Patchy nanoparticles with surface complexity for directed self-assembly

Patchy nanoparticles (PNPs) possess anisotropic surfaces that produce emergent directionalities in interactions. Manipulation of such surface complexities offers a powerful handle for control over interparticle spatial and orientational orderings, making PNPs an ideal class of nanoscale synthons for self-assembly. However, realization of PNPs with defined patch positions and geometries faces technical challenges related to the level of precision chemistry required to achieve the desired surface patterning. Here, we provide an in-depth review of state-of-the-art strategies available for PNP synthesis. We examine the experimental efforts made to synthesize PNPs, classifying advances based on different material types spanning organic and inorganic systems. We conclude by presenting barriers in PNP synthesis and highlighting ongoing theoretical efforts aimed at guiding experimental design and parameter selection for creating novel surface patterning on NPs.