HIERARCHICAL CARBON NANOTUBE-INORGANIC HYBRID STRUCTURES INVOLVING CNT ARRAYS AND CNT FIBERS

Abstract

Carbon nanotube-inorganic hybrid materials have stimulated a new boost in CNT research as a new class of multifunctional materials with properties distinct from the well-known CNT composites. Synergistic effects based on interfacial charge and heat transfer processes commend these hybrids for use in photocatalysis, gas sensors and in electrochemical devices. A major challenge is the synthesis of hybrids with hierarchical architectures and controlled interfaces. Common wet-chemical techniques have the major drawback that the CNT array typically collapses upon drying due to stresses imposed by the surface tension of the solvent. In this work, we synthesized hierarchical hybrids with coherent 3D architectures using unique CNT fibers, based on the "Cambridge process" as well as vertical arrays of CNTs ("carpets"). We demonstrate that separating the liquid reactants from the CNT array is key to preserving the hybrid's architecture. In addition, we show that the presence of benzyl alcohol as a linking agent is beneficial to maximizing the interfacial area in TiO 2 -coated CNT fibers.