Work

Wearable Janus‐Type Film with Integrated All‐Season Active/Passive Thermal Management, Thermal Camouflage, and Ultra‐High Electromagnetic Shielding Efficiency Tunable by Origami Process

Year: 2023

Type: article

Abstract: Multifunctional films with integrated temperature adjustment, electromagnetic interference (EMI) shielding, and thermal camouflage are remarkably desirable for wearable products. Herein, a novel Janus‐type multifunctional ultra‐flexible film is fabricated via continuous electrospinning followed by spraying. Interestingly, in the polyvinyl alcohol (PVA)/phase change capsules (PCC) layer (P 1 ), the PCC is strung on PVA fibers to form a stable “candied haws stick” structure that obviates slipping or falling off. The film with sufficient melting enthalpy (141.4 J g −1 ) guarantees its thermoregulation capability. Simultaneously, its high mid‐IR emissivity (90.15%) endows the film with radiative cooling properties (reducing temperature by 10.13 °C). Mechanical strength is significantly improved by superimposing a polylactic acid (PLA) layer (P 2 ) on its surface. By spraying a thin MXene layer on the PLA surface of P 2 P 1 film, the obtained (MXene/P 2 P 1 ) MP 2 P 1 film is endowed with satisfactory low‐voltage heating, photo‐thermal and superior thermal camouflage performance, achieving all‐season thermal comfort. Impressively, the flexible MP 2 P 1 film achieves enhanced EMI shielding effect from 50.3 to 87.8 dB through a simple origami process, which simplifies the manufacturing process of high‐performance EMI shielding materials. In brief, the multifunctional Janus‐type MP 2 P 1 film is an attractive candidate for future wearable products with personalized thermal management and anti‐electromagnetic radiation.

Source: Advanced Functional Materials

DOI: 10.1002/adfm.202212776