Tuning the Shape of Gold-Silver Nanocrystals by Separately Controlling the Metal-Atom Concentration in a One-Pot Synthesis

摘要

We report a niche synthetic strategy to manipulate the shape of gold-silver(AuAg)nanocrystals based on kinetics control.The success of current work relies on the use of two syringe pumps to add Au and Ag precursor solutions independently at distinct injection rates,which allows the separate control over the feeding rate of Au and Ag atoms,respectively.Such strategy is validated effective in both one-pot reduction and seeded growth involving spherical and rod-likes Au seeds.By conducting orthogonal experiments setting two injection rates at three levels,a set of morphologies are obtained.Interestingly,AuAg alloy nanocrystals in the form of multipod,hollow protruded particles,and branched hollow nanoplate,that are rare to obtain via conventional routes,are successfully screened out,exhibiting the unique advantage of this strategy.The current work provides a feasible approach to applying kinetics control over AuAg bimetallic nanocrystals,which could be extended to other noble metals or material combinations.