"Functionalization of silicon nanowire surfaces with metal-organic frameworks"

Nian Liu: Yan Yao, Judy J. Cha, Matthew T. McDowell, Yu Han, and Yi Cui; Nano Research , 11/29/11.

Additional Authors: Yan Yao, Judy J. Cha, Matthew T. McDowell, Yu Han, and Yi Cui

Abstract:

Metal–organic frameworks (MOFs) and silicon nanowires (SiNWs) have been extensively studied due to their
unique properties; MOFs have high porosity and specific surface area with well-defined nanoporous structure,
while SiNWs have valuable one-dimensional electronic properties. Integration of the two materials into one
composite could synergistically combine the advantages of both materials and lead to new applications. We
report the first example of a MOF synthesized on surface-modified SiNWs. The synthesis of polycrystalline
MOF-199 (also known as HKUST-1) on SiNWs was performed at room temperature using a step-by-step (SBS)
approach, and X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, transmission
electron microscopy, and energy dispersive spectroscopy elemental mapping were used to characterize the
material. Matching of the SiNW surface functional groups with the MOF organic linker coordinating groups was found to be critical for the growth. Additionally, the MOF morphology can by tuned by changing the soaking time, synthesis temperature and precursor solution concentration. This SiNW/MOF hybrid structure opens new avenues for rational design of materials with novel functionalities.