Introduction:
Metal oxide Nanoparticles have certain industrial and technological
properties that include optical, magnetic, electrical, catalytic,
mechanical strength, thermal stability and chemical properties. The
production of metal oxide nanoparticles is carried out using a number of
chemical methods, which include sol-gel, reduction-oxidation,
hydrothermal hydroxide oxidation, and metal salts decomposition methods.
Time efficiency, production cost, ability to operate continuously, and
production rate are the parameters that have been considered in order to
choose the best synthesis method for a specific application. Solution
combustion synthesis (SCS) or sol-gel auto-combustion method appears to
be a promising method due to low production cost, because it requires
low-cost precursor materials and equipment. It’s feasible to fabricate a
wide range of nanoparticles and metal oxides, and more efficiently
compared to some other methods [1]–[5].
The perovskite oxides are mixed metal oxides with the general formula of
ABO3, where A is larger cation usually an alkaline-earth
or rare-earth metal cation and B is the smaller cation, usually, a
transition-metal cation (e.g., Mn, Co, Fe, Ni,) surrounded by six oxygen
atoms in an octahedral coordination [6]. However, perovskite oxides,
LaMO3, in which M is a transition-metal containing Co,
Fe, Ni, have been used in a variety of applications, including gas
sensors (CO, propane and ethanol sensing) as nanostructures’ film,
hollow spheres and mesoporous nanowires, nanoparticles, porous and
fibrous structures [7]–[11], photocatalytic reduction of
CO2 with visible light, electronic devices,
electrochemical systems, solid oxide fuel cell, solar cells, and
catalysts [11]–[17]. Different methods have been uses to
synthesize and develop perovskite phase of LaCoO3 as
nanoparticles and nanowires, over the years; these include thermal
decomposition, hydrothermal, microwave-assisted coprecipitation,
co-precipitation, sol-gel, and combustion methods [10],
[17]–[22].
The purpose of this research is to synthesize nanoparticles of
LaCoO3 perovskite in a single step by combining the
sol-gel and auto-combustion steps. Investigation of the influence of
fuel ratio and different fuel on nanoparticle characteristics has been
done. These particles can be used as a catalyst in the decomposition of
nitrogen oxide gases (NOx).