Fabrication of metal-nanoparticle/carbon-fiber composites having a microtube-array morphology

In the current work, we succeeded in incorporation of Pt ions into sisal fiber (SF) – a biological matrix with a characteristic morphology of microtube array, and in subsequent in situ synthesis of Pt nanoparticles of ca. 3.6 nm. Carbonization of the SF with Pt nanopaticles at 400°C produced Pt-nanoparticle/carbon-fiber composite, preserving the initial microtube-array morphology of SF. It is interesting that the walls of neighboring microtubes and the middle lamella between these microtubes were fused by carbonization, and a homogeneous wall was formed. Although the size of Pt nanoparticles was enhanced to ca. 5.3 nm after carbonization, the solid matrices (from cellulose to carbon) acted as effective barriers against the growth of Pt nanoparticles. The Pt-nanoparticle/carbon-fiber composite combines several important aspects, including the morphologies of fiber and microtube-array, carbon matrix, and Pt nanoparticles. Thus it might be a novel type of catalyst and have potential applications in many fields.