Tailoring magnetic properties of Fe3O4 nanocomposites with amine-functionalized MWCNT for optimal hyperthermia performance

This study underscores the potential of nanocomposites of magnetite (Fe₃O₄) with amine functionalized multi-walled carbon nanotube (MWCNT) for applications in magnetic hyperthermia therapy, by optimizing the amine-functionalized MWCNT concentration to maintain favorable interactions with Fe₃O₄, avoiding excessive aggregation, and maximizing the hyperthermia performance. The magnetic property analysis revealed that the presence of amine-functionalized MWCNTs influenced the saturation magnetization (M_S) of the nanocomposites, surprisingly, the FC1 (composite with 1 % amine-functionalized MWCNT) and FC3 (composite with 3 % amine-functionalized MWCNT) nanocomposites exhibited higher saturation magnetization (M_S) compared to bare Fe₃O₄, attributed to the enhanced interaction between Fe₃O₄ and the amine-functionalized MWCNTs, which facilitated the cationic influx and alignment of surface spins. However, at higher concentrations of functionalized MWCNTs (FC7 and FC10), a reduction in M_S was observed, possibly due to aggregation effects which can also be inferred from their cubic anisotropy value. Among the nanocomposites, FC3 exhibited the highest specific absorption rate (SAR), correlating with its enhanced M_S, while FC10 showed the lowest SAR, consistent with its reduced M_S. The SAR values were found to increase with the applied magnetic field amplitude, with FC3 surpassing bare Fe₃O₄ at higher field amplitudes, likely due to the predominant effects of Néel relaxation mechanisms. The observed enhancement in magnetic properties at optimal MWCNT concentrations presents a promising pathway for the design of advanced magnetic nanocomposites with improved performance in hyperthermia applications.