A new nanostructured α-Fe2O3 photoelectrode synthesized through plasma-enhanced chemical vapor deposition (PE-CVD) is presented. The α-Fe2O3 films consist of nanoplatelets with (001) crystallographic planes strongly oriented perpendicular to the conductive glass surface. This hematite morphology was never obtained before and is strictly linked to the method being used for its production. Structural, electronic, and photocurrent measurements are employed to disclose the nanoscale features of the photoanodes and their relationships with the generated photocurrent. α-Fe2O3 films have a hierarchical morphology consisting of nanobranches (width ∼10 nm, length ∼50 nm) that self-organize in plume-like nanoplatelets (350-700 nm in length). The amount of precursor used in the PE-CVD process mainly affects the nanoplatelets dimension, the platelets density, the roughness, and the photoelectrochemical (PEC) activity. The highest photocurrent (j = 1.39 mA/cm(2) at 1.55 VRHE) is shown by the photoanodes with the best balance between the platelets density and roughness. The so obtained hematite hierarchical morphology assures good photocurrent performance and appears to be an ideal platform for the construction of customized multilayer architecture for PEC water splitting.

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Magnetite nanoparticles of 5 nm mean diameter, coated with 10-undecynoic acid, have been anchored to crystalline Si(100) surfaces via the hydrosilylation reaction at 180 °C. The iron content in the sample (0.54 ± 0.05 μg/cm2) has been determined by atomic absorption analysis. The sample has been further characterized by X-ray photoelectron spectroscopy, field emission scanning, scanning-tunneling, and atomic force (AFM) microscopies. The thermal anchoring does not alter the morphology of the nanoparticles, causing only a slight oxidation of their surfaces. However, a second layer of nanoparticles was also formed, covering about 50% of the surface. The magnetic properties were studied using a SQUID magnetometer. ZFC (zero-field cooled) and FC (field cooled) curves were obtained in the 5−300 K temperature range. The ZFC curve shows a rounded maximum at T max ∼20 K. A hysteretic magnetization cycle was also observed at 5 K with associated magnetization saturation and coercitivity values of 40 emu/g and 160 Oe, respectively. The magnetic behavior of the sample was found to be typical of an assembly of noninteracting (or very weakly interacting) super-paramagnetic particles.

Electroluminescent polymeric nanofibers embedding dye‐loaded zeolite L crystals are prepared. By exciting the polymer nanofiber, the energy is transferred to the fluorescent dyes inside the zeolite L channels through a two‐step Förster resonant energy transfer process. This study opens new perspectives in the field of low‐cost fabrication technology of flexible nanoscale OLEDs.