Conversion of aquatic weed water-hyacinth to conducting and microwave shielding material-a scientific approach

Abstract

This work reports the fabrication of microwave absorbing hybrid composites of nickel ferrite (NF), poly aniline (PANI) and natural fibre extracted from water hyacinth (WHF). In-situ polymerisation method of aniline using ammonium peroxydisulphate is adopted for the synthesis of PANI, PANI-WHF and PANI-WHF-NF composites. The structural and morphological characterisations are done by XRD, FT-IR and scanning electron microscope analysis. Thermal stability of the samples is established with thermogravimetric analysis. Dc conductivity studies ensure the semiconducting nature of binary (PANI-WHF) as well as ternary (PANI-WHF-NF) composites. Microwave shielding effectiveness (SE) of the composites are studied in the frequency range of 6–8.5 GHz. Binary composites give lower SE, which further improves with the inclusion of NF to about 17 dB. The study establishes the conversion of WHF to conducting and microwave shielding material. The highlights of the work include the synthesis of PANI fibre ferrite composites through in-situ polymerization method, also addition of fibres increase the mechanical strength of the composites, the composites exhibit shielding effectiveness of 17 dB in the frequency range of 6–8.5 GHz and the composite material exhibit good conductivity in the range of 10 −1 Scm−1–10 −3 S cm −1.