Empowering CO2Eco-Refrigeration With Colossal Breathing-Caloric-Like Effects in MOF-508b

Abstract

[Abstract] Today,≈20% of the electric consumption is devoted to refrigeration; while,≈50% of the final energy is dedicated to heating applications. In this scenario,many cooling devices and heat-pumps are transitioning toward the use ofCO2as an eco-friendly refrigerant, favoring carbon circular economy.Nevertheless, CO2still has some limitations, such as large operatingpressures (70–150 bar) and a critical point at 31°C, which compromisesefficiency and increases technological complexity. Very recently, an innovativebreathing-caloric mechanism in the MIL-53(Al) compound is reported, whichimplies gas adsorption under CO2pressurization boosted by structuraltransitions and which overcomes the limitations of stand-alone CO2. Here,the breathing-caloric-like effects of MOF-508b are reported, surpassing by40% those of MIL-53(Al). Moreover, the first thermometry device operating atroom temperature and under the application of only 26 bar of CO2ispresented. Under those conditions, this material presents values of𝚫������T≈30 K, reaching heating temperatures of 56°C and cooling temperatures of−10°C, which are already useful for space heating, air-conditioning, foodrefrigeration, and freezing applications.