Case studies on elastocaloric technology-based solid-state cooling: A focus on materials and applications

Abstract

Elastocaloric-based solid-state cooling has recently emerged as a promising, sustainable, energy-efficient, and Freon-free approach. In this context, the elastocaloric effect mechanism has been adopted and illustrated in this review paper. A bibliometric visualization that includes the most used keywords (authors and indexed), the countries and journals with the highest publications and citations, and the most cited authors during the last 25 years has been conducted to estimate the elastocaloric materials and applications recent progress, significance, maturity, and research gaps. Moreover, a colossal comprehensive overview of elastocaloric materials and applications has also been covered, emphasizing trends, challenges, and applicability of elastocalorics. Finally, future perspectives were discussed, focusing on applications, scalable production, and innovative materials. According to the findings, binary alloys demonstrated adiabatic temperature changes exceeding 25 K and entropy changes up to 50 J/kg·K, yet they face fatigue limitations. Additionally, ternary and quaternary alloys provided improved cyclic durability (>10,000 cycles) and tunable transformation temperatures, while natural rubber offered exceptional fatigue life (>170,000 cycles), albeit with smaller adiabatic temperature changes (≈4–8 K). Emerging polymeric systems enhanced with nanofillers achieved exceptional entropy changes (≈200 J/kg·K) and excellent cyclic stability. The reviewed applications showcased a coefficient of performance ranging from 3 to 8, depending on material class and configuration.