Robust Synthesis of Silver Nanocubes in Oil Phase
Jiahao Pan, Wei Wang, Min Ji, Xing Xing, Zhenda Lu
Abstract
Although various methods have been developed to synthesize Ag nanocubes, their synthesis in oil phase has received little attention. We report a robust method to synthesize single-crystalline Ag nanocubes with high purity (>95%) and uniform size in oil phase. The evolution of Ag nanoparticles from different reaction times indicates that multiply twinned seeds (MTDs) and single-crystalline seeds were formed together at the early stage of the reaction. With the reaction process, the MTDs were gradually etched by chloride ions and air, and the remaining single-crystalline seeds grew into nanocubes. The effect of synthetic parameters such as temperature, air flow, and the concentration of cupric chloride and AgNO 3 precursors on the morphology and size of Ag nanocubes has been systematically investigated, among which temperature plays an important role in controlling the balance between the etching rate and growth rate. Due to the slow ion diffusion rate compared to that in the water or polyol system, oil-phase synthesis provides a wide regulatory window for completely etching the MTDs, ensuring the high purity of single-crystalline Ag nanocubes.