Giant barocaloric effects over a wide temperature range in superionic conductor AgI.

Area of Science:

• Materials Science
• Thermodynamics
• Solid-State Physics

Background:

• Barocaloric effects, driven by pressure-induced temperature changes, are significant near ferroic phase transitions.
• Previous research focused on materials with magnetic or electrical order.

Purpose of the Study:

• To investigate giant inverse barocaloric effects in the solid electrolyte silver iodide (AgI).
• To explore the potential of AgI for solid-state cooling applications.

Main Methods:

• Experimental measurement of barocaloric effects in AgI near its superionic phase transition (~420 K).
• Application of hydrostatic pressure changes (2.5 kbar) over a wide temperature range.
• Characterization of isothermal entropy and adiabatic temperature changes.

Main Results:

• Demonstrated giant inverse barocaloric effects in AgI.
• Observed large and reversible barocaloric effects with significant refrigerant capacity.
• Achieved peak isothermal entropy change of 60 J K⁻¹ kg⁻¹ and adiabatic temperature change of 18 K at 390 K.

Conclusions:

• The observed barocaloric effects in AgI surpass previously recorded values for barocaloric materials.
• This study encourages research into solid electrolytes for barocaloric applications.
• The findings support the development of new solid-state cooling technologies.