18 research outputs found
Polynuclear coordination precursor compounds for M3Fe5O12 garnets (M = Y, Eu, Gd and Er). Part I. Synthesis of the precursors
No full text4 = tartarate anion, C6O7H – 11 = gluconate anion � have been synthesized and characterised by elemental chemical analysis and physico-chemical measurements (IR, UV-Vis spectroscopy and magnetic determinations). The synthetic possibilities offered by the use of these new compounds as potential precursors for garnets have been suggested
JSCS–3779 Original scientific paper Synthesis of lithium ferrites from polymetallic carboxylates
No full textAbstract: Lithium ferrite was prepared by the thermal decomposition of three polynuclear complex compounds containing as ligands the anions of malic, tartaric and gluconic acid: (NH4) 2[Fe2.5Li0.5(C4H4O5) 3(OH) 4(H2O) 2]�4H2O (I), (NH4) 6[Fe2.5Li0.5(C4H4O6) 3(OH) 8]�2H2O (II) and (NH4) 2[Fe2.5Li0.5(C6H11O7) 3(OH) 7] (III). The polynuclear complex precursors were characterized by chemical analysis, IR and UV–Vis spectra, magnetic measurements and thermal analysis. The obtained lithium ferrites were characterized by XRD, scanning electron microscopy, IR spectra and magnetic measurements. The single �-Li0.5Fe2.5O4 phase was obtained by thermal decomposition of the tartarate complex annealed at 700 °C for 1 h. The magnetization value ≈ 50 emu g-1 is lower than that obtained for the bulk lithium ferrite due to the nanostructural character of the ferrite. The particle size was smaller than 100 nm
Synthesis of lithium ferrites from polymetallic carboxylates
No full textLithium ferrite was prepared by the thermal decomposition of three polynuclear complex compounds containing as ligands the anions of malic, tartaric and gluconic acid: (NH4)2[Fe2.5Li0.5(C4H4O5)3(OH)4(H2O)2]×4H2O (I), (NH4)6[Fe2.5Li0.5(C4H4O6)3(OH)8]×2H2O (II) and (NH4)2[Fe2.5Li0.5(C6H11O7)3(OH)7] (III). The polynuclear complex precursors were characterized by chemical analysis, IR and UV–Vis spectra, magnetic measurements and thermal analysis. The obtained lithium ferrites were characterized by XRD, scanning electron microscopy, IR spectra and magnetic measurements. The single α-Li0.5Fe2.5O4 phase was obtained by thermal decomposition of the tartarate complex annealed at 700 °C for 1 h. The magnetization value ≈ 50 emu g-1 is lower than that obtained for the bulk lithium ferrite due to the nanostructural character of the ferrite. The particle size was smaller than 100 nm
Thermal investigations of nickel–zinc ferrites formation from malate coordination compounds
No full textPolynuclear coordination precursors compounds for M3Fe5O12 garnets (M=Y, Eu, Gd and Er), Part I: Synthesis of the precursors
No full textPolynuclear coordination precursor compounds for M3Fe5O12 garnets (M = Y, Eu, Gd and Er).
No full textA new type of complexes compounds (NH4)6[M3Fe5(C4O5H4)6(C4O5H3)6]·16H2O (where M(III) = Y, Eu, Gd, Er), (NH4)6[M3Fe5(C4O6H4)6(C4O6H3)6]·16H2O (where M(III) = Gd, Er) and (NH4)6[M3Fe5(C6O7H10)6(C6O7H9)6]·xH2O (where M(III) = Y; x = 8; M(III) = Eu, Er; x = 22) [C4O5H42– = malate anion; C4O6H42– = tartarate anion, C6O7H11– = gluconate anion] have been synthesized and characterised by elemental chemical analysis and physico-chemical measurements (IR, UV-Vis spectroscopy and magnetic determinations). The synthetic possibilities offered by the use of these new compounds as potential precursors for garnets have been suggested
Synthesis of CuGa 2O 4 nanoparticles by precursor and self-propagating combustion methods
No full textCopper gallate spinels, CuGa 2O 4, have been synthesized by two wet chemical routes: precursor method and self-propagating combustion involving a glycine-nitrate system. All complex precursors have been characterized by chemical analysis, infrared spectroscopy (IR), ultraviolet visible spectroscopy (UV-vis), electron paramagnetic resonance spectroscopy (EPR), thermal analysis and scanning electron microscopy (SEM). The copper gallate spinel oxides have been further investigated by X-ray diffraction (XRD), SEM, IR, UV-vis, magnetic measurements and EPR. The crystallite size of the copper gallate was found about 280 Å. © 2012 Elsevier Ltd and Techna Group S.r.l
