The Journal of American Chemistry Society recently published Professor Qiang Sun’s paper “Magnetism of phthalocyanine-based organometallic single porous sheet” .
Scientists have explored the possibility of having high surface area materials with isolated and exposed transition metal ions for many important applications such as magnetism, catalysis and hydrogen storage. The well-known graphene and BN sheet does have a high surface area, but it is extremely challenging to prevent introduced atoms from clustering.
Based on the recent experiments and the flexibility of assembling phthalocyanine (Pc), Professor Sun and his student, Jian Zhou at the Department of Materials Science and Engineering, systematically studied the stability, electronic structure and magnetism of TMPc (TM= Cr to Zn) porous sheets. They found that only the 2D MnPc framework has ferromagnetic ground state, which possesses conductive d bands in its spin down channel for effective p-d exchange. The other TMPc frameworks, showing semiconducting d bands, have antiferromagnetic or nonmagnetic ground states.
By applying Monte Carlo simulation based on the Ising model, they predicted that the Curie temperature of 2D MnPc is ~150 K, comparable to the highest Curie temperature achieved in experimentation of Mn doped GaAs. The results are very important for explorations of new types of 2D atomic sheet-based materials, which are of high interest for nanophysics applications and fundamental research.
For the journal article: [http://pubs.acs.org/doi/pdf/10.1021/ja204990j]