Marian Lehocky

Chemical bath deposition of cerium doped BiVO4

Abstract The preparation of Ce doped BiVO 4 coatings on glass, by the thermal treatment of aqueous solutions containing a bismuth (III) ethylenediaminetetra-acetate chelate, vanadium (V) and cerium (III) species, is described here. The influence of cerium content on the colour properties of the coating was investigated. The coatings consist on morphological well-defined particles forming dense monolayers.

Application of extremely non-equilibrium plasmas in the processing of nano and biomedical materials

Some applications of extremely non-equilibrium oxygen plasma for tailoring the surface properties of organic as well as inorganic materials are presented. Plasma of low or moderate ionization fraction and very high dissociation fraction is created by high frequency electrodeless discharges created in chambers made from a material of low recombination coefficient. The O atom density often exceeds 1021 m−3 which allows for rapid functionalization of carbon-containing materials. Surface saturation with polar oxygen-rich groups is achieved in a fraction of a second and further exposure leads to etching. The etching is often non-uniform and results in nano-structuring of surface morphology. A combination of rich morphology and saturation with polar functional groups allows for a super-hydrophilic character of originally hydrophobic materials. Polymer composites are etched selectively so the polymer component is removed from the sample surface, leading to modified surface properties. Furthermore, such a treatment allows for distinguishing the distribution and orientation of fillers inside the polymer matrix. The exposure of inorganic materials to non-equilibrium oxygen plasma causes one-dimensional growth of metal oxide nanoparticles, thus representing a unique technique for the rapid catalyser-free growth of nanowires.

Significant Characteristics of Medical-Grade Polymer Sheets and their Efficiency in Protecting Hydrogel Wound Dressings: A Soft Polymeric Biomaterial

Hydrogel dressings are soft biomaterials that need protection from external influences. Polymer sheets such as breathable film (BF) or breathable laminate (BL) were characterized in respect of water vapor transmission, water contact angle, microbial penetrability, and antimicrobial property to protect hydrogel dressings. The mechanical property and water retention ability of hydogels PVP-CMC and PVP-CMC-BA with and without BF and BL have been examined. Hydrogels covered with either BF or BL show better mechanical flexibility; however, their water retention capacity increases reasonably. The determined efficient properties of polymer sheets established that BF is better than BL as a protective sheet cover for hydrogel dressings.