BaTiO3陶瓷中Gd、Ce的掺杂效应研究

在BaTiO3(BT)-Nb2O5-ZnO系统中引入硼硅酸盐助烧剂,加入Gd、Ce稀土氧化物以期获得中温烧结X7R陶瓷材料.研究发现,随着Gd用量的增加,单独掺杂时陶瓷室温介电常数先减小后增大,而与Ce复合掺杂时室温介电常数单调递增,分析认为,这是由于Gd在BT晶粒中对A位和B位的不同取代造成;随着Ce掺杂量的增大,室温介电常数减小,这与壳芯结构理论吻合.SEM图分析发现,Gd、Ce共掺杂BT陶瓷晶粒生长明显大于单独掺Gd或Ce的BT陶瓷,且陶瓷气孔率低,致密化程度高.

Doping effects of Gd and Ce in BaTiO3 ceramics

Borosilicate sintering aid,rare-earth Gd and Ce oxides were doped into BaTiO_3(BT)-Nb_2O_5-ZnO system in order to obtain the X7R materials sintered at intermediate temperature.The experiment results show that the dielectric constant at room temperature will first drop and then increase with the increase amount of Gd doped alone,whereas,when Gd and Ce Co-doped,the dielectric constant at room temperature show a steady increase.This can be explained by the change of the occupational sites of Gd in perovskite structure.When the doping amount of Ce increase,the dielectric constant at room temperature declines,this corresponds with the core-shell structure theory.The SEM test shows that the grains of Gd and Ce Co-doped BT ceramics grow bigger than that doped only with Gd or Ce,furthermore,it also has lower porosity and higher density.