Rutile TiO₂ nanorod with anomalous resonance for charge storage and frequency selective absorption

TiO₂ is not among the traditional electromagnetic (EM) absorbing material candidates owing to its poor response in the EM wave region. Although the EM wave absorption performance can be improved by hybrid and/or hydrogenated TiO₂, the difficulty and risk of the experimental process are increased. Herein, rutile TiO₂ nanorod was successfully prepared by two-step method. The analysis of dielectric properties exhibits that rutile TiO₂ nanorod has excellent charge storage capacity. The results of EM wave absorbing performance show that impedance matching caused by anomalous resonance leads to frequency selective absorption. Such anomalous resonance is due to the resonant polarization of ionic clusters formed by oxygen ions and titanium ions. Moreover, metastructure design shows that the EM absorption frequency and the EM wave absorption bandwidth can be tuned through the design of metamaterial. Our founding will broaden the field of vision for the design of EM wave absorbing materials in the future.