The　plasmonic　AgCu-decorated　TiO2　nanoring/nanotube　arrays　photoanode　was　synthesized　by　using　two-step　anodization,　and　the　effect　of　bimetallc　AgCu　on　the　photoelectrochemical　response　of　TiO2　and　the　interface　properties　were　obtained　by　comparing　with　monometallic　Ag,　Cu　decorated　TiO2.　With　greater　visible　light　absorption,　longer　carriers’　lifetime　and　stronger　chemical　stability,　AgCu-TiO2　photoanode　shows　the　photocurrent　density　of　0.76　mA　cm−2　and　stable　H2　production　rate　of　376　µL·h−1·cm−2.　Thereafter,　the　electrostatic　properties　of　the　AgCu-TiO2/H2O,　Ag-TiO2/H2O　and　Cu-TiO2/H2O　systems　were　simulated　by　using　molecular　dynamics　simulations.　It　is　found　that　the　bimetallic　AgCu-TiO2/H2O　system　has　a　wider　depletion　layer,　which　helps　to　the　separation　and　transfer　of　photogenerated　electrons　and　holes.　Based　on　the　thermodynamic　and　kinetic　analyses,　the　carriers’　transport　pathways　were　obtained.　©　2023　Science　Press.　All　rights　reserved.