Characterizations and melting analysis of (amine) group-functionalized graphene mixed/doped with paraffin wax as phase change material for thermal management and thermal energy storage applications

Herein, the energy storage performance of amine (NH2)-functionalized graphene mixed with paraffin wax (PW) which comprises the advanced phase change material (PCM) is studied. The amine-functionalized graphene is mixed with PW in four different volume percentages like 0.25 volume %, 0.5 volume %, 0.75 volume %, and 1 volume %. Its thermal performance is measured in terms of accumulated or stored energy at three different flow rates 6.25, 12.5 and 25 ml/s of the heat transfer fluid (HTF) which is water, passing through the spiral-coiled heat exchanger surrounded by this hybrid/advanced PCM. This apparatus for measuring the thermal energy stored is known as thermal energy storage system (TESS). In case of NH2-functionalized graphene mixed with paraffin wax the charging (melting) time decreases by 12.5-43.75% for the HTF flow rate 6.25 ml/s, 13.33-53.34% for HTF flow rate 12.5 ml/s and 23.07-61.5% for the HTF flow rate 25 ml/s over pure paraffin wax owing to increasing percentage and thermal conductivity of NH2 group-functionalized graphene in paraffin wax. This advanced energy material is also characterized using material characterizations techniques like FTIR, XRD, FESEM, EDS, TGA, DSC, thermal conductivity and thermal diffusivity tests which help in determining the structure and properties.