▎ 摘　　要

The superior structural, optical, and electrical characteristics of the core-shell structure make it a potential issue in optoelectronic devices. High-performance photovoltaic devices with core-shell structures can be obtained by optimizing the preparation conditions. This work describes the use of laser ablation in liquid to fabricate graphene oxide@ZrO2/p-Si heterojunction photodetectors. The effect of the application of an external magnetic field ( M-field) on the properties of the graphene oxide@ZrO2 core/shell was investigated. Nd:YAG laser pulses with a wavelength of 1.064 mu m and a laser fluence of 4.3 J/cm(2) were used for ablation of graphene oxide (GO) nanosheets and ZrO2 nanoparticles in water, respectively, as the core and shell. The structural characteristics of the synthesized core-shell confirmed the formation of monoclinic ZrO2 and the crystallinity of the core-shell is improved when an applied magnetic field is used during the laser ablation. The optical energy gap of graphene oxide@ZrO2 nanoparticles increased from 4 to 4.6 eV when the magnetic field is applied. The morphology of the product reveals the formation of a core/shell. The agglomeration and aggregation of the particles are reduced after applying an external magnetic field. A high-performance visible enhanced graphene oxide @ZrO2/Si photodetector is fabricated and characterized. The photodetector parameters were considerably enhanced when the magnetic field was applied. Application of the magnetic field leads to an increase in the responsivity of the photodetector from 0.58 to 0.78 A/W at 560 nm.Detectivity as high as of 4 x 10(11) Jones and external quantum efficiency near 100% at 560 nm are obtained. The energy band lineup of the graphene oxide@ZrO2/Si heterojunction is constructed and discussed. Based on the obtained results, the photodetectors fabricated by this route can be used efficiently in detection of weak optical signals.