Two birds with one stone: Superhelical chiral polypyrrole towards high-performance electromagnetic wave absorption and corrosion protection

It is of great significance to find high-efficiency microwave absorbing materials with corrosion resistance to improve the environmental adaptability and survivability of military targets in harsh chemical environment. Corrosion will lead to the degradation of its microwave absorption performance, and hinder its further application in the actual environment. Herein, a new strategy of chiral small molecule soft-template was proposed for the synthesis of superhelical chiral polypyrrole nanofibers, which can be developed as a promising high-performance anticorrosive microwave absorber. The helical polypyrrole nanofibers (HPPy) were found to enhance impedance matching and electromagnetic wave attenuation ability due to the enhanced dielectric loss and additional magnetic loss from electromagnetic cross-polarization induced by supramolecular chirality. The optimal HPPy shows excellent microwave absorption performance with two reflection loss peaks of − 44.5 dB and − 11.9 dB respectively, which can extend the effective absorption bandwidth up to 5.4 GHz at a loading of only 6 wt%. Furthermore, the correspongding HPPy-EP coatings can give a long-term remarkable corrosion protection capability (96.83%) after 21 days of immersion in corrosive mediumin due to their spatial barrier effect and the passivation effect. The superhelical chiral polypyrrole could open new avenues toward excellent anticorrosive microwave absorption, especially in marine environment.