Sol-gel法制备Co-Mn共掺杂ZnO粉体和红外发射率的研究

Infrared Emissivity of Co-Mn Co-Doped ZnO Powders Synthesized in Sol-Gel Method

采用溶胶．凝胶法制备不同Co-Mn共掺杂浓度的ZnO前驱体，并在不同温度下对其进行煅烧。由x射线衍射分析可知，煅烧后所得粉体均为六角纤锌矿结构的ZnO，并且沿（101）晶面择优生长，没有生成杂质相。扫描电子显微镜结果表明，ZnO晶粒均为不规则多面体状，并随着煅烧温度升高和掺杂浓度增加，晶粒先增大而后减小。由x射线光电子谱可知，掺入的杂质是以Co2＋和Mn2＋的形式取代ZnO晶格中的zn2＋。采用IR-2型红外发射率测试仪测量粉体在3—5和8～14μn波段的平均红外发射率e，结果表明，随煅烧温度的升高和掺杂浓度的增加，粉体的e值降低，在煅烧温度为1200℃，Co与M_n的掺杂浓度分别为9％和1％（原子比）时，共掺杂ZnO粉体在3～5和8～14μn波段e值最低，分别达0．36和0．762。对CO-Mn共掺杂影响ZnO粉体的红外发射率的机理进行探讨。

The Co-Mn co-doped precursors of ZnO powder, synthesized in sol-gel method, were sintered at different temperatures. The Co-Mn co-doped ZnO powders were characterized with X-my diffraction, X-ray photoelectron spec- troscopy, scanning electron microscopy, energy dispersive spectroscopy, and IR-2 Dual-Band Infrared emissometer. Only hexagonal wurtize phased ZnO, with（ 101 ）preferential growth orientation, was observed of all the sintered powders. The re- sults show that the sintering temperature and contents of Co and Mn significantly affect the average IR emissivity ε. For example,as the sintering temperature and dopant contents increased,the average IR emissivity e in 3 ~ 5 μn and 8- 14 tan bands decreased, but the size of irregular polyhedral grain increased. Sintered at 1200℃, the average IR emissivity in 3 ~ 5 pan and 8 ~ 14μn bands of ZnO powders with Co content of 9% （at） and Mn content of 1%, was the lowest,O.36, and 0,762,respectively.The possible mechanism responsible for dependence of reduction of IR emissivity on Co-Mn co- doping was also tentatively discussed.