Hydrogenation effect on magnetic single domains of high-temperature-deposited uniform Co_xPd_1−x/MoS₂ flakes

In this study, 6-nm Co_xPd_1−x alloy films were deposited on MoS₂ flakes at a high temperature (HT) of 200 °C. The morphology and magnetic properties of these flakes was studied. In contrast to the nanoparticle assembly fabricated through room-temperature deposition, HT growth led to a relatively uniform coverage on MoS₂ flakes with a roughness of less than 1 nm. The flat Co_xPd_1−x alloy films form magnetic single domains on individual MoS₂ flakes. For 6-nm Co_0.5Pd_0.5 and Co_0.35Pd_0.65, the magnetic coercivity (H_c) was approximately 50 Oe. Co_0.5Pd_0.5/MoS₂ exhibited more distinct azimuthal angle-dependent magnetic behavior than that of Co_0.35Pd_0.65/MoS₂. The different angle-dependent H_c variation for various MoS₂ flakes could be attributed to the shape and demagnetization effect at the edge. After hydrogen exposure, the H_c of Co_0.5Pd_0.5/MoS₂ was enhanced by 30% ± 10% and the magnetic domains extended over the MoS₂ flakes, which indicated that H absorption in Co_0.5Pd_0.5 bridges magnetic coupling across the MoS₂ edge.