Harnessing High Magnetic Anisotropy in Graphene Oxide-Based Nanocomposites: Implications for Designing Low-Cost Spintronics

Advancing spintronic and quantum technologies requires the enhancement of magnetic properties in graphene-based materials. In this work, we systematically engineer graphene oxide (GO)-based nanocomposites to induce ferrimagnetism, enhance magnetization at elevated temperatures, and significantly improve magnetic anisotropy. Notably, an exceptionally high magnetic anisotropy (up to 1.06 × 10 6 erg cm –3 ) is achieved with low coercivity, even at a low Fe concentration (10 wt %), representing a rare combination not widely reported. This enhancement originates from the synergistic interplay between the two-dimensional GO framework, defect-rich ZnO, and Fe-induced magnetic interactions, which collectively generate uncompensated and disordered surface and core spins via defect modulation. A direct comparison reveals a ∼ 9-fold increase in anisotropy for GZF-5 relative to ZnO@5Fe, highlighting the critical role of GO in tuning magnetic behavior. Density functional theory (DFT) calculations further confirm that GO functional groups and interfacial hybridization significantly modulate spin–orbit coupling and magnetic anisotropy. These findings demonstrate that defect engineering and interfacial design are as crucial as compositional tuning. The observed combination of high anisotropy, moderate magnetization, and near-room-temperature ferrimagnetism positions these nanocomposites as promising candidates for low-cost spintronic and magnetic memory devices.