Structure and thermal property relationships in the thermomaterial di-n-butylammonium tetrafluoroborate for multipurpose cooling and cold-storage

Abstract

Nowadays around 46% of food production around the world requires refrigeration, which is generally provided either by active vapour-compression (based on refrigerants with liquid-gas transitions) or passive cold-storage (based on...

Barocaloric Effects in Dialkylammonium Halide Salts

“…32,35,36 In addition, the effect of pressure on dialkylammonium halide phase transitions has not yet been investigated, though we note a somewhat similar compound (di-n-butylammonium tetrafluoroborate) was recently reported to exhibit large barocaloric effects. 37 Herein, we report a detailed investigation of barocaloric effects in symmetric dialkylammonium halide salts and demonstrate that, when appropriately designed, these materials exhibit properties that make them promising solid refrigerants.…”

“…The foregoing results establish dialkylammonium halide salts as a new class of highly tunable barocaloric materials with excellent energy density, reversibility, processability, and stability. Through a systematic investigation of barocaloric effects in these organic materials, this work contributes to the rapidly growing knowledge base around pressure-induced phase transitions in organic salts, 37,62,63 long-chain hydrocarbons, 45,64−66 and plastic crystals. 67−69 Efforts to further investigate thermal conductivity, dynamics of disordered phases, and barocaloric effects across a wider range of soft materials are currently underway in our laboratory.…”

“…Similar to 2D perovskites, dialkylammonium halides thus feature bilayers of hydrocarbon chains that are confined through hydrogen bonding interactions with 2D sheets of halide anions and can undergo reversible solid-state order–disorder transitions. Although the phase-change thermodynamics of many dialkylammonium halides has been investigated in detail at ambient pressure in the context of thermal energy storage, − the structural information available for this class of compounds is limited, making it challenging to gain mechanistic insights into their phase transitions and to establish structure–property relationships. ,, In addition, the effect of pressure on dialkylammonium halide phase transitions has not yet been investigated, though we note a somewhat similar compound (di- n -butylammonium tetrafluoroborate) was recently reported to exhibit large barocaloric effects . Herein, we report a detailed investigation of barocaloric effects in symmetric dialkylammonium halide salts and demonstrate that, when appropriately designed, these materials exhibit properties that make them promising solid refrigerants.…”

Pressure-freezing of dodecane: exploring the crystal structures, formation kinetics and phase diagrams for colossal barocaloric effects in n-alkanes

“…In this study we evaluate the colossal BC effect of jDSj = 778 J kg −1 K −1 in n-dodecane, driven by liquid-solid transition at ∼0.15 GPa and 295 K. This is the largest entropy change ever determined experimentally for a BC material to date. The jDSj values for selected state-of-the-art BC materials, 17,25,27,36,[43][44][45][46][47][48][49][50][51][52][53][54][55][56] are collated in Fig. 1.…”