The need for scalable processes to produce structured materials on fine scales is well documented. Currently, methods for nanoscale particle production are typically constrained to specific material systems, simple particle architectures, and are applicable over narrow dimensional ranges; these limitations are dictated by process chemistry, growth kinetics, and the omnipresent effects of coarsening and agglomeration. Here we propose to harness a newly discovered nonlinear fiber fluid instability to generate regularly sized nanospheres in an approach that is at once both universal and scalable, age-old yet radically new.
The essence of our process is deceptively simple: We begin with an axially invariant fiber made of multiple materials. Fluid dynamic instabilities are thermally induced in a controllable manner in cylindrical domains internal to the fiber structure. The resulting spheres are generated with an unprecedented level of control over size, architecture, materials composition, and functionality. Moreover the linearly arranged, necklaced spheres are immune to agglomeration – and can be chemically released or alternatively used as part of an in-fiber device. Specifically, we propose to develop thermal fiber drawing from a macroscopic preform into a top-down scalable process for novel nanoparticle generation. This process will enable the production of large quantities of size-controllable nanoparticles consisting of a single or multiple materials combined in predesigned geometries. This process further paves the way to exploring new physics in confined geometries and prescribed length scales, such as the possibility of investigating the boundary between continuum fluid dynamics and quantum electrodynamics that emerges at the nanoscale. The objectives of our multidisciplinary study are twofold: first, to introduce a new materials-agnostic fabrication approach for nanospheres of arbitrary geometry, dimensions, and composition; second, to develop a new paradigm for fundamental fluid-dynamic studies offering a highly controlled environment for the observation of fluid instabilities involving multiple fluids co-flowing in hitherto unobtainable geometries and scales. In concert, these will set the stage for discoveries both fundamental and applied, spanning novel neuronal interface devices, delivery vehicles for pharmaceuticals, and potentially the chemical and electronics industries.