Boron-doped carbon microspheres

A chemical vapor deposition (CVD) procedure has been used for the synthesis of boron-doped carbon microspheres (CSMs) using BF3/MeOH as the boron source, and acetylene as the carbon source. The boron-doped carbon microsphere samples were characterized by transmission electron microscopy (TEM), Raman spectroscopy and laser ablation mass spectrometry analysis. The average diameter and the shell thickness of the carbon microspheres are strongly influenced by the boron content. The intensity of the D-band laser excitation line increased after the boron incorporation into the carbon microspheres. Electrical conductivity of the boron-doped carbon microspheres has been measured. The conductivity of the B-doped microsphere sample is lower than that of the undoped sample by about two orders of magnitude. This could be ascribed to a higher degree of charge localization which impedes the charge transport in this material compared to the undoped material. (C) 2008 Elsevier B.V. All rights reserved.