Self-template and in-situ polymerization strategy to lightweight hollow MnO2@polyaniline core-shell heterojunction with excellent microwave absorption properties

Abstract

Nowadays, high-frequency electromagnetic pollution makes the lightweight and high-efficiency absorption materials become the research hotspot. In this paper, the hollow structure MnO2@PANI microsphere composite was reasonably synthesized by self-template strategy and in-situ polymerization. Coating conductive polyaniline (PANI) on the modified surfaces of MnO2 microsphere not only can improve the impedance matching and microwave absorption ability, but also solve the drawback of low loss intensity as well as narrow absorption band of pure MnO2. The conductive polymer PANI conductance loss, MnO2-PANI multiple interfacial polarization and multiple reflection loss synergy endows hollow MnO2@PANI microsphere excellent microwave absorption performance. The RLmin of hollow MnO2@PANI microsphere is −52.06 dB at 8.48 GHz and has a wide absorption of 4.56 GHz. Those positive results show that the pure dielectric MnO2@PANI microsphere material with a multi-interface hollow core-shell structure prepared from a template is a lightweight and efficient absorbent.