Ag和Cu共掺对ZnO纳米棒形貌和光学性质的影响

The Cooperative Effect of Ag and Cu Co-doping on Morphology and Optical Properties of ZnO Nanorods

氧化锌(ZnO)具有独特的物理和光学性质,对ZnO进行适当的掺杂对调节其光电子器件的光电性能有重要的作用。采用低温水热法合成了未掺杂、Ag掺杂、Cu掺杂和Ag+Cu共掺杂的ZnO纳米棒(NRs)阵列,同时研究了单掺杂和共掺杂对ZnO NRs的形貌、结构和光学性能的影响。结果表明:不同掺杂条件下制备的ZnO NRs均为纤锌矿结构,具有较强的(002)晶面衍射峰,且Ag+Cu共掺杂与未掺杂的ZnO NRs的衍射峰相似,这是由于比Zn~(2+)半径小的Cu~(2+)掺杂和比其大的Ag~+掺杂引起的晶格畸变的协同影响所致。受纳米棒尺寸效应和能带重整化效应的双重影响,所有掺杂的ZnO NRs的紫外发射峰红移。与未掺杂的ZnO NRs相比,由于氧空位等缺陷浓度的增加,共掺样品的可见光发射峰的强度略增加,介于Ag或Cu单掺杂之间。因此,Ag和Cu的共同掺杂为ZnO NRs更加广泛地应用于光电领域提供了可能。

Zinc oxide(ZnO)has unique physical and optical properties.Proper doping of ZnO plays an important role in adjusting the photoelectric properties of its optoelectronic devices.In this paper,undoped,Ag-or Cu-doped,and Ag+Cu co-doped ZnO nanorod(NRs)arrays were synthesized by hydrothermal method at low temperature.Meanwhile the influence of doping and co-doping on the morphology,structure,and optical properties of ZnO NRs was investigated.The results show that the ZnO NRs prepared under different doping conditions were of wurtzite structure with strong(002)diffraction peak,and the diffraction peak of Ag+Cu co-doped ZnO NRs was similar to that of undoped ZnO NRs,which was due to the synergistic effect of lattice distortion caused by smaller radius Cu 2+doping and larger radius Ag+doping than Zn 2+.Affected by the size effect of nanorods and the Band Gap Renormalization effect,the UV emission peaks of all doped ZnO NRs had a red shift.Compared with that of undoped ZnO NRs,the intensity of visible emission peak of co-doped ZnO NRs increased slightly owing to the increasing defect concentration such as oxygen vacancy,and lay between that of AZO NRs and CZO NRs.Therefore,the co-doping of Ag and Cu makes it possible for ZnO NRs to be widely used in photoelectric field.