材料科學(xué)與工程 材料物理與化學(xué)，外文文獻(xiàn)翻譯及原文

Investigations on the mixed conductivity of copper tantalate

鉭酸銅混合導(dǎo)電性的研究報(bào)告

Abstract
Polycrystals of CuTa,O, were prepared by solid-state reaction in air at 1200°C with variations of stoichiometry (x) in thecopper oxide ratio. They were examined by X-ray diffraction. A defect of copper oxide during the synthesis leads to anexcess of Ta,O, phase in the sample and an excess of copper oxide gives a single phase compound. The total conductivitywas determined by impedance measurements and the electronic conductivity was estimated by the Hebb-Wagner method. Atroom temperature, the total conductivity of samples in equilibrium with copper is about 10-7-10~h S cm-‘. No significantchanges were observed for x = 0.8 and 1.O, but the total and the partial conductivities are higher for x = 1.2.In all cases, themeasured electronic conductivity seems to be mainly of n-type and the electronic transport number is close to 0.5-0.6,independent of the temperature and stoichiometry. The nature of the mixed conduction is discussed in relation to Cu’ ions inthe structure.

摘要
CuTa2O6多晶通過固相反應(yīng)在空氣中1200攝氏度時(shí)反應(yīng)得到，其中氧化銅的化學(xué)計(jì)量（X）會(huì)有變化。通過X-射線衍射檢查，合成過程中的氧化銅的一種缺陷導(dǎo)致Ta2O5過量，樣品中的相與過量的氧化銅會(huì)得到一種單相化合物?？傠妼?dǎo)率的測定由阻抗測量和電子電導(dǎo)率的估計(jì)組成，叫做海伯-瓦格納法。在室溫下，在銅平衡的樣品的總導(dǎo)電率約10-7-10-6 Scm-1。觀察得到當(dāng)X=0.8和X=1時(shí)，電導(dǎo)率沒有什么明顯變化，但是在X=1.2時(shí)，總電導(dǎo)率和部分電導(dǎo)率比較高。在所有情況下，測得的電子傳導(dǎo)性主要是n型導(dǎo)電，而且電子遷移數(shù)接近0.5-0.6，有獨(dú)立的溫度和化學(xué)計(jì)量。通過結(jié)構(gòu)中的銅離子來討論混合傳導(dǎo)的性質(zhì)。