水热时间对Co掺杂ZnO微结构与磁性的影响

Influence of Hydrothermal Time on the Microstructure and Magnetism of Co-doped ZnO

采用水热法制备了Co掺杂ZnO粉晶,研究了水热时间t(t=2,3,6 h)对其微结构、形貌和磁性的影响。结果表明:随水热时间增加,Co掺杂ZnO晶胞参数和微应变减小,c/a值增加,均具有六方柱形貌。水热时间为2 h时显示弱铁磁性,合成时间为3 h时具有最强的铁磁特性,六方纳米柱形状明显变长,结晶性能最好。水热时间为6 h时显示为顺磁性,六方纳米柱形貌有"融化"趋势。相对于未掺杂ZnO,Co掺杂有利于单一ZnO相的形成。

Co-doped ZnO powder crystals have been synthesized by hydrothermal method. The influence of hy- drothermal time t（t=2,3,6h） on the microstructure, morphology and magnetism of these specimen has been stud- ied. It was found that the lattice constant and microstraln decrease while the ratio increases for Co-doped ZnO with lengthening of hydrothermal time, which all has hexagonal rod morphology. The synthesized Co-doped ZnO prepared for 2h shows weak ferromagnetic orders and the room temperature ferromagnetic property has been obviously enhanced when it hydrogenated for 3 hours. Moreover it has the longest hexagonal rods and the optimist crystallization. While Co-doped ZnO shows paramagnetism and the hexagonal rods have the trends of melt-out when it hydrogenated for 6 hours. Compared with the non-doped ZnO, Co-doping has been helpful to the formation of single phase ZnO with wuttzite structure.