Influence of nano-ZrO₂ on the mechanical and thermal properties of high temperature cementitious thermal energy storage materials

The mechanical and thermal properties of high temperature aluminate cementitious thermal energy storage materials modified with nano-ZrO₂ are investigated. The influence of nano-ZrO₂ amounts on the performance, such as compressive strength, thermal conductivity, volume heat capacity, and thermal expansion coefficient, of hardened composite cement pastes were studied for future solar thermal energy materials with better performance. It is observed that before heating the pore structure and compressive strength are both optimized at the optimum nano-ZrO₂ amount of 1 wt%. At the same time, thermal conductivity and volume heat capacity of the composite paste enriched with nano-ZrO₂ improved after heating at 350 and 900 C compared with that of pure paste, which is very favorable for high thermal storage materials application. XRD, TG-DSC, FTIR, and MIP were used to characterize the mineral phases, the hydration/dehydration evolution, the chemical bonding, and the pore structures of the hydration products, respectively.