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Our experimental outturn opens up a new vision by proposing mechano-responsive charge transfer mechanism (MRCTM) to π-conjugated polymers in the field of human-motion interactive energy harvester. Doped polyaniline (d -PANi) has been used to functionalize conducting textile fibers (f -CTFs) and integrated with our proposed design for wearable power plant. Each f -CTF generates current by patting, bending, or even soft touching. Localized force deformation at the metal/polymeric interface layer with direct visualization of charge distribution pattern has been extensively studied by atomic force microscopy. The integrated arrays of f -CTFs produce a peak power-density of ∼0.6 W m−2 with output current-density of ∼22 mA m−2 and can power at least 10 white LEDs of 2.5 W. The procured energy from f -CTFs is capable of charging a commercial 10 μF capacitor to 3 V in 80 s and powering portable electronic devices. The prototype energy harvester stably shows the same performance after more than 100 thousand times of patting, bending or twisting. Prototyped wearable power plant; integrated from doped polyaniline (d -PANi) functionalized free standing textile fibers, harvesting energy through body movement like patting, bending, or even through soft finger touch. Image 1 • Polyaniline as a conjugated polymer is used for mechano-responsive energy harvesting to power portable electronic devices. • Each free-standing textile fiber functionalized by d -PANi generates current by patting, bending, or even soft touching. • Our prototyped device is working stably after more than 100 thousand times of patting, bending or twisting. • Our proposed research approach and manufacturing product concept address both technical performance and cost-effectiveness. [ABSTRACT FROM AUTHOR]

Streptococcus dysgalactiae subsp. dysgalactiae (SDSD), a Lancefield group C streptococci (GCS), is a frequent cause of bovine mastitis. This highly prevalent disease is the costliest in dairy industry. Adherence and biofilm production are important factors in streptoccocal pathogenesis. We have previously described the adhesion and internalization of SDSD isolates in human cells and now we describe the biofilm production capability of this bacterium. In this work we integrated microbiology, imaging and computational methods to evaluate the biofilm production capability of SDSD isolates; to assess the presence of biofilm regulatory protein BrpA homolog in the biofilm producers; and to predict a structural model of BrpA-like protein and its binding to putative inhibitors. Our results show that SDSD isolates form biofilms on abiotic surface such as glass (hydrophilic) and polystyrene (hydrophobic), with the strongest biofilm formation observed in glass. This ability was mainly associated with a proteinaceous extracellular matrix, confirmed by the dispersion of the biofilms after proteinase K and trypsin treatment. The biofilm formation in SDSD isolates was also confirmed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Under SEM observation, VSD16 isolate formed cell aggregates during biofilm growth while VSD9 and VSD10 formed smooth and filmy layers. We show that brpA -like gene is present and expressed in SDSD biofilm-producing isolates and its expression levels correlated with the biofilm production capability, being more expressed in the late exponential phase of planktonic growth compared to biofilm growth. Fisetin, a known biofilm inhibitor and a putative BrpA binding molecule, dramatically inhibited biofilm formation by the SDSD isolates but did not affect planktonic growth, at the tested concentrations. Homology modeling was used to predict the 3D structure of BrpA-like protein. Using high throughput virtual screening and molecular docking, we selected five ligand molecules with strong binding affinity to the hydrophobic cleft of the protein, making them potential inhibitor candidates of the SDSD BrpA-like protein. These results warrant further investigations for developing novel strategies for SDSD anti-biofilm therapy. [ABSTRACT FROM AUTHOR]

Abstract Optical solutions are promising for Perovskite solar cell (PSC) technology, not only to increase efficiency, but also to allow thinner absorber layers (higher flexibility) and improve stability. This work optimized the combined anti-reflection and scattering properties of two types of light trapping (LT) structures, based on TiO 2 semi-spheroidal geometries with honeycomb periodicity, for application in PSCs with substrate configuration and different perovskite layer thicknesses. Their optically lossless material (TiO 2) allows the structures to be patterned in the final processing steps, integrated in the cells' top n contact, therefore not increasing the surface area of the PV layers and not degrading the electric performance via recombination. Therefore, this strategy circumvents the typical compromise of state-of-the-art LT approaches between optical improvements and electrical deterioration, which is particularly relevant for PSCs since their main recombination is caused by surface defects. When patterned on the cells' front, the wave-optical micro-features composing the LT structures yield up to 21% and 27% photocurrent enhancement in PSCs with conventional (500 nm thick) and ultra-thin (250 nm) perovskite layers, respectively; which are improvements close to those predicted by theoretical Lambertian limits. In addition, such features are shown to provide an important encapsulation role, preventing the cells' degradation from UV penetration. Graphical abstract fx1 Highlights • Novel light trapping designs optimized for high-efficient Perovskite solar cells. • Wave-optical front structures provide strong VIS anti-reflection & NIR scattering. • Incorporation in n contact prevents electric degradation while boosting absorption. • Record photocurrent enhancement (35%) demonstrated in thin (250 nm) Perovskite cell. • Photonic structures act as UV blocking layer, enhancing Perovskite cell stability. [ABSTRACT FROM AUTHOR]

The interaction of light with wavelength-sized photonic nanostructures is highly promising for light management applied to thin-film photovoltaics. Several light trapping effects come into play in the wave optics regime of such structures that crucially depend on the parameters of the photonic and absorbing elements. Thus, multi-parameter optimizations employing exact numerical models, as performed in this work, are essential to determine the maximum photocurrent enhancement that can be produced in solar cells. Generalized spheroidal geometries and high-index dielectric materials are considered here to model the design of the optical elements providing broadband absorption enhancement in planar silicon solar cells. The physical mechanisms responsible for such enhancement are schematized in a spectral diagram, providing a deeper understanding of the advantageous characteristics of the optimized geometries. The best structures, composed of TiO 2 half-spheroids patterned on the cells' top surface, yield two times higher photocurrent (up to 32.5 mA/cm 2 in 1.5 µm thick silicon layer) than the same devices without photonic schemes. These results set the state-of-the-art closer to the theoretical Lambertian limit. In addition, the considered light trapping designs are not affected by the traditional compromise between absorption enhancement versus current degradation by recombination, which is a key technological advantage. [ABSTRACT FROM AUTHOR]

Self-powered devices are the need of the hour for future technologies and next-generation electronics that require both smartness and sustainability. Here, we have presented an ultra-thin (~ 0.18 mm) self-powered paper-based prototype as a touch-interactive electronic tag for next-generation Internet of Things (IoT) enabling smart security applications. A touch-interactive power paper (TiPP) was developed using in-situ polymerization followed by painting an electrode layer of graphite/silver onto it. Thus, a simple piece of paper was used for energy harvesting without having any physical separation from the electrode of the system. It instantaneously generated an electrical signal of 0.91 W m−2 due to a mechano-responsive charge transfer mechanism. Apart from using conventional electrode materials, graphite pencils were also utilized towards a more simple, environmentally friendly and cost-effective approach. Further, different arrays of TiPP have been designed to create a unique coding system (high/low signal) that can simultaneously enable self-powered sensing and an identification system. This is exhibited by a rapid but simple signal processing method used in several applications like R-G-B color codes, personal ID cards and product identification tags. A straightforward signal processing circuit that includes an effective simulation, is demonstrated to validate the working principle of such self-powered security identification tags. [Display omitted] • Polypyrrole functionalized paper used as active mechanical energy harvester. • Working electrode without physical separation gives a thin device structure. • Prototyped Security tags are interfaced with wireless communication system. • Working principle of electronic logics in the system detailed with simulation. • Prototypes are designed with green and low-cost materials. [ABSTRACT FROM AUTHOR]

A new method for depositing PDMS directly onto conductive carbon yarns is proposed to produce Triboelectric Nanogenerator Yarns (TENG yarns) that can serve as the basic building blocks for energy scavenging wearables. The in-situ PDMS curing method described in this study allows the fast formation of a uniform thick coating over conductive surfaces regardless of their roughness. Single-electrode configuration TENG yarns are developed and their electrical output is optimized by precisely adjusting the PDMS layer thickness and by changing the chemical and physical nature of the carbon fiber (CF) yarns' surface. Functionalizing the CF yarns' surface with ZnO rods combined with porous PDMS coating can enhance their electrical output. The best results are achieved using this type of TENG yarns with an average diameter of 1.74 mm, which can be obtained after only 3 min of PMDS deposition by " in-situ " curing method. A maximum of 72 V peak-to-peak and 10 µA (74.1 µW cm−2 of power density with a load resistance of 20 MΩ) is reached when applying an impact force of 600 N to a set of five TENG yarns connected in parallel. The output is stable even after 10,000 cycles and this set of TENG yarns is also able to light at least 28 LEDs when tapping by hand, proving a contribute towards the development of basic building blocks to power the future generation of wearables. R. Barras and co-workers explore a new technique for the production of TENG yarns. This new deposition method features the fast formation of uniform thick and porous coatings of PDMS over conductive carbon fiber surfaces by in-situ curing using joule effect. A maximum power density of 74.1 µW cm−2 was obtained when ZnO nanorods are coating the carbon fiber core [Display omitted] • Radically new method to cure porous PDMS around fiber structures using localized Joule heating. • Precise control over thickness and porosity of the conformable PDMS coating over carbon fiber coated with ZnO rods. • High power triboelectric nanogenerators were achieved by controlling the thickness uniformity and porosity of the PDMS. • Mechanism for contact electrification proposed for the developed nanogenerators. • Weavable fiber based nanogenerators and its integration in proof-of-concept textiles. [ABSTRACT FROM AUTHOR]

In this paper, we present the preliminary results concerning the deposition of highly transparent and conductive gallium-doped zinc oxide (GZO) deposited on transparent flexible substrate based on cellulose derivatives. Prior to the deposition of the GZO film, the surface of the polymer have been coated with a thin silicon dioxide (SiO2) layer deposited by thermal evaporation assisted by an electron gun. By doing this surface treatment, we succeeded in depositing highly conductive and transparent GZO with an electrical resistivity of 2.0×10−3 Ω cm and an average optical transmittance in the visible part of the spectrum (400–700 nm) of 70% by r.f. magnetron sputtering at room temperature. Besides the optoelectronic properties, the films are mechanically stable with a polycrystalline structure with a strong preferred (002) orientation, parallel to the substrate. [Copyright &y& Elsevier]

In this paper, we present results concerning the thickness dependence (from 70 to 890 nm) of electrical, structural, morphological and optical properties presented by gallium-doped zinc oxide (GZO) deposited on polyethylene naphthalate (PEN) substrates by r.f. magnetron sputtering at room temperature. For thicknesses higher than 300 nm an independent correlation between the electrical, morphological, structural and optical properties are observed. The lowest resistivity obtained was 5×10−4 Ω cm with a sheet resistance of 15 Ω/□ and an average optical transmittance in the visible part of the spectra of 80%. It is also shown that by passivating the surface of the polymer by depositing a thin silicon dioxide layer the electrical and structural properties of the films are improved nearly by a factor of two. [Copyright &y& Elsevier]

Gallium-doped zinc oxide films were prepared by r.f. magnetron sputtering at room temperature as a function of the substrate–target distance. The best results were obtained for a distance of 10 cm, where a resistivity as low as 2.7×10−4 Ω cm, a Hall mobility of 18 cm2/Vs and a carrier concentration of 1.3×1021 cm−3 were achieved. The films are polycrystalline presenting a strong crystallographic c-axis orientation (002) perpendicular to the substrate. The films present an overall transmittance in the visible part of the spectra of approximately 85%, on average. [Copyright &y& Elsevier]