Novel plasmonic photocatalysts were fabricated by the modification of 5 3D Bi 2 O 2 CO 3 microspheres with Au nanoparticles (NPs) via a facile one-pot in situ method for the first time. The as-obtained 3D Au/Bi 2 O 2 CO 3 heterostructures (Au/BOC) were characterized by XRD, XPS, SEM , TEM , EDX, N 2 adsorption-desorption isotherms, UV-vis DRS and PL. The results revealed that the Au NPs were produced from in situ reduction of Au 3+ by the citrate ions and 10 deposited on the surface of Bi 2 O 2 CO 3 microspheres. The photocatalytic activity of Au/BOC was evaluated by removal of NO under visible light with the pure Bi 2 O 2 CO 3 as reference. The pure Bi 2 O 2 CO 3 microspheres displayed decent photocatalytic activity due to the surface scattering and reflecting (SSR) resulted from the special hierarchical architecture. The Au/BOC exhibited highly enhanced 15visible light photocatalytic performance in comparison with the pure BOC because of the co-contribution of the SSR effect, the Schottky barrier and the surface plasmon resonance (SPR) effect endowed with metallic Au NPs. The integration of the SSR effect and SPR effect on one system for enhancing photocatalysis could provide a new scope in architecture design and mechanism understanding of other 20 noble metal-based plasmonic photocatalysts.