Scheme 1. Schematic of the Bottom-up Chemical Engineering of Inorganic Nanosolids by Assembly and Consolidation of NPs.

Heterostructured NRs with identical material A at the tips but with long (top) and short (middle) segments of material B in between allow for uniform distribution of the material A in the matrix of B. Such a strategy is presented in this study using colloidal heteronanorods that combine Ag₂S (material A tips) with PbS (material B, rods). In contrast, mixing two separate colloids of materials A and B commonly leads to partial phase-segregation that is hard to predict and control (bottom image).