Influence of doping level on the structure, texture, and nonlinear optical properties of graphene oxide/Au hybrids doped ORMOSIL gel glasses

摘要

Graphene oxide (GO)/Au nanoparticle (NP) hybrids were introduced into nanostructured sol-gel organically modified silica (ORMOSIL) using a sol-gel technique. Scanning electron microscopy, Raman spectroscopy, thermogravimetric analysis, pore structure measurements, and UV-vis spectroscopy were performed to investigate the morphology, structure, texture, thermal stability and linear optical properties of the ORMOSIL gel glasses. The guest two-dimensional GO/Au NP hybrids maintained their own structures during the sol-gel procedure, confirming that the sol-gel technique can effectively produce graphene-based solid-state bulky composites. Increasing doping level would result in the formation of a highly porous structure, better thermal stability, and lower linear transmittance. The nonlinear optical (NLO) properties of GO/metal NP-doped ORMOSIL gel glasses were investigated using a nanosecond open-aperture Z-scan technique at 532 nm. The nonlinear absorption coefficient of GO/Au NP-doped ORMOSIL gel glasses increases from 3.79 cm/GW to 8.79 cm/GW with increased doping level from 4.8 × 10~(-3) to 19.2 × 10~(-3). The result demonstrates that the NLO performance of the composite ORMOSIL gel glasses can be optimized by tuning the doping level of 2D GO/Au NP sheet in the matrices of the host gel glasses. The NLO behavior of GO/Au NP-doped ORMOSIL gel glasses were attributed to the combination of nonlinear absorption and nonlinear scattering.