Development of a disodium hydrogen phosphate dodecahydrate phase change material by incorporating activated hydro char and boron nitride for thermal energy storage in solar application

Phase change materials (PCM) have gained recognition worldwide as a powerful resource revolutionizing thermal storage material and managing heat in solar photovoltaic panels. Adversely, PCMs are found lacking in rigidity, have leakage issues, exhibit phase separation and undergo a supercooling process. Hence, the present study, aims to fabricate and characterize disodium hydrogen phosphate dodecahydrate (DHPD) as a base PCM material by integrating activated hydro biochar (A-HC) and boron nitride (BN) at various loading rates and demonstrate its efficacy as thermal energy storage (TES) material. In this study, we have applied various characterization techniques that include FTIR, XRD, SEM, BET, DSC, and TGA analysis for DHPD PCM with A-HC and BN at different loading values. Moreover, we also carried out the thermal conductivity assessment, enthalpy analysis, leakage test, degree of subcooling, corrosion stability for DHPD PCMs with varying values of A-HC and BN. Based on the results, it was observed that the composite DHPD PCM with 40 % A-HC and 2 % BN (DHPD PCM/A-HC5) was found to be more suitable in comparison to other composite PCM and pure DHPD PCM samples for TES application. The thermal conductivity for DHPD PCM/A-HC5 composite was determined to be 1.954 W/m. K, reduction in leakage was up to 4.8 %, degree of subcooling temperature difference was 14.1 °C and an enthalpy ranging from 86.12 kJ/kg to 124.82 kJ/kg was established. Further, copper (Cu) metal exhibited higher corrosion stability over other chosen metals for the composite sample DHPD PCM/A-HC5.