The density functional theory (DFT) was used to analyze the electron spin competition interaction between next neighbor Ni atoms in various artificially designed structures in a nano-SiC monolayer honeycomb structure. The electronic structural, magnetic and optical properties of a monolayer SiC materials that were doped with different quantities of Ni in a specific shape are detailed in this paper. Interestingly, spin polarization appeared to occur in the structures that were doped with one Ni and 3Ni having a triangular structure. However, there was no spin polarization present in these materials prior to Ni doping, 2Ni doping with a linear structure and 4Ni doping with rhombic structure. The conduction band of the Ni-doped system moved toward the low energy direction which produced a decrease in the band gap. Calculations of the optical properties showed that Ni doping enhanced their photoconduction. It is hoped that the results of this study will have encouraging implications for the application of photoelectric devices and controllable magnetic materials.