▎ 摘　　要

NOVELTY - Photoluminescence wavelength tunable material comprises a composite comprising metal nanoparticles attached to graphene oxide to vary light emission characteristics of graphene oxide. USE - The photoluminescence wavelength tunable material is useful in an optical device such as a solar cell (all claimed), an LED and an electroluminescence apparatus. ADVANTAGE - The photoluminescence wavelength tunable material increases the energy efficiency of the solar cell with reduced loss. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) an optical device comprising the photoluminescence wavelength tunable material; and (2) manufacturing the photoluminescence wavelength tunable material comprising forming a graphene oxide layer having a light emitting property, attaching the metal nanoparticles to the graphene oxide layer for changing the light emitting characteristic of the oxide, forming a composite comprising the metal nanoparticles, and mixing the metal nanoparticles with metal oxide nanoparticles.