▎ 摘　　要

Silicon/graphene nanocomposites (Si/GNCs) are one of the promising candidates for the increasing demands of portable electronic devices and electric vehicle applications. However, two-dimensional (2D) Si phase component in Si/GNCs was rarely reported. In this work, we present the preparation of Si/nitrogen-doped graphene composite nanosheets (Si/NDGCNSs) by DC arc discharge under nitrogen of 800 degrees C, using an anode with comparatively high Si content and good homogeneity. 2D Si nanostructures were observed in the Si/NDGCNSs. The phase composition of the Si/NDGCNSs includes graphitic carbon, Si and silicon carbide (SiC). The suspensions of the Si/NDGCNSs in distilled water and ethanol were stable for more than one and two months respectively, and both of them emitted green luminescence under irradiation of UV light. Their UV-vis spectra show two absorption peaks. The formation mechanism of the Si/NDGCNSs is discussed briefly. The as-prepared Si/NDGCNSs may be used for photocatalysts, solar cells and energy storage devices, etc.