Nanocrystalline Pd/carbon nanotube composites synthesized using supercritical fluid for superior glucose sensing performance

With the aid of supercritical carbon dioxide (SCCO₂), which has gas-like diffusivity, extremely low viscosity, and near-zero surface tension, the synthesized nano-sized Pd particles (approximately 5 nm in diameter) are uniformly distributed on carbon nanotubes (CNTs). The decoration density of Pd nanoparticles on the CNTs can be simply controlled, without varying the particle size, by adjusting the Pd hexafluoroacetylacetonate precursor to CNT ratio. Since the Pd nanoparticles are highly dispersed and tightly anchored on the CNTs, the obtained composite shows enhanced electro-sensing performance toward glucose compared to that of the control sample prepared using a conventional deposition process (without SCCO₂).