Enhanced dielectric losses in α-MnO2via protonation modulation

Abstract

MnO₆ octahedra without distortions in α-MnO₂ have a low dipole content, which limits their dielectric loss capabilities. Herein, we develop protonated MnO₂ with distorted MnO₆ octahedra for increased dipole numbers via a two-step hydrothermal method. In comparison with α-MnO₂, this protonated MnO₂ provides greatly improved dipole polarization loss capabilities, resulting in a reflection loss value of −19.1 dB with an effective absorption bandwidth of 3.3 GHz at a low thickness of 2 mm.