Special features of formation of nanocrystalline BiFeO3 via the glycine-nitrate combustion method

This review analyzes and summarizes the research results for oxide material synthesis by combustion of organic-inorganic mixtures. We have outlined the range of physical and chemical factors influencing the precursor processes and the oxide material synthesis itself, as well as have shown the ways and options to control these processes and nanoscale materials' properties. We have highlighted several issues concerning the analysis methods for the resulting materials and processes. We have exemplified the practical implementation of the methods under discussion.

Section: Oxide Materials Production By Scsmentioning

confidence: 99%

Section: Oxide Materials Production By Scsmentioning

confidence: 99%

Oxide material synthesis by combustion of organic-inorganic compositions

Ostroushko¹,

Русских²

2017

“…Crystal growth can be reduced by using special synthetic methods, which include, in particular, soft chemistry methods, when synthesis proceeds at relatively low temperatures [36][37][38][39][40][41][42][43][44][45][46][47][48][52][53][54][55][56][57][58][59]. Another group of methods that includes, for example, solution combustion, self-propagating high-temperature synthesis (SHS), autocatalytic and other fast solidstate reactions, is based on the use of rapid synthesis [49][50][51][60][61][62][63][64][65][66][67][68][69][70][71]. Crystal growth can often be restricted by using nano-and microreactors, or synthesis methods that use spatial constraints [63,64,[72][73][74][75][76][77][78][79][80]…”

Section: Introductionmentioning

confidence: 99%

The minimum size of oxide nanocrystals: phenomenological thermodynamic vs crystal-chemical approaches

Almjasheva¹,

Ломанова²,

Попков³

et al. 2019

The minimum crystallite size in a group of oxides has been analyzed as a function of their synthesis conditions, critical nucleus size and the crystal structure parameters. Nanocrystals were synthesized by solution combustion, hydrothermal synthesis and heat treatment in air of the precipitated hydroxides. Aluminum and iron oxides, titania and zirconia, cobalt ferrite, AFeO 3 ferrites (A = Bi, RE), Aurivillius phases Bi m+1 Ti 3 Fe m−3 O 3m+3 (m = 3 -9), as well as solid solutions based on these phases were chosen as the objects of the study. The presence of a correlation between the crystalline oxide unit cell parameters and the synthesized crystals minimum size is shown. A conclusion was made about the impossibility to use only the thermodynamic concept of the critical nucleus for determining the minimum possible particle size of a new phase in some cases of oxide nanocrystals synthesis. The paper demonstrates a necessity to use crystal-chemical criteria that complement the methods of phenomenological thermodynamics and kinetics for determining the minimum possible particle size of the resulting crystalline oxide phases synthesized under the considered conditions.

“…The methods of synthesizing simple bismuth-containing perovskites and layered perovskite-like oxides, which make it possible to perform the synthesis of materials while varying their morphology and particle sizes within a broad range by changing technological parameters, are described, for example, in [27][28][29][30][31][32][33][34][35][36][37][38][39][40]. It is shown that irrespective of the technology, material formation begins at the melting temperature of the surface (non-autonomous) bismuth oxide-based phase, at which mass transfer in the reaction system is activated [41][42][43].…”

Section: Introductionmentioning

confidence: 99%

Formation mechanism, thermal and magnetic properties of (Bi(1-x)Sr(x))(m+1)Fe(m-3)Ti(3)O(3(m+1)-δ) (m = 4 – 7) ceramics

Ломанова¹,

Томкович²,

Уголков³

et al. 2018

Specific features of the formation of Aurivillius phases (Bi 1−x Srx) m+1 Fe m−3 Ti 3 O 3(m+1)−δ (m = 4 − 7; x = 0.0 − 0.7) with a perovskitelike block having a nanometric thickness (h) of 2-3 nm are described. It has been established that the degree of isomorphous substitution in the bismuth sublattice and thermal stability of phases tend to reduce with the increasing h. It has been demonstrated that the magnetic ions inside the perovskite-like block can have antiferromagnetic interaction exchange that influences magnetic properties of the Aurivillius phases.