An Electrical Switch-Driven Flexible Electromagnetic Absorber

The development of a thin, tunable, and high-performance flexible electromagnetic (EM) absorbing device that aims to solve signal interference or EM pollution is highly desirable but remains a great challenge. Herein, demonstrated is a flexible electrical-driven device constructed by an insulated organic-polymer substrate, carrier transmission layer, and core-shell structured absorber, enabling a narrow and tunable effective absorption region (f(E) < 2.0 GHz) by controlling the external voltage toward this challenge. As a key design element, the selected absorber consists of an Sn/SnS/SnO2 core and C shell, which exhibits an exceptional dielectric-response ability at a small voltage, which is attributed to desirable carrier mobility and excitable carriers. Multiple f(E)-tuning regions (maximum up to 7.0), covering 90% of C-band can be achieved for Sn/SnS/SnO2@C-based flexible device by selecting a low voltage (2-12 V). The strategy developed here may open a new avenue toward the design of flexible intelligent EM device for practical applications.