In Situ Synthesis of Fe3O4 Nanoparticles and Wood Composite Properties of Three Tropical Species

Abstract

Magnetic wood is a composite material that achieves harmony between both woody and magnetic functions through the active addition of magnetic characteristics to the wood itself. In addition to showing magnetic characteristics, magnetic wood offers low specific gravity, humidity control and acoustic absorption ability. It has potential for broad applications in the fields of electromagnetic wave absorption, electromagnetic interference shielding, furniture, etc. This work reports on the synthesis of Fe3O4 nanoparticles (NPs) in wood from three tropical species (Pinus oocarpa, Vochysia ferruginea and Vochysia guatemalensis) using a solution of iron (III) hexahydrate and iron (II) chloride tetrahydrate with a molar ratio of 1.6:1 at a concentration of 1.2 mol/L ferric chlorate under 700 kPa pressure for 2 h. Afterward, the wood samples were impregnated with an ammonia solution with three different immersion times. The treated wood (wood composites) was evaluated for the weight gain percentage (WPG), density, ash content and Fe3O4 content by the Fourier transform infrared spectroscopy (FTIR) spectrum, X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The results show that the species P. oocarpa had the lowest values of WPG, and its density decreased in relation to the untreated wood, with lower ash and Fe3O4 NP content. The XRD and some FTIR signals associated with changes in the wood component showed small differences from the untreated wood. Fe3O4 NPs presented nanoparticles with the smallest diameter of (approx. 7.3 to 8.5 nm), and its saturation magnetization (Ms) parameters were the lowest. On the other hand, V. guatemalensis was the species with the best Ms values, but the wood composite had the lowest density. In relation to the different immersion times, the magnetic properties were not statistically affected. Finally, the magnetization values of the studied species were lower than those of the pure Fe3O4 nanoparticles, since the species only have a certain amount of these nanoparticles (NPs), and this was reflected proportionally in the magnetization of saturation.

Silver Nanoparticles and Chitosan Oligomers Composites as Poplar Wood Protective Treatments against Wood-Decay Fungi and Termites

“…In terms of efficacy against T. versicolor, the results obtained in this study were less favorable than those reported by Casado et al [18] in poplar wood treated through vacuum-pressure impregnation of AgNPs solutions at 5 ppm after 16 weeks (ML = 8.94% vs. 30.15% in this study). Moya et al [20,21] also observed enhanced resistance to degradation by T. versicolor in 12 tropical commercial wood species treated with a solution of AgNPs. Weight loss percentages ranged from 7 to 11% after four months, which were lower than those reported herein, but it is worth noting that a significantly higher concentration (50 ppm AgNPs + ethylene glycol) was employed.…”

“…The application of silver nanoparticles (AgNPs) has become increasingly popular for enhancing diverse wood properties, including resistance to biological degradation, water absorption capacity, and dimensional stability. These improvements are achieved through both depth and surface treatments, spanning various concentrations of AgNPs [16][17][18][19][20][21][22][23][24].…”

Modification of Fast-Growing Wood into Magnetic Wood with Impregnation Method Using Fe3O4 Nanoparticles

“…Considering its easy processing, excellent magnetic properties, and increased physical properties, magnetic wood is an interesting new function for building materials, decoration, electromagnetic wave absorbers, massage furniture, and heat conductor (Gan et al 2017;Moya et al 2022). However, wood is an insulating material, so magnetic wood produces a relatively low magnetic field and belongs to the category of soft magnetic materials (Wahyuningtyas et al 2022).…”