Electrospun carbon nanofibrous mats surface-decorated with Pd nanoparticlesvia the supercritical CO2 method for sensing of H2

Abstract

Carbon nanofibers (in the form of an overlaid mat) were prepared by electrospinning of polyacrylonitrile followed by stabilization in air and carbonization in argon. Pd nanoparticles were then deposited on the surface of nanofibers by using Pd(acac)₂ as the precursor via the supercritical CO₂ method followed by pyrolysis at 600 °C. Structural characterizations indicated that the Pd nanoparticles were composed of single-crystalline clusters with sizes of a few nanometers. The hydrogen sensing properties of electrospun carbon nanofibrous mats surface decorated with Pd nanoparticles were investigated. The results indicated that the resistivity of Pd-decorated nanofibrous mats decreased linearly with the increase of H₂ volume fraction from 0 to 0.7 in H₂/N₂ mixture gas, and the response showed excellent reversibility.