Fabrication, characterization and physical properties of Co-doped SnO particles via hydrothermal method

Novel plate-like Sn1-xCoxO particles have been successfully synthesized by a template-free hydrothermal growth method. Field emission scanning microscopy and transmission electron microscopy results show that the obtained particles are consist of nanosheets with a thickness of ∼10 nm. X-ray diffraction results show that the Sn1-xCoxO possesses typical tetragonal structure, Co-doping has certain influence on the host lattice structure and Co would occupy different positions (CoSn and Coi) with different doping concentrations. And the optical band gap of the samples firstly narrows and then widens as the positions of Co changing from substituted sites to interstitial sites. Meanwhile, room-temperature ferromagnetism originated from the double exchange interactions between the O 2p and Co 3d states is discovered as well, and the ferromagnetism firstly increases and then decreases with Co concentration increasing.