Single-step synthesis of hierarchical flower-like silver structures with assistance of gallic acid

We synthesize hierarchical flower-like silver microspheres with tunable size and shape, using ascorbic acid as reducing agent and gallic acid as structure-directing agent. The chemical nature of the gallic acid plays a vital role in the process of assembling silver particles into Chinese rose hierarchical structures. By changing the amount of gallic acid or silver nitrate solution (AgNO 3 ), it is easy to adjust the anisotropic morphologies of as-synthesized silver structures and promote the preferential growth, resulting in a complete, clear, and stable multi-layered floral silver structure. This single-step wet-chemical synthesis method provides a new synthetic strategy for the anisotropic growth and morphology control of flower-like silver particles.