Coating V <sub>2</sub> O <sub>5</sub> @NaV <sub>6</sub> O <sub>15</sub> Nanofibers with PPy Toward Prominent Sensitivity, Thermal Dissipation, Electromagnetic Protection, Waterproofing, and Mechanical Properties
Baoxin Fan, Longqiong Pan, Ran Ji, Junzhe Shang, Jiali Liao, Qian Lin, Guoxiu Tong, Liyan Xie, Tong Wu
Abstract
Abstract Excellent mechanical flexibility, thermal conductivity, and microwave absorption are essential properties for multifunctional materials applied in next‐generation wearable electronics. However, it remains a great challenge to improve the incompatibility among these properties. Herein, high‐quantity V 2 O 5 @NaV 6 O 15 @PPy core‐shell nanofibers (CSNFs) are synthesized via a simple dissolution‐recrystallization and in situ redox polymerization process. Owing to regular, periodic, and stable sensing signals, their membrane can serve as a strain sensor to accurately detect word pronunciation and body movement. Their TPU films possess high strength, excellent hydrophobicity, and large thermal conductivity (3.56 W m −1 K −1 ); 7 wt.% load. Besides, the CSNFs exhibit efficient wide‐band microwave absorption (8.56 GHz) and RCS reduction (24.41 dBm 2 ) at a low load (7 wt.%), outperforming most other absorbers. The boosted performance can be ascribed to their 1D structure with multiple heterostructures and abundant defects, which generate conductive loss, diverse polarizations, multiple microwave scattering, and the cooperative heat transfer of electrons and phonons. Further analyses reveal their heat transfer and dielectric loss mechanisms based on the density of states, electric field distribution, and the phonon density of states. Overall, the V 2 O 5 @NaV 6 O 15 @PPy CSNFs are promising as multifunctional materials for applications in wearable strain sensing, thermal management, EM protection, and Radar stealth, particularly in extreme environments.