Comparative study of structures and electrical properties in cobalt fullerene mixtures by systematic change of cobalt content

摘要: Abstract A systematic study is performed for the Co content-dependent structure evolution and electrical properties in cobalt (Co)–fullerene (C60) mixtures broad content region. Raman analysis confirms that mixture has a saturation composition of Co5C60 compound formation. An important role covalent Co–C bonds characteristic Co–C60 compounds concluded from peak shifts symmetry lowering C60. The Co-dilute exhibit semiconductive nature represented by activated transport shallow mid-gap states. Co-dense are characterized hopping conduction (including variable range hopping) attributed to clusters/nanoparticles matrix percolated metallic conduction, depending on content.