Site-specific functionalization of anisotropic nanoparticles: from colloidal atoms to colloidal molecules

TY - JOUR

T1 - Site-specific functionalization of anisotropic nanoparticles: from colloidal atoms to colloidal molecules

AU - Li, Fan

AU - Yoo, Won Cheol

AU - Beernink, Molly B

AU - Stein, Andreas

N1 - Keywords: Anisotropy; Colloids; Methods; Nanoparticles

PY - 2009

Y1 - 2009

N2 - Multipodal nanoparticles (NPs) with controlled tethers are promising principal building blocks, useful for constructing more complex materials, much like atoms are connected into more complex molecules. Here we report colloidal sphere templating as a viable means to create tetrapodal NPs with site-specific tethers. Amorphous sol-gel materials were molded by the template into shaped NPs that mimic tetravalent atoms but on the length scale of colloids. Synthetic methods were developed to modify only the tips of the tetrapods with a range of possible functional groups to generate anisotropic NPs capable of directional bonding to other NPs. We also illustrate that sets of tethered "colloidal atoms" can assemble themselves into "colloidal molecules" with precise placement of the modifying colloids. The templating and tethering approaches to these anisotropic colloidal building blocks and the assembly methods are applicable to many compositions regardless of crystal structure, therefore lending themselves to the fabrication of complex assemblies, analogous to those found in the molecular regime.

AB - Multipodal nanoparticles (NPs) with controlled tethers are promising principal building blocks, useful for constructing more complex materials, much like atoms are connected into more complex molecules. Here we report colloidal sphere templating as a viable means to create tetrapodal NPs with site-specific tethers. Amorphous sol-gel materials were molded by the template into shaped NPs that mimic tetravalent atoms but on the length scale of colloids. Synthetic methods were developed to modify only the tips of the tetrapods with a range of possible functional groups to generate anisotropic NPs capable of directional bonding to other NPs. We also illustrate that sets of tethered "colloidal atoms" can assemble themselves into "colloidal molecules" with precise placement of the modifying colloids. The templating and tethering approaches to these anisotropic colloidal building blocks and the assembly methods are applicable to many compositions regardless of crystal structure, therefore lending themselves to the fabrication of complex assemblies, analogous to those found in the molecular regime.

U2 - 10.1021/ja908364k

DO - 10.1021/ja908364k

M3 - Journal article

C2 - 19954228

SN - 0002-7863

VL - 131

SP - 18548

EP - 18555

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

IS - 51

ER -