Exceptional comprehensive barocaloric performance in three-dimensional hybrid perovskite [Et3P(CH2)2F][Mn(dca)3] compound near room temperature

Abstract

Barocaloric (BC) refrigeration materials have rapidly emerged as a promising alternative for solid-state cooling applications, owing to their absence of system selectivity and colossal entropy change. However, most hybrid materials lack comprehensive performances in multiple barocaloric metrics (such as isothermal entropy change, adiabatic temperature change, barocaloric efficiency, refrigeration capacity, and critical driving pressure), leading to tremendous difficulties in the application of solid-state refrigeration. In this work, we report a kind of phosphonate 3D hybrid perovskite, [Et3P(CH2)2F][Mn(dca)3], as a barocaloric material, which features a monoclinic to orthorhombic phase transition near room temperature. The [Et3P(CH2)2F][Mn(dca)3] compound not only has excellent reversible isothermal entropy changes (ΔSrev ∼ 186.4 J kg−1 K−1 at 90 MPa), reversible adiabatic temperature change (ΔTrev ∼ 27.6 K at 90 MPa), and barocaloric coefficient (|dTt/dp| ∼ 0.33 K MPa−1) but also exhibits a relatively large refrigerant capacity (RCrev ∼ 2708 J kg−1 at 90 MPa) and critical driving pressure (Psat ∼ 90 MPa), which makes this compound a competitive candidate for room-temperature solid-state refrigeration.