Cover story: Wang YD, Wang YW, Dong YL, Zhou L, Kang JL et al. 2D Nb₂CT_x MXene/MoS₂ heterostructure construction for nonlinear optical absorption modulation. Opto-Electron Adv 6, 220162 (2023).

Two-dimensional (2D) materials possess distinctive and adjustable optical, chemical, and electronic characteristics. Due to their remarkable and diverse light-matter interactions, they have garnered significant attention in the fields of optoelectronics and photonics. However, the current knowledge of their photophysical properties and techniques to enhance their optical performance remains limited. To address this issue, the researchers feature an exciting research that demonstrates how to modulate both linear and nonlinear optical properties of two-dimensional (2D) materials. They achieved this by synthesizing a 2D Nb₂C/MoS₂ heterostructure, where MoS₂ nanocrystals were in-situ grown on Nb₂C nanosheets. This heterostructure exhibited superior optical absorption and modulation capabilities compared to pristine Nb₂C, over a broad wavelength range. The charge transfer occurring at the interface may contribute to the observed linear and nonlinear absorption modulation. This research introduces an effective method for regulating the nonlinear optical response of MXenes and other 2D materials by constructing heterostructures.