Cobalt phosphate-based composite with wall care putty as building envelope material for thermal energy storage

Abstract

The four different thermal energy storage composites were synthesized by charging Co-3(PO4)(2)center dot xH(2)O with wall care putty (Korean make) in aqueous media. These four different composites are abbreviated as A1, A3, A4 and A5 having composition 0.46 %, 1.00 %,1.63 % and 2.22 % of Co-3(PO4)(2)center dot xH(2)O, respectively. Differential Scan-ning Calorimeter (DSC) was used to measure specific heat capacity (C-P) for all above composites. Among all composites, the C-P = 1.34 Jg(-1)K(-1) is found maximum for composite A5 at 339 K in N-2 atmosphere. The highest heat storage density is also observed, 80.95 similar to 88.83 kJ kg(-1) , for composite A5 in temperature range 336 K to 342 K for storing heat up to similar to 13 min. The optical band gap (E-g) is calculated using Tauc and Menth as well as Kubelka-Munk function for all composites and all found insulator. The calculated crystallite size of composite A3 is similar to 400 nm.