Graphene　nanoflakes　(GNFs)　were　grown　on　silicon　substrates　pre-coated　with　different　thicknesses　of　zinc　oxide　(ZnO)　films　by　hot　filament　chemical　vapor　deposition　in　the　methane　environment.　The　structural,　compositional　and　photoluminescence　(PL)　properties　of　the　synthesized　GNFs　were　systematically　and　extensively　studied　using　a　broad　range　of　advanced　characterization　instruments　including　field　emission　scanning　electron　microscope,　high-resolution　transmission　electron　microscope,　Raman　spectroscopy,　and　X-ray　photoelectron　spectroscopy,　etc.　It　is　shown　that　the　GNFs　can　be　synthesized　on　ZnO　films　and　that　the　thickness　of　GNFs　reduces　with　the　increased　thickness　of　ZnO　films.　It　is　also　shown　that　the　GNFs　can　generate　a　series　of　strong　green　PL　bands,　but　the　green　PL　bands　shift　towards　long　wavelengths　with　the　increased　thickness　of　ZnO　films.　The　change　in　the　structural　and　PL　properties　of　GNFs　has　been　analyzed　in　terms　of　the　features　of　graphene　nanoribbons　and　the　interfacial　interaction　of　GLFs　with　ZnO　films.　These　outcomes　can　contribute　to　the　control　of　growth　and　structure　of　graphene-based　materials　and　the　fabrication　of　the　optoelectronic　devices　relevant　to　graphene-based　materials.　(C)　2016　Elsevier　B.V.　All　rights　reserved.