G. Pishevarz, H. Erfan Niya, E. Zaminpayma,
Volume 37, Issue 3 (12-2018)
Abstract
Abstract: In this work, the amounts of the adsorption of conjugated polymers onto graphene/ graphene oxide were examined by reactive force-field molecular dynamics simulation. The polymers were poly(3-hexylthiophene) (P3HT) and poly(phenothiazine vinylene-polythiophene)(PTZV-PT). The length and width of the graphene sheet were 95.19 Å and 54.16 Å, respectively. The graphene oxide sheets with different oxidation percentages were considered. The molecular dynamics simulation results demonstrated a higher amount of adsorption onto graphene oxide sheets in comparison to graphene; furthermore, poly(phenothiazine vinylene-polythiophene) revealed a larger amount of adsorption in comparison with poly(3-hexylthiophene) in both functionalized groups of hydroxyl and epoxy. Also, some structural properties of polymers, such as radius of gyration of polymer and radial distribution function, were calculated at different reactive sites.
N. Ghobadi, S. A. Hosseini Moradi, M. Amirzade,
Volume 40, Issue 4 (3-2022)
Abstract
In this research, cobalt ferrite powders (CoFe2O4) and cobalt ferrite/reduced graphene oxide composite (CoFe2O4/RGO) were synthesized by the co-precipitation method. The phase structure, morphology, magnetic properties, and microwave absorption properties of the produced samples were investigated through various techniques. X-ray diffraction test indicated the successful formation of pure CoFe2O4 and its composites with RGO. According to the Scanning electron microscopy (SEM) images, most pure and composite samples’ particles were formed in a semi-spherical shape. The VNA test results showed the saturation magnetization of CoFe2O4 and the composite containing 5 wt.% and 10 wt.% of RGO, 71.6, 56, and 37 emu/g, respectively. Also, the network analyzer results demonstrated the maximum reflective losses in the X-band range due to the impact of microwaves on CoFe2O4 te was -5.5 db. This amount reached 21.5 dB with the addition of 10 wt.% RGO. Also, the wave input increased from 41% for the pure CoFe2O4 to 99.5% for the sample containing 10 wt.% RGO.
