Plasmon-Driven Reconfiguration of Metal Nanoparticle Defect Structure

We report a visible light-driven approach for converting planar-twinned Ag triangular prisms into multiply twinned Ag icosahedra. To our knowledge, this is the first demonstration of a post-synthetic reconfiguration of nanoparticle twin structure using light and it is one of the only post-synthetic methods for reconfiguring nanoparticles with one defect structure into another. Crystalline defect structure influences catalytic reactivity and selectivity, and thus the ability to reconfigure defect structure provides a promising handle for tuning catalyst performance. In addition, we have developed a method for further reconfiguring the defect structure of these multiply twinned Ag icosahedra back to planar-twinned Ag prisms through subsequent light-induced steps and pH control. To do so, we first determined the mechanism of the initial Ag prism to Ag icosahedra conversion and then used insight from that mechanism to overcome challenges in further material transformations. This interconversion of Ag nanoparticle shape and defect structure between prisms, icosahedra, and spheres using visible light opens opportunities for the reuse and recycling of Ag nanomaterials and provides a pathway to the synthesis of shape-reconfigurable nanocatalysts with light-tunable reactivity.