Molybdenum　selenide　nanomaterials　with　different　structures　are　synthesized　on　silicon　substrates　coated　with　gold　films　by　hot　filament　chemical　vapor　deposition　(HFCVD)　in　nitrogen　environment,　where　molybdenum　trioxide　and　selenium　powders　are　used　as　source　materials.　The　structure　and　composition　of　the　synthesized　molybdenum　selenide　nanomaterials　are　studied　using　field　emission　scanning　electron　microscopy,　transmission　electron　microscopy,　micro-Raman　spectroscopy　and　X-ray　photoelectron　spectroscopy.　The　results　indicate　that　the　structures　of　molybdenum　selenide　change　from　nanoflakes　to　nanoparticles　with　the　increase　of　content　of　molybdenum　trioxide　precursor.　The　photoluminescence　(PL)　excitation　using　the　325　nm　line　of　He-Cd　laser　as　the　excitation　source　generates　green　light　with　the　wavelength　of　about　512-516　nm.　The　formation　of　molybdenum　selenide　nanomaterials　is　determined　by　the　decomposition　rates　of　molybdenum　trioxide　in　HFCVD.　The　possible　factors　that　affect　the　generation　of　green　PL　bands　are　analyzed.　These　outcomes　of　this　work　enrich　our　knowledge　on　the　synthesis　of　transition　metal　dichalcogenides　and　contribute　to　the　development　of　applications　of　these　materials　in　optoelectronic　devices.　(C)　2015　Elsevier　B.V.　All　rights　reserved.