Self-Assembly and Formation of Hierarchically Structured Nanocrystals with Photocatalytic Activity

Design and engineering of the size, shape, and chemistry of photoactive building blocks enable fabrication of functional nanocrystals for applications in light harvesting, photocatalytic synthesis, and water splitting. Here we report the synthesis of such nanocrystals through a surfactant-assisted self-assembly process using optically active porphyrin as a functional building block. The self-assembly process relies on specific interactions such as π–π stacking and ligand coordination between porphyrin building blocks. The nanocrystals exhibit well-defined 1-3D morphologies and hierarchically ordered internal architectures. At the molecular level, porphyrins with well-defined size and chemistry possess unique optical and photocatalytic properties. On the nanoscale, controlled assembly of porphyrins leads to formation of ordered nanostructures with precisely defined size, shape, and spatial monomer arrangement to facilitate intermolecular charge and energy transfer.
Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.