Combustion method glycine

Julien, C., Letranchant, C., Lemal, M., Ziolkiewicz, S., Castro-Garcia, S., Layered LiNio 5Coo 502 compounds synthesized by a glycine-assisted combustion method for lithium batteries, J. Mater. Sci. 37,2367-2375 (2002). 

Use of the combustion method in an atmosphere of air or oxygen to prepare complex metal oxides seems obvious. In the last three to four years, a variety of oxides have been prepared using nitrate mixtures with a fuel such as glycine or urea. It seems that almost any ternary or quaternary oxide can be prepared by this method. All the superconducting cuprates have been prepared by this method, although the resulting products in fine particulate form have to be heated to an appropriate high temperature in a desired atmosphere to obtain the final cuprate [18], Table 2 lists typical materials prepared by the combustion method. 

The glycine/nitrate process (GNP) is a self-combustion method using glycine as fuel and the nitrates of metal components of the material to be synthesized as oxidant, which can prepare a high specific surface powder with single phase composition in very short time. It is especially appropriate for the fabrication of multi-component system such as doped perovskite compounds [11]. Moreover, this process is easily operated and cost-effective. 

Co-precipitation method, sol-gel method, freeze drying method, spray pyrolysis method and combustion method are usually used to prepare powders. Powders prepared by the combustion method have small size, high purity and good chemical stability. Urea, glycine, carbohydrazide, citric acid and so on were used as the fiiel in this paper. According to the previous report, Gd203 powders have a monoclinic structure when citric acid was used as the fiiel. While we used the citric acid and EDTA as combination fuel, the Gd203 powders prepared had the cubic structure in this paper. As comparison, oxalic acid co-precipitation was also used to prepare the powders. 

For the low-temperature synthesis of LaA103, Taspinar and Tas (1997) proposed a self-propagating combustion synthesis from aqueous solution containing urea and the respective nitrate salts. A pure perovskite phase was obtained at 1023 K, which is one of the lowest temperatures reported for the powder s)mthesis of LaA103 so far. Han et al. (2006) used a combustion method for the s)mthesis of Eu " -activated YAIO3 and GdA103 by redox reactions between the respective metal nitrates and glycine in a preheated furnace at 773 K. 

The glycine nitrate process is one of a general class of combustion methods for the preparation of ceramic powders. A highly viscous mass formed by evaporation of a solution of metal nitrates and glycine is ignited to produce the powder (101). Glycine, an amino acid, forms complexes with the metal ions in solution which... 

Figure 17.6 SEM micrographs of LaMnOs+s perovskites prepared by combustion method using glycine/nitrate ratios of 0.8 (a) and 0.43 (b). (Reprinted with permission from Ref. [22]. Copyright 2011, Elsevier.)...

Figure 10. XRD patterns of the LSM powders after calcination, prepared with urea (A) and glycine (B) in the combustion method...

Fig. 12.3 Micrographs of (a) inverse spinel LiNiV04 synthesized by the glycine-assisted combustion method, (b) LiMn204 spinel nanopowders prepared by combustion method using urea as a fuel...

The samarium doped cerium powder produced by the PVA method was a sub-micron powder with a high surface area. As explained in previous sections, the PVA resin was heated to a higher temperature on the hot plate to allow the explosive decomposition of the nitrates in a more contained manner. This resulted in precursor powders that were crystalline and nearly free of organic material. One should note that the surface area of the SDC is lower than that of the other SOFC materials possibly due to presintering of the particles at the combustion temperature. This process is in fact very similar to the glycine-nitrate method except that the PVA does not... 

Pure metal nanoparticles have shown exceptional catalytic properties which have motivated modem researchers to come up with innovative ideas to synthesize nanoparticles in a cost effective manner. Apart from catalysis, potential applications of metal nanoparticles ate well known in other fields such as pigments, electronic and magnetic materials, dmg deUvery etc. Here we report solution combustion synthesis method to synthesize transition metals (Ni, Cu and Co) in a single step process. Metal nitrates and glycine are used as synthesis precursors and dissolved in water to make a homogeneous aqueous solution which is combusted to produce metal nanoparticles with desired composition. 

Advantages and drawbacks are inherent to the process itself. The requested characteristics of fine ceramic powders used for electrode fabrication of anode and cathode are less strict than those of electrolyte. The hydrothermal method and glycine-nitrate combustion process (GNP) are essentially employed to prepare the nano-scale ceramic powders at INER . The solid state reaction method may be used for preparation of the mixed ceramic powders without the restrict limitations of the characteristics of particle size and surface area. 

In the sol-gel method, the nature of the complexant (fuel) is also important The sintered density and the activation energies of compacts obtained from microwave-assisted gel-combined combustion process for a series of fuels (citric acid, urea, and glycine) showed different results. This was well evidenced by determining the crystal structure, particle size, specific surface area, and morphology of nanocrystalline 8mol% yttria-stabilized zirconia (YSZ) powders [23]. 

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