摘要： 2D heterojunction based on g-C3N4 nanosheets with other semiconductor nanosheets is a promising way to improve photocatalytic hydrogen evolution (PHE) activity over g-C3N4. However, current 2D heterojunction based on g-C3N4 are unsatisfactory due to their insu?cient absorption of visible light and ine?cient charge separation. In this work, Ag/TiO2/g-C3N4 nanocomposites based on 2D heterojunction coupling with Ag surface plasmon resonance (SPR) were synthesized by a method combining facile wetness impregnation calcination. The PHE activity of Ag/TiO2/g-C3N4 nanocomposites is attributed to the TiO2/g-C3N4 2D heterojunction and bare g-C3N4 nanosheet under visible light irradiation, indicating a cooperative e?ect between Ag and TiO2/g-C3N4 2D heterojunction. As a result of SPR e?ect, the composites strongly absorb visible light. In addition, the oscillating hot electrons from Ag can easily transfer to 2D heterojunction. This synergistic e?ect lead to su?cient visible light absorption and e?cient charge separation of 2D heterojunction, which improved the PHE activity of g-C3N4. This work indicates that loading metal nanoparticles on 2D heterojunction as metal SPR-2D heterojunction nanocomposites may be a potential method for harvesting visible light for PHE.