| Popis: |
Concrete is the main material in civil engineering and heavily contributes in energy and environmental issues worldwide. A step forward here is to address energy management of buildings through innovations by overlapping construction and energy materials. An innovative example is a preparation of geopolymer materials in form of paste that could be developed into thin-film, in a conductive and transparent configuration, similar to transparent conductive oxide materials, for possible application in solar cells. Nowadays, in terms of geopolymers, more and more the focus is shifting from bulk to thin-film systems. Thereof, in this work we report on the level of structural and chemical changes which appear during the aluminosilicate curing conditions, grappling with configuration changing from bulk to thin-film. For this purpose, we examined conditions behind the reactions for obtaining mechanically and electrically optimized samples. Samples were characterised by DTA-TGA, FTIR, XRD, SEM and Impedance spectroscopy. In our system, amorphous premullite is used as a precursor for the aluminosilicate network. A gel state is reached after one hour provided the right solid to liquid ratio with activation solution was applied. Dry geopolymer block state is achieved after 24 hours of curing at ambient temperature. The crucial advantage of such a course of preparation is the room temperature curing which is not the case for geopolymer systems composed of common aluminosilicate precursors that require higher curing temperatures. Obtained results enable a better understanding of the influence of chemical composition and homogeneity of constituents on the geopolymerization, as well as structural, morphological and electrical characteristics of studied samples, all intending to optimize the process of geopolymer preparation in a thin-film configuration. |
