Malaysian Journal of Analytical Sciences Vol 20 No 6 (2016): 1458 – 1466

DOI: http://dx.doi.org/10.17576/mjas-2016-2006-26

 

 

 

PREPARATION OF LANTHANUM STRONTIUM COBALT OXIDE POWDER BY A MODIFIED SOL-GEL METHOD

 

(Penyediaan Serbuk Lantanum Strontium Kobalt Oksida Melalui Kaedah Sol-Gel Terubahsuai)

 

Abdullah Abdul Samat¹, Mahendra Rao Somalu¹*, Andanastuti Muchtar^1,2, Nafisah Osman³

 

¹Fuel Cell Institute

²Department of Mechanical and Materials Engineering, Faculty of Engineering and Built Environment

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

³Faculty of Applied Sciences,

Universiti Teknologi MARA, 02600 Arau, Perlis, Malaysia

 

*Corresponding author: mahen@ukm.edu.my

 

 

Received: 21 October 2015; Accepted: 14 June 2016

 

 

Abstract

A simple low temperature synthesis route has been presented for the preparation of single perovskite phase of La_0.6Sr_0.4CoO_3-δ (LSCO) for cathode application in intermediate temperature proton conducting solid oxide fuel cell (SOFC). A wet chemical method namely a modified sol-gel method has been applied in this work. In this method, a combined citric acid and ethylenediaminetetraacetic acid (EDTA) has been used as a chelating agent. Ethylene glycol (EG) and activated carbon (AC) have been used as surfactants in this process. The synthesized powders were characterized by X-ray diffractometer (XRD), scanning electron microscope (FESEM) equipped with energy dispersive X-ray (EDX) spectrometer and particle size analyzer (PSA) for phase formation, morphology and particle size analysis, respectively. XRD result revealed that a single LSCO perovskite phase for both surfactants formed at calcination temperature of 900 °C. The produced single phase powders consist of homogeneous and almost identical shape of particles as shown in SEM images. However, the powder prepared using EG has a smaller average particle size diameter as compared with the powder prepared using AC which is 149 nm and 190 nm, respectively.

 

Keywords:  modified sol-gel, surfactant, cathode, solid oxide fuel cell, single perovskite phase of La_0.6Sr_0.4CoO_3-δ

 

Abstrak

Satu kaedah sintesis ringkas pada suhu rendah telah dibentangkan untuk menyediakan fasa tunggal perovskit La_0.6Sr_0.4CoO_3-δ (LSCO) bagi aplikasi katod di dalam konduktor proton sel bahan api oksida pepejal (SFOP) suhu sederhana. Satu kaedah kimia basah, iaitu, kaedah sol-gel terubahsuai telah digunakan dalam penyelidikan ini. Melalui kaedah ini, gabungan asid sitrik dan asid atelindiamintetrasetik (EDTA) telah digunakan sebagai agen pengikat. Etilena glikol (EG) dan karbon teraktif (AC) telah digunakan sebagai surfaktan dalam proses ini. Serbuk yang disintesis telah dicirikan dengan menggunakan pembelauan sinar-X (XRD), mikroskop elektron pengimbas (SEM) dilengkapi dengan spektroskopi sinar-X sebaran tenaga (EDX) dan penganalisis saiz zarah (PSA) bagi analisis pembentukan fasa, morfologi dan saiz zarah, masing-masing. Keputusan XRD menunjukkan fasa tunggal perovskit LSCO bagi kedua-dua surfaktan telah terbentuk pada suhu pengkalsinan 900 °C. Serbuk berfasa tunggal yang terhasil terdiri daripada zarah yang homogen dan mempunyai bentuk yang hampir sama seperti ditunjukkan dalam imej SEM. Walau bagaimanapun, serbuk yang dihasilkan menggunakan EG mempunyai purata diameter saiz zarah yang lebih kecil iaitu 149 nm berbanding serbuk yang dihasilkan menggunakan AC iaitu 190 nm.

 

Kata kunci:  sol-gel terubahsuai, surfaktan, katod, proton sel bahan api oksida pepejal, fasa tunggal perovskit La_0.6Sr_0.4CoO_3-δ

 

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