Electrical and magnetic performances of semiconductor based carbon nanoparticles

Abstract

The temperature-dependent resistivity, room temperature electron field emission, and magnetic performance within the temperature range of 2–300 K of previously chemically synthesized pure carbon nanoparticles (CNPs) from candle soot having particle sizes of ≈2–6 nm have been studied. The highest saturation magnetization and coercivity of ≈8.9 × 10−2 emu/g and ≈130.8 Oe were obtained at 2 and 4 K, respectively. We also determined that the turn-on electric field is ≈27 V/μm with a current density of ≈0.8 × 10−8 A/cm2 @ 20 V/μm. The temperature vs electrical resistivity and applied high electric field (EA) vs electron emission show the tunneling from one conductive sp2 C=C cluster to another separated by an sp2 C=C cluster (and/or an insulating sp3 C–C cluster). The magnetic, as well as the electric, field emission results imply that CNPs could be useful for the fabrication of spintronic as well as field-emission display devices.