according to a report from advanced science news, scientists described in a new research paper a process for using a blade-coating approach to create large-area, macroscopic-assembled, free-standing and chemically stable graphene papers with adjustable thickness for use in potential personal thermal management devices.

wearable ptm device designs. (advanced science news)

the article noted that it is rare to see graphene papers being incorporated into devices of this kind, despite their enhanced properties of thermal conductivity and low electrical resistance.

“their gp allows for joule heating to 42°c using a low supply voltage of around 3.2 v,” the article continued. “it also provides passive cooling via thermal transmission from the body to the environment within 7 s, which is faster compared with that of normal cotton fiber.

“finally, it is highly durable, can be fabricated into a variety of designs (see figure), and can withstand over 500 bending cycles and wash times over 1500 min, suggesting its great potential in wearable ptm.”

the research was recently published in small. the abstract stated:

“freestanding, flexible/foldable, and wearable bifuctional ultrathin graphene paper for heating and cooling is fabricated as an active material in personal thermal management (ptm). the promising electrical conductivity grants the superior joule heating for extra warmth of 42 °c using a low supply voltage around 3.2 v.

“besides, based on its high out-of-plane thermal conductivity, the graphene paper provides passive cooling via thermal transmission from the human body to the environment within 7 s. the cooling effect of graphene paper is superior compared with that of the normal cotton fiber, and this advantage will become more prominent with the increased thickness difference.

“the present bifunctional graphene paper possesses high durability against bending cycles over 500 times and wash time over 1500 min, suggesting its great potential in wearable ptm.”

in addition to the personal thermal management devices reported above, graphene was also included in a flame retardant fabric that was recently unveiled at the textile and yarn expo in shanghai.

watch the video below to see the fabric in action: