Effects of additives on the subcooling behavior of Al2(SO4)3⋅18H2O phase transition

• We discuss the reaction mechanism between additive nano-TiO2 and Al2(SO4)3⋅18H2O.
• We discuss the reaction mechanism between additive gelatin and Al2(SO4)3⋅18H2O.
• The subcooling temperature decreased to 3.1 °C with specific additives.

An experimental device for studying subcooling behavior was fabricated, and the subcooling curves of Al2(SO4)3⋅18H2O were drawn. The effects of nucleating agent, interface modifier agent, and deionized water addition were studied, and the mechanism was discussed. The results showed that the subcooling temperature of Al2(SO4)3⋅18H2O decreased to 3.1 °C with 1.5% nano-TiO2 (20 nm), 2% gelatin, and 10% deionized water.