Experimental and theoretical investigation of nanodiamond insertion on the interlayer interaction in multilayer stacking graphene

Multilayer stacked graphene (Gr) exhibits a wider range of novel properties than monolayer Gr, and it can be further applied to larger scales. Moreover, by modulating the interlayer structure and interactions, we can move beyond the energetically favorable AB stacking and explore unprecedented phenomena. In this study, nanodiamonds (ND) were introduced as nanospacers to manipulate the microstructure of multilayer Gr stacking. The presence of nanospacers increases the interlayer spacing and reduces interlayer interaction, which retrieves the linear band structure. The Gr and ND (Gr–ND) stacking structure was fabricated experimentally using a layer-by-layer transfer method. Raman spectroscopy confirms a decrease in interlayer interaction within the stacking structure, and atomic force microscopy reveals an expansion of the interlayer distance, contributing to the weakening of interlayer interactions. Theoretical analysis was conducted by combining molecular dynamic simulation and a continuum model to understand the experimentally observed change in microstructure caused by ND insertion. The ND density and size determine the interlayer distance, indicating the preference for configuration with lower system energy. The guideline for forming Gr–ND stacking structures obtained in this study can contribute to the property modulation and application of multilayer stacked Gr.