Bilayers of the oxide 3d ferromagnet La0.7Sr0.3MnO3 (LSMO) and the 5d paramagnet SrIrO3 (SIO) with large spin–orbit coupling (SOC) have been investigated regarding the impact of interfacial SOC on magnetic order. For the growth sequence of LSMO on SIO, ferromagnetism is strongly altered and large out-of-plane-canted anisotropy associated with lacking magnetic saturation up to 4 T has been observed. Thin bilayer films have been grown coherently in both growth sequences on SrTiO3 (001) by pulsed laser deposition and structurally characterized by scanning transmission electron microscopy and x-ray diffraction. Measurements of magnetization and field-dependent Mn L2,3 edge x-ray magnetic circular dichroism reveal changes of the LSMO magnetic order, which are strong in LSMO on SIO and weak in LSMO underneath SIO. We attribute the impact of the growth sequence to the interfacial lattice structure, which is known to influence the interfacial magnetic coupling governed by MnO6 octahedral rotations and/or distortions.

Precise modulation of polymer brush in its thickness and grafting density can cause unexpected cell behaviors and regulated bioactivities. Herein, a nanoscale poly(dimethylsiloxane) (PDMS) brush was employed to use as a controllable material for cell adhesion. Facile fabrication of ultrathin monolayer PDMS nanobrush on an underlying substrate facilitated regaining cell adhesion through long-range cell attractive forces such as the van der Waals forces. We showed that cell adhesion is diminished by increasing the number of nanobrush layers, causing a gradual decrease of the effectiveness of the long-range force. The result demonstrates that ultrathin PDMS nanobrush can either promote or inhibit cell adhesion, which is required for various biomedical fields such as tissue-engineering, anti-fouling coating, and implantable biomaterials and sensors.

Russian Foundation of Basic Research;Russian Academy of Sciences;Eur. Off. Aerospace R and D of the US AirForce;Society for Information Display;Russian JSC ChipExpo

Optoelectrical manipulation has recently gained attention for cellular engineering; however, few material platforms can be used to efficiently regulate stem cell behaviors via optoelectrical stimulation. In this study, we developed nanoweb substrates composed of photoactive polymer poly(3-hexylthiophene) (P3HT) to enhance the neurogenesis of human fetal neural stem cells (hfNSCs) through photo-induced electrical stimulation.METHODS:The photoactive nanoweb substrates were fabricated by self-assembled one-dimensional (1D) P3HT nanostructures (nanofibrils and nanorods). The hfNSCs cultured on the P3HT nanoweb substrates were optically stimulated with a green light (539 nm) and then differentiation of hfNSCs on the substrates with light stimulation was examined. The utility of the nanoweb substrates for optogenetic application was tested with photo-responsive hfNSCs engineered by polymer nanoparticle-mediated transfection of an engineered chimeric opsin variant (C1V1)-encoding gene.RESULTS:The nanoweb substrates provided not only topographical stimulation for activating focal adhesion signaling of hfNSCs, but also generated optoelectrical stimulation via photochemical and charge-transfer reactions upon exposure to 539 nm wavelength light, leading to significantly enhanced neuronal differentiation of hfNSCs. The optoelectrically stimulated hfNSCs exhibited mature neuronal phenotypes with highly extended neurite formation and functional neuron-like electrophysiological features of sodium currents and action potentials. Optoelectrical stimulation with 539 nm light simultaneously activated both C1V1-modified hfNSCs and nanoweb substrates, which upregulated the expression and activation of voltage-gated ion channels in hfNSCs and further increased the effect of photoactive substrates on neuronal differentiation of hfNSCs.CONCLUSION:The photoactive nanoweb substrates developed in this study may serve as platforms for producing stem cell therapeutics with enhanced neurogenesis and neuromodulation via optoelectrical control of stem cells.

Current treatments for wound healing engage in passive healing processes and rarely participate in stimulating skin cell behaviors for active wound healing. Electric potential difference‐derived electrical fields (EFs) are known to modulate skin cell behaviors. Here, a piezoelectric dermal patch is developed that can be applied on skin wound site and EF is generated to promote wound healing. The one‐directionally aligned zinc oxide nanorod‐based piezoelectric patch generates piezoelectric potential upon mechanical deformations induced by animal motion, and induces EF at the wound bed. In vitro and in vivo data demonstrate that the piezoelectric patch promotes the wound healing process through enhanced cellular metabolism, migration, and protein synthesis. This modality may lead to a clinically relevant piezoelectric dermal patch therapy for active wound healing.

The diagonal viewing angle light leakage in a black state of in-plane switching (IPS) liquid crystal display (LCD) associated with pretilt angle has been investigated. The mechanical rubbing process with a cloth causes relatively high pretilt angle in the homogenously aligned liquid crystals (LCs) so that the tilted LC director results in increase of a light leakage in a black state at diagonal viewing angles. In this study, we theoretically estimated using classical optic theory how the light leakage in a black state at diagonal viewing angle is associated with the pretilt angle and also proposed an effective method to reduce the pretilt angle from 1.5 degrees to 0 degrees in rubbed IPS LCD by utilising polymer stabilisation. With this approach, we could successfully acquire a better black quality in all viewing angles as compared with normal IPS LCD.[GRAPHICS].

We fabricated a solution-processed laminated dielectric and investigated its structural, optical, and electrical properties. The laminated ZrO2 (Z) and Al2O3 (A) dielectric effectively blocked the leakage current density (J leak) and showed a high breakdown voltage. In particular, the AZA laminated dielectric showed a lower J leak and a higher breakdown voltage than the ZAZ dielectric, because of the large band gap and minimal defects in the Al2O3 film. Finally, we demonstrated the low-voltage indium zinc oxide thin-film transistor (less than 3 V) on laminated dielectric, which displayed excellent switching characteristics.

A wearable thermoelectric generator, woven on a wristband, consisting of chemically exfoliated n- and p-type transition metal dichalcogenide nanosheets.

High-performance, solution-processed transparent and flexible zinc oxide (ZnO) nanorods (NRs)-based single layer network structured (SLNS) thin film transistors (TFTs) were developed on polyethylene terephthalate (PET) substrate at 100 °C. Keeping the process-temperature under 100 °C, we have improved the device performance by introducing three low temperature-based techniques; re-growing ZnO to fill the void spaces in a single layer network of ZnO NRs, passivating the back channel with polymer, and adopting ZrO2 as the high-k dielectric. Notably, high-k amorphous ZrO2 was synthesized and deposited using a novel method at an unprecedented temperature of 100 °C. Using these methods, the TFTs exhibited a high mobility of 1.77 cm(2)/V·s. An insignificant reduction of 2.18% in mobility value after 3000 cycles of dynamic bending at a radius of curvature of 20 mm indicated the robust mechanical nature of the flexible ZnO NRs SLNS TFTs.

The light leakage in a black state of in-plane switching (IPS) liquid crystal display (LCD) associated with rubbing process has been investigated. The mechanical rubbing process with a cloth caused orientation disorders in the liquid crystal directors and these partial orientation disorders result in residual retardations of the IPS LCD, causing the light leakages at the black state. In this study, we theoretically estimated how the light leakage is associated with the rubbing uniformity using 2 x 2 Jones matrix equation and also experimentally confirmed how it is associated with structural properties of the alignment layer. The light leakage was clearly reduced in the alignment layer with reduced crystallinity and flexibility.[GRAPHICS]

Soluble polyimide-type alignment layer is widely used in in-plane switching (IPS) liquid crystal display (LCD) because of its excellent reliability owing to high imidisation ratio during long-term driving, high voltage-holding ratio and low ion density. Nevertheless, it exhibits slow direct current (DC) discharging property due to its high resistivity, causing significant DC image-sticking problem. In this study, we doped inorganic salt to control the resistivity of soluble polyimide-type alignment layer and found that this approach reduced DC image sticking greatly without any loss of reliability property in IPS-LCD.[GRAPHICS].

We introduce a microscale soft pattering (MSP) route utilizing contact printing of chemically inert sub-nanometer thick low molecular weight (LMW) poly(dimethylsiloxane) (PDMS) layers. These PDMS layers serve as a release agent layer between the n-type Ohmic metal and metal oxide semiconductors (MOSs) and provide a layer that protects the MOS from water in the surrounding environment. The feasibility of our MSP route was experimentally demonstrated by fabricating solution processable In2O3, IZO, and IGZO TFTs with aluminum (Al), a typical n-type Ohmic metal. We have demonstrated patterning gaps as small as 13 μm. The TFTs fabricated using MSP showed higher field-effect-mobility and lower hysteresis in comparison with those made using conventional photolithography.

An energy harvesting system using a triboelectric generator (TEG), which converts a small amount of mechanical energy to available electrical energy, has recently been developed by combining a simple one-directional mechanical force (contact and separation or sliding back and forth) with a 2D device materials. However, with regard to using the TEG in real world applications, there is no TEG design suitable for utilizing a variety of mechanical forces and for generating triboelectric charge in various environmental conditions, especially under high relative humidity. In this work, we introduce a design for a humidity-independent triboelectric generator (HITEG) that can generate triboelectric charges with a granular system by simple rotating or shaking under high relative humidity conditions. The HITEG can generate an open-circuit voltage of 81.63 V and a short-circuit current of 213.9 nA using 80 polytetrafluoroethylene beads.

The ultrathin low-molecular-weight (LMW) polydimethylsiloxane (PDMS) layer clearly provides chemical extreme wettability without any change of physical parameters. Contact printing of a PDMS stamp can easily achieve a layer, which induces numerous hydroxyl groups via photochemical oxidation. The layer-induced extreme wettability exhibits a superior antifogging performance on spectacle lenses without any effects on the optical prescription. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for online delivery, but are not copy-edited or typeset. Technical support issues arising from supporting information (other than missing files) should be addressed to the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

A simple strategy for changing a brittle conducting polymer (PEDOT:PSS) into a solution-processed highly deformable viscoelastic polymer is presented by H.-K. Baik, U. Jeong, and co-workers on page 4455. The storage modulus versus loss modulus of the polymer is adjusted to control the viscoelastic properties to fit the properties required in deformable electronics. Rapid self-healing of conductivity, custom-designed LEDs with complex micropatterns, and foldable stretchable LEDs are demonstrated.

In this paper, solution-based deposition of HfO 2 thin film at low temperature was demonstrated. By using aqueous HfCl 4 solution, the precursor was effectively decomposed with low annealing temperature of 150 °C. Thus it is preferable to use this solution for dielectric coating on flexible substrates. To achieve conformal coating on substrate, formic acid as a cosolvent was added to aqueous ink solution to reduce surface tension of the solution. Due to improved coating quality of HfO 2 thin film, the fabricated HfO 2 gate dielectric shows reliable breakdown characteristics and low leakage current.

We introduce an easy process for the fabrication of solution-processed indium oxide (InO) thin film transistors (TFTs) by heating a precursor solution. InO TFTs fabricated from solutions of an InO precursor heated at 90 °C had the highest mobility of 4.61 cm 2 V −1 s −1 after being annealed at 200 °C. When the InO precursor solution is heated, HNO 3 may be thermally evaporated in the InO precursor solution. Nitrogen atoms can disrupt hydrolysis and condensation reactions. An InO thin film deposited from a solution of the heated InO precursor is advantageous for hydrolysis and condensation reactions due to the absence of nitrogen atoms.

We examined solution-processed alkaline-earth-metal doped gallium indium oxide (GIO) thin film transistors (TFT) and studied the relationship between the dopant species and the threshold voltage (V-th) stability. As the atomic number of the dopant increases, the amount of oxygen vacancies, which act as the major defect sites, decreased and the V-th stability is enhanced. The electron trapping times and total defect sites were quantitatively calculated. Particularly, Sr-doped GIO TFT show the highest V-th stability under positive gate bias and the origin of V-th stability enhancement is deduced by using the partial charge model and reaction kinetics.

Enhanced hydration lowers the dehydroxylation temperature of the sol–gel inks, resulting in high-performance metal oxide thin film transistors.