Hydrogen Annealing Effect on the Magnetic Properties of ZnCoO/MoS2 Hybrid

Abstract

The ZnCoO/MoS2 hybrid is successfully synthesized through a general and facile process. High-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Raman spectra reveal that the hybrid consists of wurtzite ZnCoO and few layers of MoS2, which shows a paramagnetic property. In contrast, the hybrid presents clear magnetic hysteresis at room temperature with a H2 post-annealing process. No Co metal nanoclusters can be identified by XRD and HRTEM. The red shift of $ \mathrm{E}_{{2}\mathrm{g}}^{1} $ and A1g peak indicates the strain effect induced by H2 annealing. On the other hand, the disappeared peak at 477 cm−1 can be ascribed to the modification of the interface and surface state of the ZnCoO. Temperature-dependent Raman spectroscopies demonstrate the significant H2 annealing effect on the structural properties of ZnCoO/MoS2 hybrid. The interplay between the electron interaction at the interface and oxygen vacancies of ZnCoO can be responsible for the magnetic properties of the ZnCoO/MoS2 hybrid. The tunable magnetic properties have a promising application in multifunctional MoS2-based semiconductor and spintronic devices.