Synthesis and thermal characterization of sensible thermal heat storage phosphate mixtures as well as neutral composite material

Abstract

Both non-calcined form and calcined form of the phosphate mixtures are synthesized in atmospheric conditions and characterized with different measurement techniques. At low temperature, non-calcined mixture and at high temperature calcined mixture exhibit potential to be used as sensible thermal heat storage material due to their endothermic behaviour. Differential scanning calorimetry (DSC) technique was used to analyse the thermal behaviour. This measurement was done in atmospheric oxygen at 10 K min−1. The composite material was synthesized using calcined mixture with paint emulsion, and its thermal behaviour was studied in two thermal cycles using DSC measurement technique at 10 K min−1. Thermal behaviour of composite material qualifies it to be used as coating material in household applications due to its neutral behaviour towards thermal heat after two thermal cycles. Both non-calcined mixture with Eg = 2.32 eV at λmax 534 nm and calcined mixture with Eg = 2.15 eV at λmax 576 nm show semiconducting behaviour as the respective calculated band gap values fall in the semiconducting region.