Cr-doped VO2/ethyl cellulose composites with highly reversible and controllable electromagnetic interference shielding ability

Vanadium dioxide (VO₂) undergoes reversible metal–insulator transitions at critical temperature of 68 °C, rendering it promising for tunable electromagnetic applications. Here, Cr-doped VO₂/Ethyl cellulose (EC) composites are synthesized to raise the transition temperature to 87 °C while retaining shielding effectiveness values of 9.9–26.3 dB (X-band) and 10.2–25.2 dB (Ku-band). Notably, the surface temperature of material plateaus at 70 °C after exposure to one sun for 10 min, preventing passive phase transitions under light exposure. This work provides valuable insights into the design of intelligent electromagnetic interference shielding materials with active thermal regulation capabilities.