Tailoring electronic and optoelectronic properties of 2D-SiC defects and doping: a first-principles study toward efficient white light-emitting diodes.

The advent of graphene catalyzed extensive exploration into two-dimensional (2D) materials, owing to their extraordinary electronic, mechanical, and optical properties. Among these, two-dimensional silicon carbide (2D-SiC) has emerged as a compelling candidate for next-generation optoelectronic devices due to its inherent planar structure, robust mechanical strength, high exciton binding energy, high thermal stability, and wide band gap. In this work, we present a comprehensive first-principles investigation into the effects of intrinsic point defects including vacancies and antisites as well as substitutional doping with various single foreign atom (, As, Bi, Ga, Ge, In, P, Pb, Sb, Sn, Te, Ca, K, Mg) on the electronic and optical properties of 2D-SiC. Using density functional theory (DFT), we demonstrate that the direct band gap of pristine 2D-SiC is preserved in the presence of key defect types and dopants, affirming its suitability for efficient light-emitting applications. Building upon these findings, we propose a novel light-emitting diode (LED) architecture utilizing defect, doping-tailored 2D-SiC as the active emissive layer. Simulated optical and electrical performance metrics, including power spectral density, current-voltage characteristics, luminous power, light extraction efficiency, and CIE color coordinates, confirm the feasibility of achieving high-performance white light emission through strategic RGB color mixing. These findings confirm the capabilities of defect and dopant-engineered 2D-SiC as a high-performance material platform for adjustable light emission within the visible spectrum, which highlights its appropriateness for incorporation into cutting-edge optoelectronic devices and solid-state lighting applications.