Facile construction of Janus MXene/cellulose/ZnO membrane with EMI shielding property for on-demand personal thermal management

To handle the increasingly harsh living space caused by extreme temperatures and floods of electromagnetic waves, wearable materials have been attracting much attention for decades due to their good versatile compatibility and precise utility. In this work, a Janus MXene/cellulose/ZnO nanorods membrane for accurate on-demand personal thermal management and electromagnetic interference shielding was fabricated via hydrothermal treatment and vacuum-assisted filtration, followed by a hydrophobization process. The ZnO nanorod side of obtained Janus membrane exhibits a high visible reflectance (96.3%) and infrared emissivity in the atmospheric window band (0.837). The corresponding visible absorption and average infrared reflectivity (5-25 mu m in wavelength) of the MXene side are over 90% and 0.7, respectively. Remarkable temperature differences on both sides (7 degrees C increment on MXene side and 5 degrees C reduction on ZnO side compared to bare wooden board) were achieved in the validation test under direct sunshine, reflecting to the great optical properties and radiative thermal management performances of the obtained membrane. Moreover, the water contact angles (>= 120 degrees) indicated the hydrophobicity and associated stain resistance of this membrane. Active Joule heating and electromagnetic interference shielding characteristics have been successfully introduced into the Janus membrane by means of the integration of MXene. A rapid increase in temperature to 75 degrees C was attained within a 1 min of low voltage (2 V) applying. The effectiveness of the electromagnetic shielding (similar to 30 dB) was higher than the commercial shielding materials. The results in general, provide a promising solution to protecting people from temperature extremes and electromagnetic waves interference in modern living space.

Automated summary

Wearable materials have attracted much attention for their versatile compatibility and utility in addressing the harsh living space caused by extreme temperatures and electromagnetic wave floods. In this study, a Janus MXene/cellulose/ZnO nanorods membrane was fabricated for accurate personalized thermal management and electromagnetic interference shielding. The obtained membrane exhibited great optical properties and radiative thermal management performances, with remarkable temperature differences achieved on both sides. Furthermore, the membrane showed excellent hydrophobicity and stain resistance, along with active Joule heating and superior electromagnetic interference shielding characteristics.