Multifunctional wearable thermal management textile fabricated by one-step sputtering

Abstract

A single wearable device that seamlessly integrates all desirable functions is in urgent demand. However, the reported approaches to design such a device can only integrate two or three functions as a compromise owing to the mutual restraint between seemingly unrelated functions. In this study, using a ‘one-stone-five-birds’ strategy, an all-in-one thermal management textile containing Ag/Ti–TiO2 multilayer films (only 893 nm in thickness) was produced by a simple one-step magnetron sputtering process. Firstly, the bottom Ag layer acted as a material with low emissivity for passive heating and excellent conductivity for Joule heating (60.2 °C at 3 V). Additionally, this layer was capable of electromagnetic interference shielding (31 dB after 5000 stretching cycles). Secondly, a nano-gradient Ti–TiOx wavelength-selective absorber was used to achieve outstanding photothermal conversion (94.1 °C under 1 kW/m2 irradiation and 88.1 °C after 10 000 stretching cycles). Finally, the outermost TiO2 layer played two roles: as an anti-reflective layer to further improve sunlight absorption and to reduce the surface energy for robust superhydrophobicity. The contact angle of a water drop on the surface of the NSMTs always remained above 150° after various mechanical treatments, such as 10 000 stretching cycles and 2000 tape-peeling cycles. Owing to the overall considerations and synergistic enhancement, all of these functions exceeded or matched those of the state-of-the-art materials in recently reported studies. This study represents a crucial breakthrough for constructing high-performance flexible wearable devices.