PCM-containing bi-layered alkali-activated materials: A novel and sustainable route to regulate the temperature and humidity fluctuations inside buildings

Energy demand in the construction sector has continued to grow over the past years, despite the European commitment to promote energy efficiency. The development of multifunctional materials to tackle the energy consumption and improve the thermal performance of buildings is in huge demand. Herein, we report for the first time the synthesis of a bi-layered alkali-activated composite having a highly porous top-layer and a dense bottom-layer containing varying amounts of phase change material (PCM). This novel material can regulate the temperature swings inside buildings and simultaneously buffer the humidity levels to improve the comfort for inhabitants. Results show that the PCM content controls the specimens' mechanical and thermal performance, while the thin porous layer regulates their moisture buffer ability. A PCM incorporation of 30 wt% strongly reduces the indoor thermal fluctuation (up to 5 degrees C) compared to the reference cell. Additionally, this novel material showed high potential to control indoor humidity, as demonstrated by the very high practical MBV (2.71 g/m2 Delta%HR). These are promising results suggesting that these waste-derived materials can be an interesting tool towards the develop of sustainable and energy efficient buildings.

Automated summary

The synthesis of a bi-layered alkali-activated composite with highly porous top-layer and dense bottom-layer containing phase change material (PCM) is reported for the first time, showing potential to regulate temperature swings and humidity levels inside buildings. Results indicate that PCM content affects mechanical and thermal performance, while the thin porous layer influences moisture buffer ability.