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It is challenging to find a conventional nanofabrication technique that can consistently produce soft polymeric matter of high surface area and nanoscale morphology in a way that is scalable, versatile, and easily tunable. Here, the capabilities of a universal method for fabricating diverse nano- and micro-scale morphologies based on polymer precipitation templated by the fluid streamlines in multiphasic flow are explored. It is shown that while the procedure is operationally simple, various combinations of its intertwined mechanisms can controllably and reproducibly lead to the formation of an extraordinary wide range of colloidal morphologies. By systematically investigating the process conditions, 12 distinct classes of polymer micro- and nano-structures including particles, rods, ribbons, nanosheets, and soft dendritic colloids (dendricolloids) are identified. The outcomes are interpreted by delineating the physical processes into three stages: hydrodynamic shear, capillary and mechanical breakup, and polymer precipitation rate. The insights into the underlying fundamental mechanisms provide guidance toward developing a versatile and scalable nanofabrication platform. It is verified that the liquid shear-based technique is versatile and works well with many chemically diverse polymers and biopolymers, showing potential as a universal tool for simple and scalable nanofabrication of many morphologically distinct soft matter classes.

A simple process for batch or continuous formation of polymer nanofibers and other nanomaterials in the bulk of a sheared fluid medium is introduced. The process may be of high value to commercial nanotechnology, as it can be easily scaled up to the fabrication of staple nanofibers at rates that may exceed tens of kilograms per hour.

and strategies for the assembly of particle structures classified on the basis of their dimensionality. We survey the potential areas of application of the structures assembled from particles, and discuss why the technological potential of these structures is at present largely unrealized. Many of the challenges in the area of nanocolloidal assembly relate to the development of assembly processes that are scalable, controllable, rapid, and inexpensive. The power and versatility of colloidal-particle assemblies are best illustrated by the vast number of structures and strategies for their fabrication reported in the literature. A convenient way to classify the majority of the colloidal assemblies could be based on their dimensionality and degree of ordering ‐ three, two, one-dimensional, or independent clusters. In order to evaluate the ease and precision of the controlled fabrication of such materials, we also need to analyze in each case the physical principles by which a certain structure is assembled. The assembly can be accomplished by an extensive array of techniques based on numerous physical mechanisms. A survey of a few major groups of methods that have found use in the controlled assembly of particles into materials with well-organized and defined microstructures is presented in Table 1. The goal of these techniques is to collect the particles

The formation of nanostructured materials by using colloidal crystals as templates is a relatively new but rapidly growing area of materials science. Colloid crystalline templates are three-dimensional close-packed crystals of submicrometer spheres, whose long-ranged ordered structure is replicated in a solid matrix, to yield materials with ordered pores. These materials hold promise for use as photonic crystals, advanced catalysts, and in a variety of other applications. Here we review the wide range of materials that have been made following the original synthesis of structured porous silica. This method has been recently modified to produce porous metals.