Tunable visible-light response of strained carbon-doped MoS2 monolayers for prospective color-vision-correction filters

Selective modulation of visible light is central to optical strategies for color vision correction. Here, we use first-principles density functional theory calculations to examine how substitutional carbon incorporation and biaxial strain modify the optoelectronic response of MoS 2 monolayers. Carbon substitution at sulfur sites substantially reconstructs the electronic band structure and strongly reduces the band gap. Among the investigated compositions, MoS 1.67 C 0.33 displays a distinct absorption feature fully within the visible range ( – nm). We therefore analyze this composition under in-plane biaxial strain and show that mechanical deformation systematically tunes the absorption intensity in selected visible-wavelength windows. These results indicate that combined chemical substitution and strain engineering provide an effective materials-level route for tailoring the visible-light response of carbon-doped MoS 2 monolayers. The findings also provide a theoretical basis for future wavelength-selective ultrathin filters designed for prospective color-vision-correction technologies.