The article presents the results of studies on the efficacy of water desalination (i.e. Elimination of NaCl ions from the solution) using graphene-polyamide composite membranes. The membrane used for filtration consists of a monolayer of polycrystalline graphene on a porous polyamide carrier support (nylon 66). The degree of desalination for an aqueous NaCl solution percolated through the membrane was 18%. In the future this type of membrane may replace the currently used reverse osmosis membranes.
This article presents the research results on impact of the method of polycrystalline graphene layers separation from the growth substrate on the obtained carbon material quality. The studies were carried out on graphene sheets obtained by metallurgical method on a liquid metal substrate (HSMG® graphene). The graphene was separated using chemical etching method or the electrochemical delamination method, by separating by means of electrolysis. During electrolysis, hydrogen is emitted on a graphene-covered of cathode (metal growth substrate) as a result of the voltage applied. The graphene layer breaks away from metallic substrate by gas accumulation between them. The results from these separation processes were evaluated by means of different tools, such as SEM, TEM and AFM microscopy as well as Raman Spectroscopy. In summary, the majority of analyses indicate that the graphene obtained as a result of hydrogen delamination possesses higher purity, smaller size and number of defects, its surface is smooth and less developed after the transfer process to the target substrate.
The presented article is a report on progress in photovoltaic devices and material processing. A cadmium telluride solar cell as one of the most attractive option for thin-film polycrystalline cell constructions is presented. All typical manufacturing steps of this device, including recrystalisation and junction activation are explained. A new potential field of application for this kind of device - the BIPV (Building Integrated Photovoltaic) is named and discussed. All possible configuration options for this application, according to material properties and exploitation demands are considered. The experimental part of the presented paper is focused on practical implementation of the high- temperature polymer foil as the substrate of the newly designed device by the help of ICSVT (Isothermal Close Space Vapour Transport) technique. The evaluation of the polyester and polyamide foils according to the ICSVT/CSS manufacturing process parameters is described and discussed. A final conclusion on practical verification of these materials is also given.