Kinetic engineering for the robust synthesis of Au nanocubes in cetylpyridinium chloride (CPC) system

Abstract

Au nanocubes have emerged as highly promising nanostructure because of their strong and tunable LSPR properties. However, the direct synthesis of Au nanocubes with improved corner sharpness and yield is still changeling. In this work, a robust synthesis strategy in cetylpyridinium chloride (CPC) system for Au nanocubes with high sharpness and yield is proposed without any purification process. Importantly, the synthesis of Au nanocubes is insensitive to the concentration of both ascorbic acid (AA) and Br^- ions under the CPC system, which is conducive to the repeatable and mass production of Au nanocubes. Moreover, the systematic deposition kinetics was demonstrated by changing the concentration of AA, Br^- ions and Au seeds. Interestingly, a novel nanocrystal of asymmetric bipyramid appeared as impurity in process of the CPC system-based Au nanocubes synthesis and its geometry features were analyzed comprehensively. As a result, our strategy opens an avenue for the reproducible and operable fabrication of Au nanocubes with scaling-up production.