Interface engineering of modified ZnO@MoS2 heterostructure to efficiently enhance charge transfers and carrier regulation

The metal oxide combined with transition metal dichalcogenides (TMDs) was used to regulate the absorption band range and nonlinear transmittance for TMDs base materials. The interfacial charge transfers and carrier regulation of ZnO and TMDs are very important for the novel two-dimensional semiconductor optoelectronic device technology in the future. Herein, the synthesis, properties and applications of ZnO and MoS2 composites are reviewed. The syntheses of modified ZnO@MoS2 heterostructure by the two-step hydrothermal were reported for the first time. The growth and electron transfer mechanisms of heterostructure were systematically studied. The surface of the ZnO@MoS2 heterostructure can be confirmed by scanning electron microscopy, which is self-assembled into nanoflowers from MoS2 nanosheets. The X-ray diffractometer (XRD) and Raman spectra of ZnO@MoS2 heterostructure were measured, and it was confirmed that ZnO can promote the accumulation of MoS2 nanosheets. The flower-like MoS2 nanosheets were “planted” on the surface of ZnO nanorods, attributing to the two growth orientations of MoS2 in C-axis C// and C⊥. Based on the linear optical behavior of the samples in the UV–Vis bands, the position and effective state density of defect state can be estimated qualitatively. The above behavior is beneficial to understand the band gap narrowing of MoS2 and the effect of ZnO nanorods on the photoelectric properties of MoS2 was studied in detail. In addition, type-I band alignment was established at the interface between ZnO nanorods and MoS2 nanosheets, which increase electron-hole pairs separation of modified ZnO@MoS2 heterostructure. The modified ZnO@MoS2 heterostructure with controllable photoelectric structure display excellent photoelectric characteristics, which are desirable for field of nonlinear optics, photoelectric functional devices, energy environment and other fields.