STEIN RESEARCH GROUP

POROUS SOLIDS — NANOCOMPOSITES — SELF-ASSEMBLED FRAMEWORKS

Shaped Nanoparticles

Porous nano-objects with defined sizes and structures are particularly interesting, for example, as capsules for enzymes, a means of drug delivery, or building blocks for larger nanostructures. The production of such tiny, three-dimensional objects in a targeted and controlled manner—and as simply and efficiently as possible—remains a challenge for scientists. In the proposed research, new processes will be developed for the production of nanoscopic cubes and other interesting shapes that are not usually accessible by conventional methods. Instead of building particles from smaller units, controlled disassembly of larger, lattice-like structures will be used. Many conventional methods for the production of nanoparticles suffer because the growing particles tend to clump together, making it difficult to achieve a uniform size. The shape of the particles can hardly be influenced at all. The alternate approach to be studied involves first building up a lattice structure in an ultrasmall mold and then disassembling it to get the desired shape. The molds used for the lattice are tiny plastic spheres, which assemble themselves like marbles in a box. Between the spheres in this structure, there are small, shaped spaces, which will be filled with precursors that convert into shaped nanoparticles with tiny pores when the spheres are burnt off by heating. By altering the mold, the sizes and shapes of the resulting, sponge-like particles can be controlled. The shaped, porous nanoparticles provide a starting point for complex nanostructures with potential applications in power storage, detection and pharmaceutics.

. . Related Research: •Molding Porous Nanoparticles •Nanocubes Related Publications

Mesoporous carbon tetrapod Mesoporous silica cubes

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