Large barocaloric effect in binary fatty alcohols driven by solid-liquid phase transition near room temperature

The barocaloric effect, a promising green refrigeration technology, utilizes pressure-induced phase transitions to generate substantial entropy and temperature changes, offering an eco-friendly alternative to conventional gas-compression systems. In this study, a large barocaloric effect is demonstrated in a binary fatty alcohol system near its solid-liquid transition temperature. Specifically, an isothermal entropy change of up to 611 J kg⁻¹ K⁻¹ is achieved at 299 K under an easily accessible pressure of 100 MPa, with a large reversible isothermal entropy change of 553 J kg⁻¹ K⁻¹. This corresponds to an estimated adiabatic temperature change of 39.6 K, which is highly competitive with traditional refrigerants such as R134a. Furthermore, Raman spectroscopy reveals that pressure release in the liquid phase promotes the formation of gauche conformers. This structural change drives the liquid-solid transition, resulting in a significant configurational entropy change. Ultimately, this work presents a promising solid-liquid phase-change material for practical and efficient barocaloric refrigeration.