Structure and Magnetism of Few-Layer Nanographene Clusters in Carbon Microspheres

The solid-phase pyrolysis method was used to synthesize carbon microspheres, consisting of clusters few-layer nanographene and amorphous carbon. Powders metal-free phthalocyanine polyethylene served as precursors the synthesized microspheres. products samples SPc(700) SPc(900) contained 4 1 atom % nitrogen, respectively, replacing in graphene lattice pyrrolic pyridinic coordination. There are no impurity nitrogen atoms polyethylene. sample showed strong paramagnetism with a concentration paramagnetic centers ∼5 × 1019 spin g–1 temperature-independent diamagnetism susceptibility χDia = −1 10–6 emu Oe–1. In temperature range 5–300 K, ferromagnetism also revealed dependence similar that ferromagnetic cluster glasses, maximum saturation magnetization, MSFM 3 10–2 g–1, coercive force, Hc 400 Oe, at Tsg 25 K. It shown is due π(p)-electrons zigzag-type edge states well atoms. experimental results interpreted based on correlation length. integral magnetic resonance absorption intensity closely resembles behavior magnetization component.