Conductive and stretchable electrodes that can be printed directly on a stretchable substrate have drawn intensive attention for wearable electronics and electronic skins. Printable inks containing liquid metal (LM) are strong candidates for these applications, but the insulating oxide skin forming around LM particles limits their conductivity. This study reveals that hydrogen doping (H-doping) introduced by ultrasonication in the presence of aliphatic polymers makes the oxide skin highly conductive and deformable. X-ray photoelectron spectroscopy and atom probe tomography confirms hydrogen doping, and first-principles calculations are used to rationalize the obtained conductivity. Printed circuit lines show metallic conductivity (25,000 S/cm), excellent electromechanical decoupling at 500% uniaxial stretching, mechanical resistance to scratches, and long-term stability in wide ranges of temperature and humidity. The self-passivation of the printed lines allows direct printing of 3D circuit lines and double-layer planar coils that are used as stretchable inductive strain sensors.Stretchable electronic devices have received widespread attention for potential uses in healthcare monitoring 1-3 , electronic skins 4,5 , and wearable haptic devices 6,7 . One of the key technological issues in stretchable electronics is the fabrication of stretchable circuit lines, for which several characteristics are requested simultaneously; metallic conductivity, negligible resistance changes under deformations, electrical stability in harsh environments, printing of complicated circuit designs, passivation 8 , and good adhesion to elastomeric substrates 9 . Serpentine and buckled metal interconnections have achieved a few of the above requests such as metallic conductivity, small resistance changes, some degree of deformability, and environmental stability 10 . Other progress has been with conductive elastomer composites with respect to high

Cyclodextrins are capable of forming non-covalent host-guest inclusion complexation with variety of molecules in order to enhance water-solubility and thermal stability of such hydrophobic and volatile molecules. Menthol, an efficient antibacterial and flavour/fragrance agent, is used in various applications like food, pharmacy, cosmetics, however, its low water-solubility and high volatility somewhat limit its application. In this study, menthol/cyclodextrin-inclusion complex (menthol/CD-IC) was formed in highly concentrated aqueous solution by using hydroxypropyl-b-cyclodextrin (HPbCD) and hydroxypropyl-g-cyclodextrin (HPgCD). The phase solubility studies and computational modeling studies revealed that menthol and these two CDs (HPbCD and HPgCD) formed stable inclusion complexes with the optimal molar ratio of 1:1 (menthol:CD) and inclusion complex formation enhanced the watersolubility of menthol. The electrospinning of nanofibers (NFs) from highly concentrated aqueous solutions (160%, w/v) of menthol/CD-IC was successfully performed without using additional fiber forming polymer and bead-free and uniform menthol/CD-IC NFs in the form of self-standing and flexible nanofibrous webs were produced. The initial molar ratio (1:1, menthol:CD) of the menthol/CD-IC in the solutions was mostly preserved in the menthol/CD-IC NFs (above 0.70:1.00, menthol:CD). The watersolubility of menthol was enhanced and menthol/CD-IC NFs have shown fast-dissolving character. The slow-release of menthol was achieved for menthol/CD-IC NFs, and the evaporation of menthol was shifted to much higher temperature (up to 275 C) for menthol/CD-IC NFs which proved the hightemperature stability for menthol due to inclusion complexation.

The synthesis of atomically thin boron sheets on a silver substrate opened a new area in the field of two-dimensional systems. Similar to hydrogenated and halogenated graphene, the uniform coating of borophene with fluorine atoms can lead to new derivatives of borophene with novel properties. In this respect, we explore the possible structures of fluorinated borophene for varying levels of coverage (BnF) by using first-principles methods. Following the structural optimizations, phonon spectrum analysis and ab initio molecular dynamics simulations are performed to reveal the stability of the obtained structures. Our results indicate that while fully fluorinated borophene (BF) cannot be obtained, stable configurations with lower coverage levels (B4F and B2F) can be attained. Unveiling the stable structures, we explore the mechanical, electronic, and thermal properties of (BnF). Fluorination significantly alters the mechanical properties of the system, and remarkable results, including direction-dependent variation of Young’s modulus and a switch from a negative to positive Poisson’s ratio, are obtained. However, the metallic character is preserved for low coverage levels, and metal to semiconductor transition is obtained for B2F. The heat capacity at a low temperature increases with an increasing F atom amount but converges to the same limiting value at high temperatures. The enhanced stability and unique properties of fluorinated borophene make it a promising material for various high-technology applications in reduced dimensions.

The electrospinning of nanofibers (NFs) of cinnamaldehyde inclusion complexes (ICs) with two different hydroxypropylated cyclodextrins (CDs), hydroxypropyl-β-cyclodextrin (HP-β-CD) and hydroxypropyl-γ-cyclodextrin (HP-γ-CD), was successfully performed in order to produce cinnamaldehyde/CD-IC NFs without using an additional polymer matrix. The inclusion complexation between cinnamaldehyde and hydroxypropylated CDs was studied by computational molecular modeling, and the results suggested that HP-β-CD and HP-γ-CD can be inclusion complexed with cinnamaldehyde at 1:1 and 2:1 (cinnamaldehyde/CD) molar ratios. Additionally, molecular modeling and phase solubility studies showed that water solubility of cinnamaldehyde dramatically increases with cyclodextrin inclusion complex (CD-IC) formation. The HP-β-CD has shown slightly stronger binding with cinnamaldehyde when compared to HP-γ-CD for cinnamaldehyde/CD-IC. Although cinnamaldehyde is a highly volatile compound, it was effectively preserved with high loading by the cinnamaldehyde/CD-IC NFs. It was also observed that cinnamaldehyde has shown much higher temperature stability in cinnamaldehyde/CD-IC NFs compared to uncomplexed cinnamaldehyde because of the inclusion complexation state of cinnamaldehyde within the hydroxypropylated CD cavity. Moreover, cinnamaldehyde still has kept its antibacterial activity in cinnamaldehyde/CD-IC NF samples when tested against Escherichia coli. In addition, cinnamaldehyde/CD-IC NF mats were fast-dissolving in water, even though pure cinnamaldehyde has a water-insoluble nature. In brief, self-standing nanofibrous mats of electrospun cinnamaldehyde/CD-IC NFs are potentially applicable in food, oral-care, healthcare, and pharmaceutics because of their fast-dissolving character, enhanced water solubility, stability at elevated temperature, and promising antibacterial activity.

In recent years many attempts have been made to discover new types of two-dimensional (2D) nanostructures with novel properties beyond the hexagonal crystals. The prediction of pentagraphene has sparked a great deal of research interest to investigate 2D pentagonal systems. In line with these efforts, in this paper, we propose a 2D ternary pentagonal monolayer of BNSi (penta-BNSi) and systematically investigate its structural, vibrational, mechanical, piezoelectric, electronic, photocatalytic, and optical properties by performing first-principles methods. We verify the stability of the penta-BNSi monolayer from the dynamical, thermal, and mechanical aspects based on phonon dispersion, ab initio molecular dynamics, and elastic tensor analysis, respectively. The mechanical properties are examined by calculating in-plane stiffness (Y 2D ), Poisson's ratio (ν), and ultimate tensile strength and penta-BNSi is found to be soft and ductile. The electronic structure and electronic transport calculations indicate that the penta-BNSi monolayer possesses a quasidirect band gap and anisotropic, potentially high carrier mobility. Due to the noncentral symmetric character and semiconducting feature, an intrinsic piezoelectric response emerges in the structure. In addition, penta-BNSi has a suitable band gap as well as proper band edge positions for photocatalytic water splitting within practical pH levels. The analysis of optical properties, including many-body effects, points out strong exciton binding and high light absorption in the visible and near-UV parts of the spectrum. Our findings not only expand the family of 2D pentagonal materials but also uncover an ideal ultrathin material for photocatalytic applications.

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Carvacrol is a known antioxidant molecule and commonly used in food and cosmetics as a flavor and fragrance agent; however, carvacrol has major issues such as high volatility, low water solubility, and stability. In this study, carvacrol/cyclodextrin inclusion complex fibers (carvacrol/CD-IC fibers) were produced via electrospinning in order to enhance thermal stability, water solubility and shelf-life of carvacrol having antioxidant activity. The phase solubility and computational modeling studies showed that carvacrol can form inclusion complexes with two types of modified CDs, hydroxypropyl-bcyclodextrin (HPbCD) and hydroxypropyl-c-cyclodextrin (HPcCD). The carvacrol/cyclodextrin inclusion complex electrospun fibers (carvacrol/HPbCD-IC fibers and carvacrol/HPcCD-IC fibers) were obtained as free-standing fibrous webs. Although pure carvacrol is highly volatile, the electrospun carvacrol/CD-IC fibers were quite effective to preserve high amount of carvacrol due to the inclusion complexation. In addition, carvacrol/CD-IC fibers have shown higher temperature stability for carvacrol. Moreover, carvacrol/CD-IC fibers showed more effective antioxidant activity as compared to pure carvacrol. The carvacrol/CD-IC fibrous webs have shown fast-dissolving character in water due to the enhanced water solubility of carvacrol/CD-IC and their ultrafine fiber structure. In short, encapsulation of carvacrol in electrospun CD-IC fibrous webs has shown potentials for food and oral care applications due to free-standing and fast-dissolving character along with high water solubility, high temperature stability and enhanced antioxidant by carvacrol/cyclodextrin inclusion complexation.

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