Direct Synthesis of Iron Oxide Nanopowders by the Combustion Approach:  Reaction Mechanism and Properties

Abstract

Solution combustion synthesis of different oxides involves a self-sustained reaction between an oxidizer (e.g., metal nitrate) and a fuel (e.g., glycine, hydrazine). The mechanism of synthesis for three major iron oxide phases, i.e., R-and γ-Fe 2 O 3 and Fe 3 O 4 , using the combustion approach and a combination of simple precursors such as iron nitrate and oxalate, as well as different fuels, is investigated. Based on the obtained fundamental knowledge, for the first time in the literature, the above powders with well-crystalline structures and surface areas in the range 50-175 m 2 /g are produced using a single approach while simultaneously avoiding additional calcination procedures. It is also shown that utilizing complex fuels and complex oxidizers is an attractive methodology to control the product composition and properties.

Frequency and Temperature Dependent Dielectric Response of Fe₃O₄ Nano-crytallites

“…Further increase in the peaks corresponding to the Fe 3 O 4 and decrease in the peaks related to γ-Fe 2 O 3 were observed when the fuel concentration was further increased, keeping MN to CA ratio of 1:3. The results are quite in agreement with some previous reports [14].…”

Synthesis of thin-multiwalled carbon nanotubes by Fe-Mo/MgO catalyst using sol-gel method

“…To prepare a homogeneous and efficient catalyst, it is desirable to fabricate well dispersed catalyst nanoparticles without agglomeration on the support materials [7][8][9]. However, there are two major problems for catalyst fabrication using a conventional combustion process: (i) difficulty of the process and poor reproducibility for the fabrication of homogeneous catalyst material due to a very fast and violent combustion process [10], and (ii) severe agglomeration of catalyst nanoparticles during the sintering process at the time of CNT growth.…”

Hierarchical Nanoceramics for Industrial Process Sensors

“…Metal nitrate salts have generally been used as the oxidizers in such reactions. Fuel choices have included urea [Kingsley 1988, Sousa 1999, Mimani 2001, Civera 2003, Basu 2004, citric acid [Basu 2004, Schafer 1997, Roy 1999, Deshpande 2004 , hydrazine , Deshpande 2004, Ekambaram 1995, polyvinyl alcohol [Ma 2006], hexamethylenetetramine [Mimani 2001, Nagaveni 2004, oxalyldihydrazide [Mimani 2001, Nagaveni 2004, Aruna 1998] and others. Of specific interest to this study, ethylene glycol [Dasgupta 2001MatSci&Eng, Dasguputa 2002SSI, Chen 2006MatLett, Chen 2006 MatSci&Eng] has recently been used as an ACS fuel, as well as in other novel powder synthesis techniques [Bonet 1999, Uekawa 2002.…”

“…Of specific interest to this study, ethylene glycol [Dasgupta 2001MatSci&Eng, Dasguputa 2002SSI, Chen 2006MatLett, Chen 2006 MatSci&Eng] has recently been used as an ACS fuel, as well as in other novel powder synthesis techniques [Bonet 1999, Uekawa 2002. The most commonly used fuel for ACS is glycine [Mimani 2001, Deshpande 2004, Nagaveni 2004MRB, Purohit JNucMatls 2001, Peng 2002, Erri 2004, Mukasyan 2007, which has been used extensively to produce perovskite oxides [Chick 1990, Basu 2004, Yang 2000, Mukasyan 2001, Wang 2006, Striker 2007, Nair 2008.…”