Sains Malaysiana 39(2)(2010): 275–280
Silica Aerogels’ Nanostructure Studied using Small Angle
Neutron Scatterring Technique
(Struktur Nano Aerogel Silika dikaji Menggunakan
TeknikSerakan Sudut Kecil Neutron)
Noorddin Ibrahim* & Tan Chier Fang
Department of Physics, Faculty of
Science
Universiti Teknologi Malaysia (UTM), 81310
Skudai, Johor, Malaysia
Diserahkan: 28 Mei 2009 / Diterima:
12 Ogos 2009
ABSTRACT
Small angle neutron scattering (SANS) technique has been widely employed in probing the microstructure
of amorphous materials in the nanometer range. In aerogels system, the size
range of 1 – 100 nm is of particular interest since the structural units, such
as the pores and particles, often fall in this range. In a typical scattering
experiment, scattered neutron intensity is measured as a function of the
scattering angle. Various plots of intensity I(Q) and scattering vector, Q, can
provide information about fractal dimensions, and particle and cluster sizes.
In this study, SANS facilities, at Nuklear Malaysia (NM) and Badan Tenaga Atom Nasional (BATAN), Indonesia were used to analyse
particle and cluster size of silica aerogels and titanium containing silica
aerogels. Results from NM showed that
silica aerogels have surface fractal dimension while titanium containing silica
aerogels have mass fractal dimension. On the other hand, results from BATAN showed that both silica aerogels and
titanium containing silica aerogels have mass fractal dimension. The particle
size for silica aerogels and titanium containing silica aerogels samples
obtained by NM were 11.18 ± 0.03 and 9.19 ± 0.06 nm, respectively while the
respective values obtained from BATAN measurements were 11.78 ± 0.06 and 10.57 ± 0.07 nm.
Keywords: aerogels; particle size; small angle neutron
scattering (SANS)
ABSTRAK
Teknik serakan neutron sudut kecil (SANS) digunakan dengan meluas bagi mengkaji mikrostruktur bahan
amorfos pada julat nanometer. Dalam sistem aerogel, julat saiz 1 – 100 nm
diminati kerana unit struktur seperti liang dan zarah berada dalam julat
sebegini. Dalam eksperimen serakan, keamatan neutron terserak diukur sebagai
fungsi sudut serakan. Berbagai plot keamatan I(Q) dan vektor serakan, Q boleh
memberikan maklumat mengenai dimensi fraktal, serta saiz zarah dan klusternya.
Dalam kajian ini, kemudahan SANS di
Nuklear Malaysia (NM) dan di Badan Tenaga Atom Nasional (BATAN), Indonesia digunakan bagi menganalisis
saiz zarah dan kluster aerogel silika dan titanium mengandungi aerogel silika.
Keputusan daripada NM menunjukkan aerogel silika mempunyai
dimensi fraktal permukaan sementara titanium mengandungi aerogel silika
mempunyai dimensi fraktal jisim. Sebaliknya keputusan dari BATAN menunjukkan kedua-dua sampel mempunyai
dimensi fraktal jisim. Saiz zarah bagi aerogel silika dan titanium mengandungi
aerogel silika dari NM ialah 11.18 ±
0.03 and 9.19 ± 0.06 nm sementara dari BATAN adalah 11.78 ± 0.06 and 10.57 ± 0.07 nm.
Kata kunci: aerogel; saiz zarah; serakan neutron kecil sudut (SANS)
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*Pengarang untuk surat-menyurat; email: noorddin@mel.fs.utm.my