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This work reports flexible fully transparent high-voltage diodes that feature high rectification ratio ( R r ~ 10 8 ) and high breakdown voltage ( V b ~ 150 V) simultaneously, combined with their applications as building blocks of energy management systems in wearable electronics where triboelectric nanogenerators (TENGs) are used as power source. Both experimental results and technology computer aided design (TCAD) simulations suggest that R r and V b can be modulated by the offset length in an opposite tendency. The low reverse leakage current (~ 10 –15 A/μm) guarantees an ultra-low power consumption in standby mode, which is a core issue in wearable device applications. Besides the unprecedented electrical performance, the diodes exhibit good mechanical robustness with minimal degradation throughout the strain and fatigue tests. By incorporating these high-voltage diodes into half-wave and full-wave rectifier circuits, the high alternating current (AC) output voltage of TENGs is successfully rectified into direct current (DC) voltage and charged into supercapacitors (SCs), indicating their high integration and compatibility with TENGs, and thus their promising applications in various wearable electronic systems. [ABSTRACT FROM AUTHOR]

In the work described on this paper, the inhibitory effect of 10 flavonoids on pepsin and the interactions between them were investigated by a combination of spectroscopic and molecular docking methods. The results indicated that all flavonoids could bind with pepsin to form flavonoid–pepsin complexes. The binding parameters obtained from the data at different temperatures revealed that flavonoids could spontaneously interact with pepsin mainly through electrostatic forces and hydrophobic interactions with one binding site. According to synchronous and three-dimensional fluorescence spectra and molecular docking results, all flavonoids bound directly into the enzyme cavity site and the binding influenced the microenvironment and conformation of the pepsin activity site which resulted in the reduced enzyme activity. The present study provides direct evidence at a molecular level to understand the mechanism of digestion caused by flavonoids. [ABSTRACT FROM AUTHOR]

We report a high-responsivity ultraviolet photodetector fabricated from fluorine doped Mg 0.4 Zn 0.6 O thin film grown by molecular beam expitaxy. The doped epitaxial film demonstrates a low resistivity with a carrier concentration of 2.18 × 10 17 cm − 3 and mobility of 2.67 cm 2 /V s − 1 by Van der Pauw Hall measurements. With a further study of a single Ti/Au-MgZnO:F Schottky junction, it is found the device has a lowered barrier height of 0.59–0.64 eV compared with the calculated value. Our photodetector configured with a metal-semiconductor-metal structure with Ti/Au interdigital electrodes exhibits a high photoresonsivity of 80 A/W, nearly 800 times larger than that of undoped sample. This record-high value is attributed to the lowered Schottky barrier as well as reduced barrier thickness thanks to the effective fluorine doping. [ABSTRACT FROM AUTHOR]

Abstract: A new kind of metal-organic hybrid materials composed of the nickel ions and poly(p-phenylenediamine) have been synthesized in aqueous solution. Long hybrid rods and large nanosheets have been obtained by using the different ratios of the initial reactants. The synthesized rods and nanosheets have been characterized by SEM, TEM, AFM and XPS. The synthesized rods have been found to have porous polymeric structures. The nanosheets are made up of many small nanoparticles. [Copyright &y& Elsevier]

Flexible transparent ZnO thin-film transistors (TFTs) have gained momentum during the last decade because of the increasingly emerging demands in flexible transparent displays and wearable electronics industry. However, the instability issue regarding a deviation of turn-on voltage under gate bias stress has remained unsettled, greatly impeding the progress towards practical applications. Here we present a solution to this problem by adopting a new dual-source device architecture to self-diagnose and pull back the deviated turn-on voltage. The dual-source TFTs were fabricated on PEN substrate by conventional UV photolithography with ZnO channel prepared by magnetron sputtering technique. By combining the presented device architecture with a rapid correction process, the turn-on voltage shift was reduced to 0.1 V under −15 V gate voltage bias stress of 5000 s, which favors low power consumption circuits by preventing the TFTs drifting from enhancement to depletion mode. To illustrate its unique working mechanism, device physics simulation, square-law model deduction and circuit current analysis were carried out. The methodology we developed enhances the stability of flexible transparent oxide TFTs and can be adapted in other microelectronic and optoelectronic devices. • Flexible fully transparent thin-film transistors are fabricated. • Novel dual-source transistor structure is presented. • The gate bias instability problem can be readily solved. • TCAD device simulation is conducted to study the working principle. [ABSTRACT FROM AUTHOR]