Covalently Silane-Functionalized Antimonene Nanosheets and Their Copolymerized Gel Glasses for Broadband Vis–NIR Optical Limiting

Two-dimensional antimonene has many potential applications for its high mobility, high stability, and tunable band gap. The covalent chemistry of antimonene and the molecular doping or hybrid of antimonene remain incomplete for further applications. In this work, silane-functionalized antimonene nanosheets and their copolymerized organically modified silicate gel glasses are designed and prepared. The experimental data confirmed that 3-glycidoxypropyltrimethoxysilane interacts covalently with antimonene. Compared with unfunctionalized antimonene, the silane-functionalized antimonene shows higher concentration, higher compatibility, and dispersion stability in solvents and gel matrices. In particular, the doping concentration of functionalized antimonene nanosheets can reach 2% in gel glass, which is larger than conventional nanocomposites and nanohybrids. These nanosheets exhibit outstanding optical limiting performance in the visible and long-wavelength near-infrared regions (532–2150 nm). The mechanism of optical limiting is found to be a combination of nonlinear absorption, nonlinear refraction, and nonlinear scattering. The silane-functionalized antimonene nanosheets and their copolymerized hybrids will be promising materials for optoelectronics, biology, energy, and others.