Room-temperature barocaloric effect in [Fe(pap-5NO2)2] spin-crossover material

We examine the pressure dependence of the spin-crossover transition in [Fe(pap-5NO2)2] that occurs near room temperature. We employ a combination of high-pressure calorimetry and powder X-ray diffraction measurements, conducted both under variable-pressure and variable-temperature conditions. Both m...

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Detalles Bibliográficos
Autores: Gracia, David, Cuartero, Vera, Popescu, Catalin, Trapali, Adelais, Mallah, Talal, Boillot, Marie-Laure, Blasco, Javier, Subías, Gloria, Evangelisti, Marco
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2025
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/399481
Acceso en línea:http://hdl.handle.net/10261/399481
Access Level:acceso abierto
Descripción
Sumario:We examine the pressure dependence of the spin-crossover transition in [Fe(pap-5NO2)2] that occurs near room temperature. We employ a combination of high-pressure calorimetry and powder X-ray diffraction measurements, conducted both under variable-pressure and variable-temperature conditions. Both methods indicate that the spin-crossover transition shifts linearly to higher temperatures with increasing pressure, while simultaneously exhibiting an increase in the width of the thermal hysteresis. We report a giant barocaloric effect, revealing isothermal entropy changes in the 70–79 J kg−1 K−1 range and adiabatic temperature changes between 20 and 26 K for a pressure change of 2.0 kbar. Although the effect diminishes under reversible conditions, it remains substantial, with values of 70 J kg−1 K−1 and 14 K, respectively.