AC electrical properties of geopolymers with carbon black admixture

25th International Conference and Meeting of Departments, CONSTRUMAT 2019

Petíková, M.^1 ; Fiala, L.^1

Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, Thákurova 7, Prague 6

166 29, Czech Republic^1

关键词: AC electrical properties;    Capacitive character;    Electrical behaviors;    Electrically conductive;    Functional properties;    High frequency HF;    Percolation thresholds;    Thermoelectric energy;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/549/1/012044/pdf
DOI  :  10.1088/1757-899X/549/1/012044

来源: IOP

【 摘 要 】

Geopolymers as competitors to the cement-based construction materials are intensively studied in the present. Their competitiveness mainly arises from their high strength, favourable development of hydration heat at early age, good chemical resistance and thermal stability. Further qualitative improvement of functional properties can be achieved by adding electrically conductive admixtures. In an appropriate amount (called percolation threshold), mechanical properties remain reasonable and electrical properties become sufficient to ensure evolution of heat by acting of an external power source (self-heating), to detect material damage (self-sensing) or to harvest thermoelectric energy (energy harvesting). In this paper three geopolymers with different dosages of carbon black (CB) admixture (0 wt. %, 4 wt. %, 10 wt. %) were studied by means of LCR bridge AC measurements. It was observed significant difference in electrical behavior of the studied geopolymers. 0 wt. % geopolymer exhibited highly capacitive character, 4 wt. % geopolymer was slightly shifted to resistive behavior and 10 wt. % geopolymer behaved like resistor even to high frequencies with reasonable resistance which indicates its possible self-heating ability.