The present invention provides compositions (“Optical Nanomaterial Compositions”) comprising one or more nano-materials and an optical coupling gel or an optical adhesive. The invention also provides methods for using the Optical Nanomaterial Compositions as an index-matching gel, an optical adhesive or an optical film, all of which are suitable for optical and sensing de-vices applications, including but not limited to noise suppression, passive Q-switching, mode-locking, waveform shaping, optical switching, optical signal regeneration, phase conjugation, in filter devices, dispersion compensation, wavelength conversion, soliton stabilization, microcavity applications, in interferometers (such as the Gires-Tournois interferometer), optical, magneto-optical or electro-optical modulation, biochemical sensors and photodetectors.