Magnetic properties of carbon phases synthesized using high pressure-high temperature treatment

TL;DR

This study investigates the magnetic properties of carbon phases synthesized under high pressure and temperature, revealing that the preparation conditions used do not produce bulk magnetic carbon, despite structural transformations.

Contribution

It provides new insights into the synthesis conditions affecting magnetic properties of carbon phases at high pressure and temperature.

Findings

Structural transformation from C60 to graphite-like carbon confirmed

Samples did not exhibit bulk magnetic properties

High pressure-high temperature treatment alone is insufficient for magnetic carbon

Abstract

Two sets of samples were synthesized at 3.5 GPa near the point of C60 cage collapse at different annealing times. A clear structural transformation from mixture of C60 polymeric phases to graphite-like hard carbon phase was confirmed by X-ray diffraction and Raman spectroscopy. Magnetic force microscopy and superconducting quantum interference device were used to characterize the magnetic properties of the synthesized samples. We found that the sample preparation conditions used in this study are not suitable to produce bulk magnetic carbon.