1. University of New Mexico/NSF Center for Micro-Engineered Materials, The Advanced Materials Laboratory, 1001 University Boulevard SE, Albuquerque, New Mexico 87106, USA
2. Sandia National Laboratories, Direct Fabrication Department, 1831, Albuquerque, New Mexico 87185, USA

Correspondence to: C. Jeffrey Brinker^1,2 Correspondence and requests for materials should be addressed to C.J.B. (e-mail: Email: cjbrink@sandia.gov).

Abstract

Particles possessing nanometre-scale pores of well-defined size and connectivity are of interest for catalysis, chromatography and controlled release of drugs, and as fillers with low dielectric constant, pigments and hosts for optically active compounds¹,². Silica containing ordered mesopores (of nanometre-scale width) can be prepared by templating of surfactant³,⁴ and block copolymer⁵ liquid-crystalline mesophases, and interfacial phenomena have been used to control the macroscopic form of these materials, providing mesoporous particles¹,⁶, fibres⁷,⁸ and films⁹,¹⁰. A variety of spherical or nearly spherical particles has been reported¹,⁶,⁷,^{11, 12, 13}, but the degree of ordering and the range of the porous mesostructures have been limited. Here we report a rapid, aerosol-based^{14, 15, 16} process for synthesizing solid, well-ordered spherical particles with stable pore mesostructures of hexagonal and cubic topology, as well as layered (vesicular) structures. Our method relies on evaporation-induced interfacial self-assembly¹⁷ confined to spherical aerosol droplets. This simple, generalizable process can be modified for the formation of ordered mesostructured thin films.