A novel ‘one-pot’ synthetic method for preparation of (Ni0.65Zn0.35Fe2O4)x–(BaFe12O19)1−x nanocomposites and study of their microwave absorption and magnetic properties

Chemically Room Temperature Crosslinked Polyvinyl Alcohol (PVA) with Anomalous Microwave Absorption Characteristics

Polyvinyl alcohol (PVA) is a great interest polymer due to its excellent film-forming, emulsifying, microwave dielectrics and adhesive properties. However, PVA is a water-soluble synthetic polymer making it susceptible to environmental factors. In this work, PVA is crosslinked at room temperature using divinyl sulfone (DVS) as a crosslinker, and the obtained crosslinked PVA (XPVA) is water-insoluble. Crosslinking mechanism is proposed, thermal and microwave dielectric properties of X-PVA are studied. The studies revealed that X-PVA has better thermal stability and microwave absorption properties. The obtained minimum reflection loss (RL) of X-PVA is -23 dB (filler-free) with entire X-band (8.2-12.4 GHz) absorption bandwidth (RL ≤ -10 dB), indicating excellent microwave absorption properties. Artificial neural network (ANN) predicted RL of X-PVA also matched well with the experimental data. Electromagnetic power simulation suggests that the microwave power absorption density due to the dielectric loss is intrinsically predominant in X-PVA compared to the pristine PVA. Further, the ratio of electromagnetic energy to heat energy conversion power (absorption) of X-PVA is much higher than pristine PVA, indicating the suitability for self-powered devices. X-PVA also fulfils many commercial requirements such as bulk level facile synthesis, large area fabrications, ultralight, and inexpensive.

Preparation and electromagnetic wave absorption properties of FeNi3 nanoalloys generated on graphene–polyaniline nanosheets

The ternary nanocomposites of rGO–PANI–FeNi₃ were successfully synthesized by combining polymerization with hydrothermal reduction reaction.

A simple ‘in situ’ co-precipitation method for the preparation of multifunctional CoFe2O4–reduced graphene oxide nanocomposites: excellent microwave absorber and highly efficient magnetically separable recyclable photocatalyst for dye degradation

Here, an ‘in situ’ co-precipitation reaction method has been reported for the preparation of CoFe₂O₄–RGO (CF–RGO) nanocomposites.