▎ 摘　　要

Molybdenum selenide (MoSe2), as a potential electromagnetic wave (EMW) absorber, its phase influence on the EMW absorption performance has not yet been investigated. Herein, we synthesized MoSe2 by a one-step hy-drothermal approach, while controlling the intensity of reduction process to modulate the phase of MoSe2. The influence of MoSe2 with different phases on the EMW absorption performance is intuitively revealed by comparing corresponding performances. Remarkably, 2H/1T-MoSe2 exhibit the optimal absorption performance with a minimum reflection loss (RLmin) of-52.3 dB@16 GHz and an effective bandwidth (EAB) of 6.4 GHz at 2.1 nm thickness, which cover the whole Ku band. Besides, to meet the growing demand for wearable electronics, a flexible microwave absorbing material with RLmin of-33.4 dB@9.1 GHz was created by constructing 2H/1T-MoSe2@RGO layered nanostructures on the surface of cotton fabric. Especially at the thickness of 3.3 mm, EAB can cover the whole X-band. Above composite fabrics also possess excellent self-cleaning and corrosion resistance as a result of layered nanostructures and hydrophobic coatings. This work not only provides a crucial reference for advancing the electromagnetic wave absorption performance via phase engineering, but also proposes an novel idea for the development of fiber-based multifunctional flexible microwave absorbing materials.