Giant barocaloric effects in natural graphite/polydimethylsiloxane rubber composites

Author(s)

Imamura, William ^{[1, 2]} ; Usuda, Erik Oda ^[3] ; Najar Lopes, Eder Socrates ^[1] ; Gomes Carvalho, Alexandre Magnus ^{[2, 3, 4]}

Affiliation

^[1] Univ Estadual Campinas, Fac Engn Mecan, BR-13083860 Campinas, SP - Brazil

^[2] Univ Estadual Maringa, Dept Engn Mecan, BR-87020900 Maringa, Parana - Brazil

^[3] Univ Fed Sao Paulo, Dept Engn Quim, BR-09913030 Diadema, SP - Brazil

^[4] Univ Estado Rio de Janeiro, Inst Fis Armando Dias Tavares, UERJ, Rua Sao Francisco Xavier 524, BR-20550013 Rio De Janeiro, RJ - Brazil

• Document type: Journal article
• Source: Journal of Materials Science; v. 57, n. 1 JAN 2022.
• Web of Science Citations: 0

Abstract

Solid-state cooling based on caloric effects is considered a viable alternative to replace the conventional vapor-compression refrigeration systems. Regarding barocaloric materials, recent results show that elastomers are promising candidates for cooling applications around room temperature. However, elastomers are insulating materials, which is a disadvantage that may compromise practical applications, since high heat transfer properties are typically desirable for more efficiency. Herein, barocaloric effects are investigated in natural graphite/polydimethylsiloxane rubber composites (NG/PDMS), in different concentrations of natural graphite. Adding natural graphite to PDMS, the adiabatic temperature change and the isothermal entropy change of the NG/PDMS composites reduce when compared to PDMS, but the composites still remain in giant barocaloric class and achieve an increase up to similar to 500% in thermal diffusivity and thermal conductivity. The results are promising for solid-state cooling based on barocaloric effect because the NG/PDMS composites combine different desired properties and are identified as better or similar among different barocaloric materials reported in the literature. (AU)

• FAPESP's process: 16/22934-3 - i-Caloric Effects
• Grantee: Alexandre Magnus Gomes Carvalho
• Support Opportunities: Regular Research Grants