(北京工業(yè)大學 材料科學與工程學院, 北京 100022)
摘 要: 使用高溫固相燒結(jié)法制備不同化學劑量比的CuAlO2陶瓷，研究CuxAlO2(0.92≤x≤1.0)中Cu、Al摩爾比的相對變化對其結(jié)構和導電性能的影響。結(jié)果表明：CuxAlO2(0.92≤x≤1.0)陶瓷片的結(jié)構和密度隨著x值的增大，樣品的結(jié)晶性逐漸變好，密度也逐漸增大，在x為0.98時，得到密度最大(5.02 g/cm3)且結(jié)晶良好的純相CuAlO2；樣品的光學帶隙均約為3.44 eV；隨著x值的增加，室溫電導率先增大然后減小，在x為0.98時得到最大電導率為8.03×10−3 S/cm；電導率隨溫度的升高而顯著增大，且曲線在100~300 K之間很好地符合Arrhenius關系，x為0.98時激活能最低，僅為0.085 eV；在所研究的成分范圍內(nèi)，CuAlO2陶瓷的導電能力主要取決于陶瓷片的致密度。
關鍵字: CuAlO2陶瓷；銅鐵礦結(jié)構；致密度；電導率；熱激活能
（College of Materials Science and Engineering, Beijing University of Technology, Beijing 100022, China）
Abstract:The nonstoichiometric CuxAlO2 ceramics were successfully prepared by solid state sintering at high temperature. The effects of the x value on the band gap and electrical conductivity were investigated. The results show that the structure and density of CuxAlO2 ceramic plates show a notable improvement with the increasing content of Cu. The maximum value of density is 5.02 g/cm3 for CuxAlO2 ceramic with x=0.98 and the XRD pattern indicates that it is a pure CuAlO2 phase. The optical band gap of CuxAlO2 ceramics is about 3.44 eV. The conductivity at room temperature increases first and then reduces with the increasing content of Cu. The maximum conductivity is about 8.03×10−3 S/cm with x=0.98. The temperature dependence of electrical conductivity agrees well with the Arrhenius relationship, indicating that the electrical conducting is ascribed to thermal activation in the range of 100−300 K. The minimal value of the activation energy is estimated 0.085 eV. The electrical conductivity of CuxAlO2 ceramics mainly depends on the density of the samples in the investigating range.
Key words: CuAlO2 ceramics; delafossite; density; electrical conductivity; activation energy
