摘要
以硝酸锌、硝酸铝和尿素为原料，采用均匀沉淀法合成了不同掺杂量的掺铝氧化锌（ZAO）前驱体，在400℃煅烧获得粒径均匀的纳米ZAO粉体。经X射线衍射（XRD）和扫描电子显微镜（SEM）分析表明，Al^3＋取代了Zn^2＋的位置，形成Al／ZnO固溶体，保持了ZnO的结构，实验最终产物为六方晶系纤锌矿结构的纳米ZAO粉体，形状为球状或类球状。对所得产物在8．2～12．4GHz频率范围内进行了介电常数的测试。结果表明，随着Al元素掺杂量的增加，ZAO粉体复介电常数的实部和损耗逐步增大，但是当Al掺杂浓度〉11％（原子分数）时，ZAO粉体中出现了铝酸锌（ZnAl2O4），Al不再起掺杂作用，复介电常数的实部和损耗不再增加。
ZAO precursors were synthesized by uniform precipitation-method from zinc nitrate （Zn（NO3）2）,aluminum nitrate （Al（NO3）3） and earbamide. The nanometer ZAO powders with different Al content were obtained after heat treat ZAO precursors at 400℃ for 3h. The crystalline phase, mierostrueture and the dielectric property for different samples were analyzed and the influence of Al content on the crystalline phase, microstructure and the dielectric property were investigated. The XRD results indicate that the spectra of the ZAO powder is almost the same to that of pure ZnO powder when the Al content is below 11at%, indicating that the Al atoms do enter the ZnO crystal lattice and substitute the position of Zn. The structure of nanometer ZAO particles with the hexagonal system and wurtzite structure is global or similar one. The dielectric real part and dielectric loss of the ZAO powders is dominated by the A1 content in the ZAO powder. With the increase of Al concentration, both the dielectric real part and dielectric loss increase sharply and reaches the maximum value when the Al content is 11at%. When the Al content is above 11at%, both dielectric real part and dielectric loss decrease obviously with the increase of Al content due to the formation of ZnAl2O4 in the samples.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2008年第4期667-669,共3页
Journal of Functional Materials
基金
国家自然科学基金资助项目(90305016)
关键词
ZAO粉体
均匀沉淀法
微波介电性能
nano- ZAO powder
homogenous precipitation
dielectric dissipation
