ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

 The Effect of Aging Time on t h e Properties of Nickel-Aluminium-Carbonate Layered Double Hydroxide Synthesized by Hydrothermal Method

M. Z. Bin Hussein, Y. H. Taufiq-Yap, R. Shahadan, and N. Y. Abd Rashid

Multifunctional Materials for Industrial Applications (MULIA) Research Group, Department of Chemistry, Universiti Putra Malaysia, 43400UPM, Serdang, Selangor, Malaysia

E-mail: mzobir@fsas.upm.edu.my

Abstract: Layered double hydroxide of nickel-aluminium with carbonate as an interlamellar anion was synthesized by hydrothermal technique (HT) at various aging times, 1 d, 2 d, and 4 d. For comparison, the same material was also prepared by conventional method (CM) using a shaker oil bath at 70°C and aging for 18 h. The atomic ratio r = n(Ni²⁺)/n(Al³⁺) of 4 was chosen in this study. Hydrothermal treatments performed on the aged samples enhanced the crystallinity, surface area, and the Ni content of the resulting materials. The r value of 3.2 was obtained for the sample prepared by CM technique compared to 3.5 for HT technique. Surface area analysis showed that the latter has a higher surface area than the former, 96 compared to around 22 m² g^-1. No aging time-surface area-dependent property can be clearly observed for the materials synthesized by HT technique. Pore size distribution shows that CM technique produced a sample with a sharp single peak centred at around 35 Å. A more broad pore size distribution was observed when the hydrothermal synthesis was adopted and the sample was aged for a day. On the other hand, a bimodal one was observed when the aging time increased to two days. Further increase of aging time to 3 d resulted in the dominance of the pore size distribution at 90 Å.

Full paper in Portable Document Format: 555a273.pdf

Chemical Papers 55 (5) 273–278 (2001)