Facile synthesis of coral cauliflower-like polypyrrole hemispheres toward screening electromagnetic interference pollution

In this study, coral cauliflower-like polypyrrole (PPy) hemispheres are synthesized on an alumina substrate via a simple chemical oxidative polymerization route. The stony coral-like morphology of PPy hemispheres acts as a conducting trap in absorbing electromagnetic (EM) radiation via multiple internal reflections. A PPy thin film deposited at 0.2 M pyrrole concentration shows a minimum reflection loss (RL) of -30.80 dB (99.9% microwave absorption) at the frequency of 14.2 GHz, and the highest total shielding effectiveness achieved is -18.3 dB at 16.8 GHz at 4.38 mu m film thickness. The thin films exhibit excellent microwave absorption ability at low thicknesses, and the effective absorption bandwidth (RL < -10 dB) attains a high value of 2.2 GHz in the frequency range of 13-15.2 GHz. These findings can help researchers to enhance the EM wave absorption characteristics in a broad frequency region using lightweight intrinsically conducting polymers.

Automated summary

The study successfully synthesized coral cauliflower-like polypyrrole (PPy) hemispheres on an alumina substrate, which show excellent microwave absorption ability. The PPy thin film deposited at specific concentration exhibits strong absorption of electromagnetic radiation and can enhance the absorption characteristics of EM waves in a broad frequency region.