3D printed barocaloric composites for environmentally friendly thermal energy management

Abstract

Our society is experiencing an accelerated technological transition to reach net zero emissions by 2050, where the decarbonization of heating and cooling systems is a key aspect. In this work, we describe two new solid-state barocaloric materials, [C₁₂H₂₅NH₃]₂MnCl₄ and [C₁₂H₂₅NH₃]₂MnBr₄, with colossal barocaloric effects of ΔS > 200 J K⁻¹ kg⁻¹, which are already reversible under operating pressures of 500 bar. In addition, we introduce the first 3D printable barocaloric composite using a pressure transmitting matrix and thermal conductive additives, which is formed in the shape of a heat exchange gyroid. This innovative proof-of-concept demonstrates a new strategy to enhance the thermal performance, chemical stability and technological integration of the emerging family of barocaloric compounds. In addition, we identify emerging technologies (beyond traditional refrigeration) where thermal management is critical and that match the operating temperature and pressure range of the barocaloric materials obtained here, namely, lithium-ion batteries and hydrogen fuel cells.