Sains Malaysiana 38(3): 401-405(2009)

Effect of Stoichiometric Composition and Different Metal Salts on the Phase

Formation of Cerate-Zirconate Ceramics

(Kesan Komposisi Stoikiometri Dan Garam-Logam Berbeza

Ke atas Pembentukan Fasa Seramik Serat-Zirkonat)

Nafisah Osman¹*, I.A. Talib² & H.A. Hamid¹

¹Faculty of Applied Sciences, Universiti Teknologi MATRA

02600 Arau, Perlis, Malaysia

²Faculty of Science & Technology, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E. , Malaysia

Diserahkan: 6 Ogos 2008 / Diterima: 29 Ogos 2008

  ABSTRACT

The effects of compositions and different metal salts on the phase of Ba(Ce,Zr)O₃ perovskite ceramics derived from the solid state-reaction, sol-gel and Pechini methods are studied. X-ray diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR) were used to study the phase formation of the compound. It was found that the purity of Yb-doped Ba(Ce,Zr)O₃ strongly depends on the stoichiometric compositions and metal salts of  the raw materials. A high purity compound at relatively low temperature was obtained  only when the powder of Ba(Ce_0.8Zr_0.2)_0.95Yb_0.05O_2.975 was prepared from metal nitrate salts. Result of FTIR also confirmed that there was no carbonate species present in the sample prepared by Pechini method after it was sintered at 1400^oC.

Keywords: Cerate-zirconate; Fourier transform infrared spectroscopy; phase formation; stoichiometric composition; x-ray diffraction

ABSTRAK

Kesan komposisi dan garam-logam berbeza ke atas pembentukan fasa seramik perovskit Ba(Ce,Zr)O₃ yang disediakan secara tindak balas keadaan pepejal, sol-gel dan Pechini telah dikaji. Pembelauan sinar-x dan spektroskopi transformasi Fourier infra-merah (FTIR) telah digunakan untuk mengkaji pembentukan fasa sebatian tersebut. Didapati bahawa ketulenan fasa bagi Ba(Ce,Zr)O₃ terdop Yb sangat bergantung kepada komposisi stoikiometri dan juga garam-logam bahan-bahan asas. Ketulenan fasa yang tinggi dapat diperoleh pada suhu yang rendah hanya apabila serbuk Ba(Ce_0.8Zr_0.2)_0.95Yb_0.05O_2.975 disediakan daripada garam-garam yang berasaskan nitrat. Keputusan  FTIR juga mengesahkan bahawa tiada lagi sisa karbonat yang hadir dalam sampel yang disediakan secara kaedah Pechini apabila disinter pada suhu 1400 ^oC.

Kata kunci: komposisi stoikiometri; pembelauan sinar-x; serat-zirkonat; pembentukan fasa; spektroskopi transformasi Fourier infra-merah

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*Pengarang untuk surat-menyurat; email: fish@perlis.uitm.edu.my