• Krystian Kowiorski,
• Paweł Perkowski,
• Rafał Mazur and
• Małgorzata Djas

Beilstein J. Nanotechnol. 2019, 10, 71–78, doi:10.3762/bjnano.10.7

• dielectric spectroscopy measurements. The effect is related to the disrupted planar alignment due to the strong π–π stacking between the 5CB’s benzene rings and the graphene oxide’s structure. Additionally, we present the GO concentration dependence on the isotropic–nematic phase transition temperature

• oscilloscope (Tektronix TDS 2014) was used to register the electro-optical response. The duration of the driving pulse was 1 s. Dielectric spectroscopy (DS) studies were performed using an impedance analyzer (Agilent 4294A) and conducted over a broad frequency range from 100 Hz to 10 MHz, with the oscillation

• 0.1 wt %, the GO flakes disturb the formation of the nematic phase. In this experiment, the Frédericksz transition was induced by the electric field. The threshold voltage dependence on the GO concentration in 5CB was investigated by two methods: an electro-optic (EO) and dielectric spectroscopy (DS

Electrostatic force microscopy for the accurate characterization of interphases in nanocomposites

• Diana El Khoury,
• Richard Arinero,
• Jean-Charles Laurentie,
• Mikhaël Bechelany,
• Michel Ramonda and
• Jérôme Castellon

Beilstein J. Nanotechnol. 2018, 9, 2999–3012, doi:10.3762/bjnano.9.279

• , the authors hypothesized that an interphase with lower permittivity than that of particles and fillers surrounds the particles. However, the authors did not compare this remarkable change in local dielectric permittivity with macroscopic dielectric spectroscopy measurements. Nevertheless, the

Formation and development of nanometer-sized cybotactic clusters in bent-core nematic liquid crystalline compounds

• Yuri P. Panarin,
• Sithara P. Sreenilayam,
• Jagdish K. Vij,
• Anne Lehmann and
• Carsten Tschierske

Beilstein J. Nanotechnol. 2018, 9, 1288–1296, doi:10.3762/bjnano.9.121

• , Institute of Chemistry, Martin Luther University Halle-Wittenberg, 06120 Halle, Germany 10.3762/bjnano.9.121 Abstract Two homologue achiral bent-core liquid crystals (LCs), BCN66 and BCN84, in their nematic phases are studied by dielectric spectroscopy in the frequency range 10 Hz–10 MHz. In each of these

• and volume fraction and give rise to sharp cluster boundaries. The findings confirm that dielectric spectroscopy is a powerful and an extremely useful technique to provide a deeper understanding of the mechanism of cybotactic cluster formation in the isotropic liquid and the nematic phase of LCs as a

• function of temperature and the bias field. Keywords: bent-core liquid crystals; biaxiality; clusters; dielectric spectroscopy; Introduction Biaxial liquid crystals (LCs) exhibit supramolecular structures with long-range orientational ordering of the long and the short molecular axes but without a long

Nanoscale mapping of dielectric properties based on surface adhesion force measurements

• Ying Wang,
• Yue Shen,
• Xingya Wang,
• Zhiwei Shen,
• Bin Li,
• Jun Hu and
• Yi Zhang

Beilstein J. Nanotechnol. 2018, 9, 900–906, doi:10.3762/bjnano.9.84

• dielectric properties of nanomaterials, such as electrostatic force microscopy [16][17][18][19], scanning polarization force microscopy (SPFM) [20][21][22][23], local dielectric spectroscopy [24][25][26], and nanoscale capacitance microscopy [27][28][29]. Most of the proposed techniques are based on long

Design of polar self-assembling lactic acid derivatives possessing submicrometre helical pitch

• Alexej Bubnov,
• Cyril Vacek,
• Michał Czerwiński,
• Terezia Vojtylová,
• Wiktor Piecek and
• Věra Hamplová

Beilstein J. Nanotechnol. 2018, 9, 333–341, doi:10.3762/bjnano.9.33

• electro-optic and dielectric spectroscopy. The materials possess a self-assembling behaviour on the nanoscale level as they form polar smectic liquid crystalline mesophases, namely the orthogonal paraelectric SmA* and the tilted ferroelectric SmC* phases, in a broad temperature range down to room

• promoting opposite handedness, as described in [49]. The values of the helical pitch length considerably decrease with the decrease of both alkyl chain lengths while comparing to the results obtained on similar compounds [20][37][40]. Dielectric spectroscopy For the two selected materials, illustrative

• , revealed by the broad-band dielectric spectroscopy, with respect to the mixture composition, is beyond the scope of the present work and will be presented elsewhere. Conclusion Several chiral liquid crystalline materials possessing two ester groups in the molecular core and the non-chiral alkyl chain

Dielectric properties of a bisimidazolium salt with dodecyl sulfate anion doped with carbon nanotubes

• Doina Manaila Maximean,
• Viorel Cîrcu and
• Constantin Paul Ganea

Beilstein J. Nanotechnol. 2018, 9, 164–174, doi:10.3762/bjnano.9.19

• low frequencies confirm the presence of EP. Keywords: activation energy; carbon nanotubes; dielectric spectroscopy; ionic liquid crystal; relaxation time; Introduction Ionic liquid crystals (ILCs) represent a very appealing class of materials that has found various recent applications in dye

• ][39][40][41][42][43][44]. There are studies dedicated to the dielectric spectroscopy (DS) of ILCs doped with CNT [45]. In the present work we studied the effect of added CNTs on the dielectric properties of a new ILC based on a bisimidazolium salt with a dodecyl sulfate ion. The dielectric spectra of

• interdigitated double layer structure for the SmA mesophase [4][20]. Dielectric spectroscopy The DS measurements were performed both for the pure ILC and for various mixtures of CNT-doped ILC (concentration 0.05% w/w and 0.5% w/w) in the frequency range from 10−1 to 107 Hz. The temperature range was chosen in

Electrical properties of a liquid crystal dispersed in an electrospun cellulose acetate network

• Doina Manaila Maximean,
• Octavian Danila,
• Pedro L. Almeida and
• Constantin Paul Ganea

Beilstein J. Nanotechnol. 2018, 9, 155–163, doi:10.3762/bjnano.9.18

• techniques, such as polarized optical microscopy, dielectric spectroscopy and impedance measurements. Dielectric constant and electric energy loss were studied as a function of frequency and temperature. The activation energy was evaluated and the relaxation time was obtained by fitting the spectra of the

• dielectric loss with the Havriliak–Negami functions. To determine the electrical characteristics of the studied samples, impedance measurements results were treated using the Cole–Cole diagram and the three-element equivalent model. Keywords: cellulose nanocomposite; dielectric spectroscopy; impedance

• investigations of the electrical properties of an electrospun CA network with dispersed liquid crystals. Dielectric spectroscopy (DS) was performed over wide ranges of frequency and temperature to determine physical properties such as activation energy and characteristic time. The experimental results of DS were

Single-pass Kelvin force microscopy and dC/dZ measurements in the intermittent contact: applications to polymer materials

• Sergei Magonov and
• John Alexander

Beilstein J. Nanotechnol. 2011, 2, 15–27, doi:10.3762/bjnano.2.2

• with dielectric spectroscopy [18], were studied with AFM probe at a single location. Furthermore, these studies were extended to dC/dZ mapping of a PVAC/PS blend at different temperatures in UHV [19] and to studies of a PVAC-based nanocomposite material [20]. We initiated KFM and dC/dZ measurements of

• of these studies to a broad frequency range and at different temperatures will be essential for reliable interpretation of the dielectric data and will be the subject of nanoscale dielectric spectroscopy. Sketch illustrating implementation of Kelvin force microscopy in the AM–FM mode. Two servo-loops