Encapsulation of graphene oxide/metal hybrids in nanostructured sol–gel silica ORMOSIL matrices and its applications in optical limiting

•GO/metal NP hybrids were incorporated into ORMOSIL gel glasses successfully.•GO/metal NP changed the surface characteristics of silica-based gel glasses.•The hybrids exhibited significantly enhanced OL performance in ORMOSIL gel glasses.•The OL mechanisms of hybrids in gel glasses were attributed to ESA and NLS.

Optically transparent organically modified silica (ORMOSIL) gel glasses doped with graphene oxide (GO)/metal nanoparticle (NP) hybrids were synthesized using a simple sol–gel technique. The two-dimensional GO/metal NP hybrids dramatically changed the surface characteristics of silica-based gel glasses whilst maintaining their structural integrity during the sol–gel procedure. The optical limiting (OL) properties of GO/metal NP-doped ORMOSIL gel glasses were investigated using a nanosecond open-aperture Z-scan technique at 532 nm. The metal NP hybrids exhibited significantly enhanced OL performance compared with their individual counterparts in ORMOSIL gel glasses. The improvement in GO/Au NP-doped gel glasses is attributed to surface plasmon resonance, while interband transition is responsible for the enhancement in GO/Pd NP-doped gel glasses. The OL behavior of GO/metal NP-doped gel glasses were mostly attributed to the combined mechanisms of excited state absorption and nonlinear scattering.