Magnetic nanocomposite Ba-ferrite/α-iron hollow microfiber: A multifunctional 1D space platform for dyes removal and microwave absorption

A facile gel-thermal selective reduction process was designed for the preparation of magnetic nanocomposite Ba-ferrite/α-iron hollow microfibers. The nanocomposite Ba-ferrite/α-iron microfibers were obtained after the reduction of the as-prepared Ba-ferrite/α-Fe2O3 microfibers at 375 °C for 1 h. SEM and TEM revealed that the nanocomposite Ba-ferrite/α-iron microfibers were constructed by plate-like and spherical particles with hollow structure. Dye removal experiments demonstrate that the combination of Ba-ferrite and α-iron can lead to larger numbers of methyl blue dye molecules removal from aqueous solution. This enhanced removal performance can be attributed to the unique nanocomposite structure, peculiar electron transfer, adsorption and reduction. These binary microfibers can also be used as absorbents for microwave absorption. For the Ba-ferrite/α-iron microfibers with designed mass ration of 1/4 reduced at 375 °C and a specimen thickness of 3.0 mm, the optimal reflection loss (RL) reaches −20.6 dB at 13.1 GHz, and the bandwidth exceeding −10 dB covers the whole X-band and 54% Ku-band. Hence, these magnetic nanocomposite Ba-ferrite/α-iron hollow microfibers can provide a multifunctional 1D space platform for dyes removal and microwave absorption.