Hierarchically Organized Chiral Supraparticles of Twisted Gold-Cysteine Sheets

The structural complexity of composite biomaterials and mineralized particles arises from hierarchical ordering of inorganic building blocks over multiple scales. While empirical observations of complex structures from nanoparticles are abundant, assembly mechanisms leading to their geometrical complexity are still puzzling especially for non-uniformly sized components. Here, we report the assembly of hierarchically organized particles (HOPs) with twisted spikes and other morphologies from polydispersed Au-Cys nanoplatelets. Complexity of HOPs is comparable to biological counterparts as enumerated by graph theory methods. Their intricate hierarchical organization emerges from competing electrostatic and elastic restrictions that render assembly pathways primarily dependent on nanoparticle symmetry rather than size. Upon varying the enantiomeric excess and synthesis temperature, a large family of colloids with complex architectures and unusual chiroptical and chemical properties are explored.