We　report　the　large-scale　synthesis　of　monodisperse　Ag　nanoparticles　and　their　homogeneous　assembly　into　TiO2　nanotube　arrays　(TNAs)　for　enhancing　the　visible-light　photoelectrocatalytic　(PEC)　activity　of　the　photoanodes.　Electron　beam　irradiation　reduction　was　used　to　synthesize　monodisperse　mesoporous　Ag　nanoparticles,　composed　of　smaller　nanocrystals,　with　the　aid　of　PVP　surfactant.　Ag　nanoparticles　exhibit　an　absorption　band　centered　at　410　nm,　originating　from　localized　surface　plasmon　resonance　(LSPR).　To　explore　LSPR　effects　on　the　visible-light　PEC　performance　of　TNAs,　we　prepared　defect-sensitized　TNAs　by　anodic　oxidization,　followed　by　a　poor-oxygen　annealing　treatment　to　induce　a　wide　range　of　visible-light　response　owing　to　the　incorporation　of　Ti3+　defects.　A　vacuum-assisted　filling　method　was　used　to　assemble　Ag　nanoparticles　into　the　defect-sensitized　TNAs.　Compared　with　unfilled　TNAs,　a　2.5-fold　enhancement　in　the　visible-light　PEC　activity　was　observed　in　the　composite　photoanodes,　which　is　attributed　to　LSPR-induced　absorption　enhancement　in　a　wavelength　range　of　400-450　nm,　as　well　as　to　the　effective　suppression　of　the　recombination　of　photoexcited　electrons　and　holes　through　the　Ag-TiO2　Shockley　junction.　(C)　2013　Elsevier　B.V.　All　rights　reserved.