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In this paper the fabrication of highly porous 1D nanostructures by a vacuum and plasma etching combined protocol is presented. Zn-phthalocyanine (ZnPc) is utilized as a solid precursor to form the ZnO. First the ZnPc is sublimated in low argon pressure. Depending on the substrate temperature and microstructure, polycrystalline films or single crystal ZnPc nanowires are grown. These starting materials are then subjected to a remote plasma oxidizing treatment. Experimental parameters such as substrate position, plasma power, treatment duration, and substrate temperature determine the microstructure and properties of the final ZnO nanostructures. The article gathers an in depth study of the obtained porous nanostructured films following scanning and transmission electron microscopy (SEM and TEM), X-ray photoelectron spectroscopy (XPS), X-ray Diffraction (XRD), UV-Vis transmittance, and fluorescence spectroscopies. [ABSTRACT FROM AUTHOR]

A family of 1D organic/inorganic core/shell materials formed by an inner organic nanowire (ONW) conformally covered with an inorganic wide band gap semiconductor (ZnO or TiO2) layer is presented. The developed procedure is a two-steps vacuum methodology involving the formation of supported single crystal small-molecule nanowires by physical vapor deposition and plasma enhance chemical vapor deposition (PECVD) of the inorganic shell. Critical characteristics of the last technique are the possibilities of low temperature and remote configuration deposition. Additionally, an initial step has to be included in order to create nucleation centers for the growth of the ONWs. The procedure and its general character in terms of the variability in organic core and inorganic shells composition and the applicability of the technique to different substrates are presented. The formation of the inorganic shell with no damage of the organic core single-crystalline structure is demonstrated by high resolution transmission electron microscopy. The vertical alignment of the hybrid nanostructure is achieved thanks to the interaction of the 1D organic nanostructured surfaces and the glow discharge during the deposition of the inorganic shell by PECVD. The optical properties of these core/shell NWs are studied by fluorescence spectroscopy and microscopy, and their application as nanoscale waveguides in the 550-750 nm range addressed. [ABSTRACT FROM AUTHOR]

This work reports the low temperature plasma formation of Ag@TiO2 nanorods (NRs) on processable substrates. The layers have been analyzed by electron microscopy and secondary ion mass spectroscopy. The NRs morphologies suggest that the plasma sheath, the high mobility of the silver and the incoming direction of the precursor moieties are key factors determining their shape, dimensions, and tilting orientation. Both amorphous and anatase Ag@TiO2 NRs surfaces are superhydrophobic, and turn into superhydrophilic by irradiation with UV light. This wetting behavior is discussed by considering the water penetration in the inter-NR space during the light-mediated transformation. [ABSTRACT FROM AUTHOR]

This article aims toward a full description of the wettingconversionfrom superhydrophobicity to superhydrophilicity under illuminationwith UV light of high-density ZnO nanorods surfaces by (i) followingthe evolution of the clusters and superstructures formed by the nanocarpeteffect as a function of the water contact angle (WCA); (ii) characterizationof the superhydrophobic and superhydrophilic states with an environmentalscanning electron microscope (ESEM); and (iii) using the nanocarpeteffect as a footprint of both local and apparent water contact angles.Thus, the main objective of the article is to provide a general visionof the wettability of 1D photoactive surfaces. In parallel, the nanocarpet(NC) formation by clustering of vertically aligned ZnO nanorods (NR)when water is dripped on their surface and then dried is studied forthe first time by taking advantage of the possibility of tuning thesurface water contact angle of the ZnO NR structure under UV preillumination.As a result, we demonstrate the feasibility of controlling the sizeand other morphological characteristics of the NCs. Moreover, a stronganisotropic wetting behavior, characterized by a Δθ =θ∥ – θ⊥= 30°, is shown on an asymmetrically aligned NC surface resultingfrom arrays of tilted NRs. The study of the condensation/evaporationof water on/from an as-prepared (superhydrophobic) or a preilluminated(superhydrophilic) NR surface examined by an environmental scanningelectron microscope has evidenced the formation of supported waterdroplets with polygonal shapes in the first case and the completefilling of the inter-NR space in the latter. The long-term stabilityof the NC clusters has been utilized as a footprint to track the penetrationdepth of water within the inter-NR space in the three borderline regionsof water droplets. This analysis has shown that for moderately hydrophobicsurfaces (i.e., water contact angles lower than 130°) water dropletsdo not present a well-defined borderline trace but a spreading regionwhere water penetrates differently with the NR interspace. The transitionfrom a Cassie–Baxter to a modified Cassie–Baxter tofinish in a Wenzel wetting state is found on these surfaces dependingon the UV preillumination time and is explained with a model wherewater interaction with the NR units is the critical factor determiningthe macroscopic wetting behavior of these surfaces. [ABSTRACT FROM AUTHOR]

A facile method to synthesize a TiO2/PEDOT:PSS hybrid nanocomposite material in aqueous solution through direct current (DC) plasma processing at atmospheric pressure and room temperature has been demonstrated. The dispersion of the TiO2 nanoparticles is enhanced and TiO2/polymer hybrid nanoparticles with a distinct core shell structure have been obtained. Increased electrical conductivity was observed for the plasma treated TiO2/PEDOT:PSS nanocomposite. The improvement in nanocomposite properties is due to the enhanced dispersion and stability in liquid polymer of microplasma treated TiO2 nanoparticles. Both plasma induced surface charge and nanoparticle surface termination with specific plasma chemical species are proposed to provide an enhanced barrier to nanoparticle agglomeration and promote nanoparticle-polymer binding. [ABSTRACT FROM AUTHOR]

Single‐crystal organic nanowires are fabricated and covered by an inorganic wide‐bandgap semiconducting shell via chemical vapor deposition. The wires are vertically aligned by A. Borras and co‐workers and supported on processable substrates. This method is widely applicable to a range of materials. The waveguide effect on the fluorescence emission of the organic cores and their application as nanoscale waveguides in the 550–750 nm range are explored on page 5981 using perylene and ZnO. [ABSTRACT FROM AUTHOR]