Study on Graphene Oxide Modified Inorganic Phase Change Materials and Their Packaging Behavior

Abstract

We prepared the nano-inorganic phase-change “alloy” materials through the modification of Na₂SO₄•10H₂O using Na₂HPO₄•12H₂O and GO nano-nucleating agent, and further investigated their thermophysical properties such as melting/solidification temperatures and enthalpies via differential scanning calorimetry. When the weight ratio of Na₂SO₄•10H₂O and Na₂HPO₄•12H₂O was 8:2 and the weight ratio of graphene oxide was 0.5% of phase change material, the phase change “alloy” material showed excellent performances, specifically, the melting temperature and latent heat were found to be 22 °C and 190 J/g with a degree of subcooling decreased from 8.6°C to 2.1°C. In order to extend the application of the phase change “alloy” material to building energy saving field, it was adsorbed on expanded glass beads under vacuum and further covered with diatomite. When the adsorption rate of EGB (volume) and PCAM (weight) was 2.5:1, the particle size of diatomaceous earth was found to be 3.6μm, while the best packaging result was obtained with the melting temperature and latent heat being 21°C and 135J/g, and no leakage was observed.

Keywords

inorganic PCM / GO / DE / packaging / thermophysical properties

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