Synthesis of Ag microparticles with hierarchical nanostructure on the anode of a galvanic cell

In this work, three-dimensional (3D) hierarchical silver microparticles (HSMP) composed of 2D nanoflakes were synthesized on the anode of a galvanic cell. A copper plate immersed in CuSO4 solution and a platinum-coated silicon plate immersed in AgNO3 solution served as the cathode and anode, respectively. The two half-cells were linked by a salt bridge. The presence of poly(N-vinyl pyrrolidone) (PVP) in the AgNO3 electrolyte, an optimum AgNO3 concentration and an appropriate reaction time are crucial for the formation of a hierarchical nanostructure. The evolution of the products during growth was tracked to study the formation and metamorphosis mechanisms. The catalytic activity of HSMP was studied via promotion of Rhodamine B reduction by NaBH4.