Two-dimensional materials are among the most efficient optical materials for Q-switched pulse applications, rising to unprecedented heights. Although the exploration of 2D nanomaterials has attracted strong interest, the results from current studies remain questionable, requiring further achievements in tailored control of their properties. In this work, antimony sulfide (Sb2S3) nanosheets are prepared by liquid-phase exfoliation, and nanosheets of different sizes are obtained by regulating ultrasonication parameters and centrifugation speed. The nonlinear optical properties of Sb2S3 nanosheets are investigated using the Z-scan technique for the first time, which exhibit excellent saturable absorption and thereby promising potential for saturable absorber applications. Among the different sizes of Sb2S3 nanosheets, the smaller-sized nanosheets exhibit better nonlinear optical properties, which is ascribed to the higher proportion of surfaces and edges. Finally, stable laser pulses with peak power as high as 2.68 W are readily generated at the wavelength of 1064 nm. This work opens an innovative avenue toward nonlinear optical devices based on Sb2S3 and provides reasonable regulation of 2D saturable absorbers.

The continuous white‐light emission of carbon dots (CDs) can be applied to producing multicolor laser emissions by one single medium. Meanwhile, the solid‐state emission greatly contributes to its practical application. In this work, a strategy to realize the in‐situ hybridization of silane‐functionalized CDs (SiCDs) and 1,3,5‐benzenetricarboxylic acid trimethyl ester (Et3BTC) by a one‐pot solvothermal method is reported. Significantly, the SiCDs/Et3BTC hybrid crystals exhibit ultra‐broadband random laser emission over the near ultraviolet‐visible region under 265 nm nanosecond pulsed laser excitation. The wavelength region of laser emission is achieved from 315 to 600 nm within an emission band of CDs‐based materials. It is worth noting that the wavelength range of the laser is wider than the previously reported works. It is proposed that the continuous white‐light emission of SiCDs caused by multiple fluorescence centers mainly gives rise to the broadband random laser emission. Moreover, the crystals are conducive to forming resonance and realizing solid‐state laser emission. This in‐situ method is expected to enable a more convenient, cheaper, and greener approach to prepare luminescent hybrids for application in multicolor laser displays, multi‐level laser anti‐counterfeiting, supercontinuum light sources, and so on.

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