Sains Malaysiana 44(7)(2015): 1003–1009

 

Subsolidus Solution and Oxide Ionic Conductivity of Nd-substituted Bismuth Yttria Fluorites

(Larutan Pepejal dan Kekonduksian Ion Oksida bagi Fluorit Bismuth Yittria yang Digantikan dengan Nd)

 

N. RAHMAN1, K.B. TAN1*, Z. ZAINAL1, C.C. KHAW2 & M.P. CHON1

 

1Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul Ehsan, Malaysia

 

2Department of Mechanical and Material Engineering, Faculty of Engineering and Science

Universiti Tunku Abdul Rahman, 53300 Setapak, Kuala Lumpur, Malaysia

 

Received: 13 August 2013/Accepted: 17 March 2015

 

ABSTRACT

Pure phase Bi1.6Y0.4-xNdxO3 solid solution with x = 0.00, 0.10 and 0.20 was successfully synthesised via conventional solid state method at 850°C in 21 h. The materials were refined and fully indexed with space group Fm-3m and lattice parameters, a ranging from 5.5124(1) Å to 5.5289(4) Å. Variation of the lattice parameters of these materials were found in an almost linear correlation with increasing Nd2O3 dopant concentration. Thermal analysis of Bi1.6Y0.4-xNdxO3 solid solution showed no thermal event that associated with any phase transition or weight loss within the studied temperature range of 35 to 900°C. The electrical properties of the samples were investigated by ac impedance analyser, HP4192 at temperature ranging from 25 to 800°C over frequency of 5 Hz to 13 MHz. Bi1.6Y0.3Nd0.1O3 exhibited the highest oxide ion conductivity among the synthesised samples in Bi1.6Y0.4-xNdxO3 solid solution.

 

Keywords: Fluorite; oxide ion conductivity; solid Solution; x-ray diffraction

 

ABSTRAK

Larutan pepejal Bi1.6Y0.4-xNdxO3 berfasa tulen dengan x = 0.00, 0.10 dan 0.20 telah berjaya dihasilkan melalui kaedah keadaan pepejal pada suhu 850°C dalam tempoh 21 jam. Bahan-bahan berkenaan telah dihalusi dan diindeks sepenuhnya dengan kumpulan ruangan Fm-3m dengan nilai parameter kekisi dalam lingkungan 5.5124(1) Å hingga 5.5289(4) Å. Parameter kekisi bahan-bahan berkenaan menunjukkan kolerasi yang berkadar terus dengan penambahan Nd2O3 yang didopkan. Analisis terma bagi larutan pepejal Bi1.6Y0.4-xNdxO3 tidak menunjukkan sebarang acara terma yang berkaitan dengan peralihan fasa atau penurunan berat dalam suhu kajian dari 35 hingga 900°C. Sifat elektrik dicirikan pada suhu ~ 30 hingga 800°C dengan menggunakan penganalisis AC impedans, HP4192 dalam julat frekunsi daripada 5 Hz hingga 13 MHz. Bi1.6Y0.3Nd0.1O3 mempunyai kekonduksian ion oksida yang paling tinggi antara fasa tulen yang dihasilkan dalam sistem larutan pepejal Bi1.6Y0.4-xNdxO3.

 

Kata kunci: Fluolit; kekonduksian oksida; larutan pepejal; pembelauan sinar-x

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*Corresponding author; email: tankarban@upm.edu.my

 

 

 

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