Numerical investigation of surface roughness effects on Ti <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si5.svg" display="inline" id="d1e301"> <mml:msub> <mml:mrow/> <mml:mrow> <mml:mn>3</mml:mn> </mml:mrow> </mml:msub> </mml:math

MXenes are a newly discovered class of materials with outstanding potential properties for usage in next-generation electromagnetic absorbers. Although the morphology of MXene has a significant impact on absorption characteristics in experiments, there is still a lack of numerical research on it. Herein, a simple Air–MXene (Ti 3 C 2 T x ) structure with a rough surface, defined by a sum of different spatial frequencies, is proposed and analyzed numerically. The effectiveness of the numerical model is validated by reconstructing the profile of real MXene’s rough surface. Introducing proper roughness to MXene’s surface can effectively enhance its absorption across ultraviolet to infrared wavelengths. High spatial frequency and its amplitude, corresponding to small-scale structures, can boost absorption significantly in the shortwave range. When these small-scale structures have sufficient amplitude, they can enable perfect absorption ( > 99%) from the ultraviolet to the visible region. With a further increase in the entire surface structure’s amplitude, perfect absorption can be extended to the infrared region. These studies in constructing MXene rough surface structures and conducting numerical analysis offer critical perspectives on bridging morphology reality and optical design, allowing MXenes to unlock their full potential in photonics. • Propose surface roughness effect on the absorption of MXene numerically. • Introducing proper roughness can effectively enhance the absorption of MXene. • High spatial frequency can boost absorption significantly in the shortwave range.