Next Article in Journal
Durability of Starch Based Biodegradable Plastics Reinforced with Manila Hemp Fibers
Next Article in Special Issue
Sol-Gel Entrapped Levonorgestrel Antibodies: Activity and Structural Changes as a Function of Different Polymer Formats
Previous Article in Journal
A Review of Domain Modelling and Domain Imaging Techniques in Ferroelectric Crystals
Previous Article in Special Issue
Sol-Gel Synthesis of Non-Silica Monolithic Materials
Materials 2011, 4(2), 448-456; doi:10.3390/ma4020448
Article

Iron Oxide Silica Derived from Sol-Gel Synthesis

1
, 1
, 2
 and 1,*
Received: 28 December 2010; in revised form: 31 January 2011 / Accepted: 16 February 2011 / Published: 17 February 2011
(This article belongs to the Special Issue Sol-Gel Technique)
Download PDF [501 KB, uploaded 17 February 2011]
Abstract: In this work we investigate the effect of iron oxide embedded in silica matrices as a function of Fe/Si molar ratio and sol pH. To achieve homogeneous dispersion of iron oxide particles, iron nitrate nonahydrate was dissolved in hydrogen peroxide and was mixed with tetraethyl orthosilicate and ethanol in a sol-gel synthesis method. Increasing the calcination temperature led to a reduction in surface area, although the average pore radius remained almost constant at about 10 Å, independent of the Fe/Si molar ratio or sol pH. Hence, the densification of the matrix was accompanied by similar reduction in pore volume. However, calcination at 700 °C resulted in samples with similar surface area though the iron oxide content increased from 5% to 50% Fe/Si molar ratio. As metal oxide particles have lower surface area than polymeric silica structures, these results strongly suggest that the iron oxides opposed the silica structure collapse. The effect of sol pH was found to be less significant than the Fe/Si molar ratio in the formation of molecular sieve structures derived from iron oxide silica.
Keywords: iron oxide; silica network; molecular sieve structures iron oxide; silica network; molecular sieve structures
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Darmawan, A.; Smart, S.; Julbe, A.; Diniz da Costa, J.C. Iron Oxide Silica Derived from Sol-Gel Synthesis. Materials 2011, 4, 448-456.

AMA Style

Darmawan A, Smart S, Julbe A, Diniz da Costa JC. Iron Oxide Silica Derived from Sol-Gel Synthesis. Materials. 2011; 4(2):448-456.

Chicago/Turabian Style

Darmawan, Adi; Smart, Simon; Julbe, Anne; Diniz da Costa, João Carlos. 2011. "Iron Oxide Silica Derived from Sol-Gel Synthesis." Materials 4, no. 2: 448-456.


Materials EISSN 1996-1944 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert