In order to pursue the interface effect on the band offset of the semiconductor nanocrystals with the type-I core-shell structure, we have established a theoretical model to elucidate the underlying mechanism based on the atomic-bond-relaxation consideration and continuum mechanics. It was found that the size-dependent interface bond-nature-factor of the core-shell nanocrystals can be deduced on the basis of the proposed model. Taking the typical CdSe-ZnSe nanostructure as an example, we showed that the theoretical results were consistent with the experimental observations. These investigations provided a useful guide in opening up the possibility to engineer nanodevices with special optoelectronic properties.
