Avoiding Binary Compounds as Reaction Intermediates in Solid State Reactions

Abstract

Preparing new ternary compounds via traditional high temperature synthesis techniques is essentially limited to ternary compounds that are thermodynamically more stable than any mixture of binary compounds because binary compounds typically form as reaction intermediates. By using a precursor having elemental layers thinner than a critical thickness, it is possible to decrease diffusion times such that the layers interdiffuse before nucleation of binary compounds occurs at reacting interfaces. To nucleate the ternary compounds CuInSe 2 and CuCr 2 Se 4 directly from amorphous reaction intermediates, however, it is shown to be necessary to use the order of the elemental layers to control of the order of mixing of the elemental layers. Controlling layer thickness and layer sequence is a general strategy for avoiding binary compounds as reaction intermediates, providing a general approach to preparing kinetically stable ternary compounds.

Structural Evolution of Iron Antimonides from Amorphous Precursors to Crystalline Products Studied by Total Scattering Techniques

“…21 In this case, the slow diffusion rates become a synthetic advantage and can be used to help control the formation of kinetic products. 22 Particularly exciting is the possibility of "designing precursors" to yield desired products by controlling the deposition process. To realize the full potential of this method, it is essential to be able to characterize in detail not only the reaction products but also the amorphous precursors and the reaction pathways to the resulting product.…”

Characterization of Cr-rich Cr-Sb multilayer films: Syntheses of a new metastable phase using modulated elemental reactants

“…The MER approach has been used successfully for the synthesis of new, metastable compounds [15][16][17][18][19][20]. This technique was also previously used to explore metastable transition metal antimonides Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/jssc as well as various other binary and ternary compounds based on Cr-Sb, Fe-Sb, Ru-Sb, Ni-Sb or Cu-Cr-Se [21][22][23][24][25][26][27][28][29][30], making this a promising approach to the targeted compound.…”

Effects of processing parameters on the morphology, structure, and magnetic properties of Cu1−xFexCr2Se4 nanoparticles synthesized with chemical methods

“…CuCr 2 Se 4 characterized by the Curie temperature, T c , near 430 K [2][3][4][5] and magnetic moment M s of 5.07 µ B /mole at 0 K [6], displays a large magneto-optical Kerr effect (KE) in the near infrared spectral region [7][8][9] and has highly spin-polarized characteristics [8,10]. So, it can be considered as a perspective material for spintronics.…”