The Malaysian Journal of Analytical Sciences Vol 11 No 1 (2007): 294 – 301

 

 

EFFECT OF NUMBER OF WASHING ON THE CHARACTERISTICS OF COPPER OXIDE NANOPOWDERS

 

E.N. Muhamad¹, R. Irmawati^*1 , A.H. Abdullah¹ , Y.H. Taufiq - Yap¹ 

and S.B. Abdul Hamid²

 

¹Department of Chemistry, Faculty of Science, Universiti Putra Malaysia,

43400 UPM Serdang, Selangor, Malaysia.

²Combinatorial Technology and Catalysis Centre, Universiti Malaya,

50603 Lembah Pantai, Kuala Lumpur, Malaysia.

 

*Corresponding author: irmawati@science.upm.edu.my

 

Abstract

The effect of washing on physico-chemical properties of copper oxide prepared via precipitation method was investigated by means of  X-ray diffraction (XRD ), Fourier Transform Infrared (FTIR), BET surface  area  measurement  and  scanning electron microscopy (SEM ). Increasing the number of washing has successfully removed undesired nitrate resulting in high surface area CuO catalysts from 8.5 to 15.9 m² g^-1. XRD pattern of thes e oxides gave well crystalline of  CuO  with main peak appeared at 2 = 35.5°, 38.7° and 48.7°. The powders obtained are of uniform size distribution, finely grained with an average size of 20 nm. In addition, an investigation on the mobility of oxygen species carried out using transient technique  i.e. temperature programmed reduction (TPR) shows that reduction peak maximum moved towards lower reduction temperature with the increasing number of washing. This indicates the ease of reducibility of the oxide when the precursor is washed several times. It is clearly found that particle size was profound effect on the catalytic activity of CuO.

 

Keywords: copper oxide, precipitation method, effect of washing, TPR, reduction

 

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