Anisotropic and Multicomponent Nanostructures by Controlled Symmetry Breaking of Metal Halide Intermediates

We propose and validate herein a solution-phase synthetic strategy relying on in situ photostimulation and reduction of metal-halide intermediates to yield complex anisotropic and multicomponent nanostructures. Exposure of AgBr nanoparticles to ultraviolet light and l-Arginine forms dimers composed of crystalline Ag and AgBr nanophases. The Ag nanoparticle nucleates at and grows from a single point on the surface of the AgBr phase and the interface connecting these phases is atomically sharp. The complex nanostructures are generated at greater than 80% yield and are highly monodisperse in morphology and in size. The high crystallinity of the nanophases arises from an apparent solid–solid crystallization process and is unusual considering the nearly 40% lattice mismatch between Ag and AgBr. Such structures may be used to interrogate photocatalytic mechanisms or to construct more complex materials.