Investigation of polyesters as daytime radiative cooling materials

Abstract

We discovered that polyesters, particularly polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), are potential candidates for daytime radiative cooling (RC). A significant temperature drop was observed in both PET and PEN films when they were exposed to liquid nitrogen. In addition, their RC efficiency was compatible with previously reported RC materials such as polydimethylsiloxane and soda-lime glass. Polyesters have advantages over other RC materials in terms of chemical stability, moldability, and impact resistance. In particular, PET can be utilized for daytime RC of solar cells due to its transparency in the visible region.

Keywords:

• Daytime radiative cooling
• polyester
• polyethylene naphthalate
• PET

Subject classification codes:

• include these here if the journal requires them

Additional information

Funding

This work was partially supported by a Grant-in-Aid for Scientific Research (No. 19H02624) from the Japan Society for the Promotion of Science.