Polymer nanoparticles from low-energy nanoemulsions for biomedical applications

• Santiago Grijalvo and
• Carlos Rodriguez-Abreu

Beilstein J. Nanotechnol. 2023, 14, 339–350, doi:10.3762/bjnano.14.29

• , the system passes through structures with zero curvature, such as bicontinuous microemulsions or flexible lamellar liquid crystals [15]. The PIC method is amenable for scaling up since it mainly involves a simple dilution process and is suitable for components that cannot withstand high temperatures

Tunable high-quality-factor absorption in a graphene monolayer based on quasi-bound states in the continuum

• Jun Wu,
• Yasong Sun,
• Feng Wu,
• Biyuan Wu and
• Xiaohu Wu

Beilstein J. Nanotechnol. 2022, 13, 675–681, doi:10.3762/bjnano.13.59

• change the structural parameters and the other is to add tunable materials, such as phase change materials, graphene, or liquid crystals. Among them, graphene has attracted much attention in optics and optoelectronics [30][31][32][33][34]. As a single layer of carbon atoms arranged in a honeycomb

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

Uniform arrays of gold nanoelectrodes with tuneable recess depth

• Elena O. Gordeeva,
• Ilya V. Roslyakov,
• Alexey P. Leontiev,
• Alexey A. Klimenko and
• Kirill S. Napolskii

Beilstein J. Nanotechnol. 2021, 12, 957–964, doi:10.3762/bjnano.12.72

• alternative approach includes bulk electrode structuring by deposition or etching techniques using self-assembled arrays of colloidal nanoparticles [15], liquid crystals [16], or track-etched membranes [17][18][19] as template or mask, respectively. Among porous templates, anodic aluminium oxide (AAO) allows

Optically and electrically driven nanoantennas

• Monika Fleischer,
• Dai Zhang and
• Alfred J. Meixner

Beilstein J. Nanotechnol. 2020, 11, 1542–1545, doi:10.3762/bjnano.11.136

• a TERS setup, which has been rarely pursued so far. In the hot topic area of active plasmonics, reversible changes in the refractive index of the environment of a plasmonic system, for example, by liquid crystals or thermosensitive polymers, allow for actively switching the plasmonic properties [50

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• only by a length variation but also by a significant change of the dipole moment [33][34]. Azobenzenes were used in various materials namely as liquid crystals, optical switches or for data storage [35][36]. Because of the chemical and physical changes associated with the switching process, the

Design of a nanostructured mucoadhesive system containing curcumin for buccal application: from physicochemical to biological aspects

• Sabrina Barbosa de Souza Ferreira,
• Gustavo Braga,
• Évelin Lemos Oliveira,
• Jéssica Bassi da Silva,
• Hélen Cássia Rosseto,
• Lidiane Vizioli de Castro Hoshino,
• Mauro Luciano Baesso,
• Wilker Caetano,
• Craig Murdoch,
• Helen Elizabeth Colley and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2019, 10, 2304–2328, doi:10.3762/bjnano.10.222

• characteristics beneficial for pharmaceutical and biomedical use [1]. P407 is a non-ionic block copolymer with polypropylene oxide (PPO) and polyethylene oxide (PEO) segments, which can display thermoresponsive properties forming nanometer-sized micelles, hydrogels and lyotropic liquid crystals [2][3]. The

Liquid crystal tunable claddings for polymer integrated optical waveguides

• José M. Otón,
• Manuel Caño-García,
• Fernando Gordo,
• Eva Otón,
• Morten A. Geday and
• Xabier Quintana

Beilstein J. Nanotechnol. 2019, 10, 2163–2170, doi:10.3762/bjnano.10.209

• . These elements could contribute to the integrated circuit functionality if they were modulated either by variations of the core optical properties, or by using tunable claddings. In this work, the use of liquid crystals as electro-optically active claddings for driving integrated waveguides has been

• between core and cladding. In this work, the use of liquid crystals (LCs) as tunable claddings of waveguides has been explored. Given the range of refractive indices shown by LCs, the use of standard inorganic core materials is unfeasible. Instead, a number of organic cores have been tested. Results and

• for a number of reasons. Developments fostering the PIC functionality without increasing its complexity are a possible way to contribute to new PIC realizations. Passive waveguides can contribute to managing guided optical signals by making them tunable using electrooptically active claddings. Liquid

Precise local control of liquid crystal pretilt on polymer layers by focused ion beam nanopatterning

• Maxim V. Gorkunov,
• Irina V. Kasyanova,
• Vladimir V. Artemov,
• Alena V. Mamonova and
• Serguei P. Palto

Beilstein J. Nanotechnol. 2019, 10, 1691–1697, doi:10.3762/bjnano.10.164

• Institute), 115409 Moscow, Russia 10.3762/bjnano.10.164 Abstract Background: The alignment of liquid crystals by surfaces is crucial for applications. It determines the director configuration in the bulk, its stability against defects and electro-optical switching scenarios. The conventional planar

Magnetic segregation effect in liquid crystals doped with carbon nanotubes

• Danil A. Petrov,
• Pavel K. Skokov,
• Alexander N. Zakhlevnykh and
• Dmitriy V. Makarov

Beilstein J. Nanotechnol. 2019, 10, 1464–1474, doi:10.3762/bjnano.10.145

• tricritical behavior is related to the redistribution of the carbon nanotubes (segregation effect) inside the layer. Keywords: carbon nanotubes; liquid crystal; magnetic field; orientational transitions; segregation effect; Introduction Composites of liquid crystals (LCs) and nanoparticles are actively

• modifies many properties of liquid crystals and leads to the possibility of obtaining new hybrid materials with unique electro- and magneto-optical properties, which opens prospects for new practical applications in optoelectronics, photonics, and display technology [11]. From a physical perspective, these

• feature of CNTs is their strong diamagnetism ( ≈ 10−5 to 10−4) [18][19][20][21][22][23]. In the majority of experimental publications [7][16][24][25][26] the planar type of anchoring between the nanotubes and the LC matrix is noted. For CNT suspensions based on nematic liquid crystals (NLCs) with positive

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

• presence of the electric field was discussed. Keywords: graphene oxide; liquid crystal; nematic phase; switching; threshold voltage; Introduction Liquid crystals (LCs) are classified as a type of soft matter which are characterized by anisotropic molecules and a liquid-like fluidity behavior. Of all LC

• permittivity measured along the directions parallel and perpendicular to n, respectively. In the case of positive electric anisotropy (Δε > 0), the director is forced to align along the electric field. One of the most efficient methods to reduce the threshold voltage in nematic liquid crystals for high electro

• areas. Therefore, the main advantage of GO is easy dispersibility in water and organic solvents [23][25]. Graphene oxide occurs in the form of two-dimensional flakes with anisotropic properties [24]. In thermotropic nematic liquid crystals, GO flakes create dipoles due to Maxwell–Wagner polarization [26

Polarization-dependent strong coupling between silver nanorods and photochromic molecules

• Gwénaëlle Lamri,
• Alessandro Veltri,
• Jean Aubard,
• Pierre-Michel Adam,
• Nordin Felidj and
• Anne-Laure Baudrion

Beilstein J. Nanotechnol. 2018, 9, 2657–2664, doi:10.3762/bjnano.9.247

• approaches have been explored to actively control these plasmonic properties without changing the topographic features of the nanoparticles themselves. Liquid crystals [5], thermosensitive polymers [6], transition metal dichalcogenides [7] and graphene [8] monolayers have been used for this purpose. The

Nanostructured liquid crystal systems and applications

• Alexei R. Khokhlov and
• Alexander V. Emelyanenko

Beilstein J. Nanotechnol. 2018, 9, 2644–2645, doi:10.3762/bjnano.9.245

• Alexei R. Khokhlov Alexander V. Emelyanenko Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory, Moscow 119991, Russia 10.3762/bjnano.9.245 Keywords: artificial muscles; displays; energy saving; liquid crystals; photoinduction; sensors; Liquid crystals are smart materials

• having numerous applications in liquid crystal displays, modulators, sensors, solar cells, etc. Liquid crystals are used in both large and small devices. They surround us everywhere: in our house, on the street, and at our job. Liquid crystals are applied in biology and medicine, and for oil recovery as

• well as in food production. The molecules of the human body (e.g., DNA, proteins) can also form liquid crystal phases. Many applications of liquid crystals require the manipulation of structures on the nanometer scale. For example, these highly sensitive materials are capable of changing their

Photoluminescence of CdSe/ZnS quantum dots in nematic liquid crystals in electric fields

• Margarita A. Kurochkina,
• Elena A. Konshina and
• Daria Khmelevskaia

Beilstein J. Nanotechnol. 2018, 9, 1544–1549, doi:10.3762/bjnano.9.145

• obtained results are interesting for controlling the PL intensity of semiconductor QDs in liquid crystals by the application of electric fields. Keywords: aggregation; decay time; liquid crystal; luminescence intensity; orientation; Introduction Colloidal quantum dots (QDs) are a special kind of

• significantly changes their optical properties [6][7][8][9][10]. To control the properties of NPs, they are introduced into a passive or active matrix interacting with them. Liquid crystals can be an active matrix for NPs. The dielectric and optical properties of a liquid crystal (LC) vary under electromagnetic

• fields. The control of the QD luminescence in an LC matrix has both scientific and practical interest. The photoluminescence (PL) of liquid crystals doped with silver NPs, carbon nanotubes and quantum semiconductor nanoparticles were discussed in [11][12]. The control of PL of a nematic liquid crystal

Induced smectic phase in binary mixtures of twist-bend nematogens

• Anamarija Knežević,
• Irena Dokli,
• Marin Sapunar,
• Suzana Šegota,
• Ute Baumeister and
• Andreja Lesac

Beilstein J. Nanotechnol. 2018, 9, 1297–1307, doi:10.3762/bjnano.9.122

• in controlling the self-organizing processes. Keywords: binary mixture; liquid crystals; smectic phase induction; temperature-dependent FTIR; twist-bend nematogen; Introduction Nowadays liquid crystal (LC) substances possess a wide range of uses. However, it is rather rare that a single organic

• compound has the desired properties for a particular application. Since the discovery that mixtures of nematic compounds could yield room-temperature nematic liquid crystals [1], the mixing of LC compounds became a very useful technique. Thus, investigation of LC mixtures is of great interest in targeting

• spectra of liquid crystals is a consequence of disordering of chain packing and the introduction of gauche conformers on the alkyl chains which leads to their more liquid-like state [38][41][42][43]. This change is most evident at the crystal–smectic transition since in the solid state the chains are

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

• 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

• spectroscopy. Dielectric spectroscopy is a complementary technique to XRD used to characterize different phases and structures of LC phases such as twist-grain boundary SmA (TGBA) [45], antiferroelectric liquid crystals (AFLCs) [46], de Vries [47][48][49], bent-core molecular systems [50][51], etc. Here we use

A simple extension of the commonly used fitting equation for oscillatory structural forces in case of silica nanoparticle suspensions

• Sebastian Schön and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2018, 9, 1095–1107, doi:10.3762/bjnano.9.101

• observed in molecular liquids [1][2], but also in complex fluids such as liquid crystals [22][23], micellar or polyelectrolyte solutions [3][24][25][26][27][28][29] and particle suspensions [19][30][31][32][33]. Recent studies showed that for colloidal suspensions of charged silica nanoparticles the period

Optical orientation of nematic liquid crystal droplets via photoisomerization of an azodendrimer dopant

• Sergey A. Shvetsov,
• Alexander V. Emelyanenko,
• Natalia I. Boiko,
• Alexander S. Zolot'ko,
• Yan-Song Zhang,
• Jui-Hsiang Liu and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2018, 9, 870–879, doi:10.3762/bjnano.9.81

• different kinds of soft matter, such as light-driven polymers [5][6], elastomers [7][8][9] microgel particles [10][11], micelles [12][13], nematic liquid crystals (NLCs) [7][14], liquid-crystalline (LC) polymers [15][16][17][18] and Langmuir–Blodgett films [19][20] with light-controllable supramolecular

Effect of ferroelectric BaTiO₃ particles on the threshold voltage of a smectic A liquid crystal

• Abbas R. Imamaliyev,
• Mahammadali A. Ramazanov and
• Shirkhan A. Humbatov

Beilstein J. Nanotechnol. 2018, 9, 824–828, doi:10.3762/bjnano.9.76

• ferroelectric BaTiO3 particles on the planar–homeotropic transition threshold voltage in smectic A liquid crystals consisting of p-nitrophenyl p-decyloxybenzoate and 4-cyano-4′-pentylbiphenyl were studied by using capacitance–voltage (C–V) measurements. It was shown that the BaTiO3 particles significantly

• reduce the threshold voltage. The obtained result is explained by two factors: an increase of dielectric anisotropy of the liquid crystals and the formation of a strong electric field near polarized particles of BaTiO3. It was shown that the role of the second factor is dominant. The explanations of some

• features observed in the C–V characteristics are given. Keywords: colloidal systems; dielectric permittivity; ferroelectric BaTiO3 particles; smectic A liquid crystals; threshold voltage; Introduction Interest in liquid crystals (LC) as a unique state of matter arises not only from a scientific point of

High-contrast and reversible scattering switching via hybrid metal-dielectric metasurfaces

• Jonathan Ward,
• Khosro Zangeneh Kamali,
• Lei Xu,
• Guoquan Zhang,
• Andrey E. Miroshnichenko and
• Mohsen Rahmani

Beilstein J. Nanotechnol. 2018, 9, 460–467, doi:10.3762/bjnano.9.44

• for applications in modern nanophotonics, tunability of metasurfaces is required, which has become a rapidly growing area of research. These tuning capabilities have been introduced via various techniques, such as phase-change media based antennas [25][26][27], the use of liquid crystals [28][29][30

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• ) phase and then convert to a liquid. Liquid crystals are made of rod-shaped molecules that are aligned parallel to each other and show different properties in different directions (Figure 14). For example, they become transparent at high frequency and opaque at low frequency. Because of the unique

• molecular structure of the liquid crystal (LC) (i.e., that it can be simply oriented in the direction of an applied electric or magnetic field) the alignment and dispersion of the CNTs in a solution of liquid crystals is also achievable (Figure 15). The biggest advantage of this method is that small fields

• are required to align CNTs as compared to cases where liquid crystals are not used. However, difficulties in the preparation of LC phases, especially at high concentrations, limit its applications [96][97][98]. On the other hand, it is known that progress in CNT alignment using this technology depends

Dynamic behavior of nematic liquid crystal mixtures with quantum dots in electric fields

• Emil Petrescu,
• Cristina Cirtoaje and
• Octavian Danila

Beilstein J. Nanotechnol. 2018, 9, 399–406, doi:10.3762/bjnano.9.39

• on a sample containing 0.89% (mass fraction) of CdSe/ZnS quantum dots revealed a decrease of the relaxation time compared to pure 5CB. Keywords: Fréedericksz transition; nematic liquid crystals; quantum dots; Introduction The expansion of liquid crystal (LC)-based devices in common life domains as

• well as science and engineering, requires improved technologies and new materials. Materials science provides great opportunities to these technologies by synthesizing new nanoparticles that can be mixed with liquid crystals: carbon nanotubes [1][2][3], graphene, magnetic nanoparticles [4][5], gold

• nanoparticles [6], quantum dots (QDs) [7][8][9][10][11][12] or other nanomaterials [13][14][15][16][17] that can be effectively used in electro-optical devices. When added to liquid crystals, quantum dots may seriously influence their behavior under an electric field due to the anchoring forces acting on the

Temperature-tunable lasing from dye-doped chiral microdroplets encapsulated in a thin polymeric film

• Gia Petriashvili,
• Mauro Daniel Luigi Bruno,
• Maria Penelope De Santo and
• Riccardo Barberi

Beilstein J. Nanotechnol. 2018, 9, 379–383, doi:10.3762/bjnano.9.37

• 87036, Italy 10.3762/bjnano.9.37 Abstract In the last decade, much interest has grown around the possibility to use liquid-crystal droplets as optical microcavities and lasers. In particular, 3D laser emission from dye-doped cholesteric liquid crystals confined inside microdroplets paves the way for

• the field of sensors and for the development of anti-counterfeiting labels. Keywords: chiral microdroplets; dye-doped cholesteric liquid crystals; laser; polymeric films; temperature tuning; Introduction Liquid crystalline materials show peculiar optical properties. Cholesteric liquid crystals (CLCs

Periodic structures on liquid-phase smectic A, nematic and isotropic free surfaces

• Anna N. Bagdinova,
• Evgeny I. Demikhov,
• Nataliya G. Borisenko,
• Sergei M. Tolokonnikov,
• Gennadii V. Mishakov and
• Andrei V. Sharkov

Beilstein J. Nanotechnol. 2018, 9, 342–352, doi:10.3762/bjnano.9.34

• ; liquid crystals; microscopy; smectic A phase; Introduction The considerable interest in studies of liquid crystalline free boundaries that has recently arisen is due to their intrinsic free surface properties which are not influenced by the substrate anchoring [1][2]. This is very important for many

• applications, such as display quality technology and production enhancement. The free surface of liquid crystals is interesting by itself because many applications use one single boundary (e.g., coatings, paints, make-up) [3][4]. Appreciable progress in the development of tools for surface characterization

• , ISSA, SNOM, AFM. The applicability of surface-sensitive tools for liquid crystals was reviewed. We observed a periodic order of FCDs in one-dimensional chains. A periodic stripe texture is observed in SmA, nematic phases and isotropic liquid in 8CB. The periodic images of the probe depend on the

Dynamic behavior of a nematic liquid crystal with added carbon nanotubes in an electric field

• Emil Petrescu and
• Cristina Cirtoaje

Beilstein J. Nanotechnol. 2018, 9, 233–241, doi:10.3762/bjnano.9.25

• theoretical model based on elastic continuum theory was developed and the relaxation times of nematic liquid crystals with CNTs were evaluated. Experiments made with single-walled carbon nanotubes dispersed in nematic 4-cyano-4’-pentylbiphenyl (5CB) indicated a significant difference of the relaxation time

• models have to be developed for their characterization [5][6][9][10][11]. When nanoparticles are inserted in liquid crystals, nematic molecules are attached to the particle surface due to anchoring forces. Experimental studies revealed that carbon nanotubes have a strong interaction with liquid crystal

• free energy of liquid crystals with the applied electric field, is the interaction free energy between LC and SWCNTs and is the interaction free energy of the carbon nanotubes with the applied field. When a planar aligned cell is considered and the electric field is perpendicular to the support (i.e