Çeşitli anorganik fosfatların, boratların ve borfosfatların sentezi ve yapısal karakterizasyonu

This thesis covers the preparation and characterization of some novel compounds namely magnesium transition metal borates, lithium lanthanide oxyphosphates, lithium sodium lanthanide oxyphosphates, rare earth oxyapatites and lanthanide borate phosphates. Solid state method was employed for the synthesis of the desired materials. The characterization of the products was investigated by X-ray Powder Diffraction (XRPD), Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM) and Thermogravimetric Analysis-Differential Thermal Analysis (TG/DTA) methods.In the first part of this thesis, MgNi2(BO3)2, MgCo2(BO3)2, Mg2Ni(BO3)2 and Mg2Co(BO3)2 compounds were prepared through the following solid state reactions at 900oC for 48h.2M(NO3)2 6.H2O(s)+ MgO(s)+2H3BO3(s)? MgM2(BO3)2(s) + 4NO2(g)+15H2O(g)+ O2(g)(M: Ni, Co)M(NO3)2.6H2O(s)+2MgO(s)+2H3BO3(s)? Mg2M(BO3)2(s)+2NO2(g)+9H2O(g)+1/2 O2(g)(M: Ni, Co)It was found that all these compounds crystallized in the orthorhombic system and isostructural with the kotoite type of compounds, M3(BO3)2 (M: Mg, Ni, Co). It was also detected that these compounds were thermodynamically stable with 20-1000oC using thermal analysis technique.In the second part, the synthesis of new oxyphosphates of the type Li2LnOPO4 (Ln: Nd, Gd, Dy), which were not reported before have been done through the following solid state reactions at 1000oC.Ln2O3(s) + 2Li2CO3(s) + 2(NH4)2HPO4(s) ? 2Li2LnOPO4(s) +4NH3(g) +2CO2(g) +3H2O(g)Examination of the X-ray powder diffraction data and Infrared spectra of the products showed the existence of Li2NdOPO4, Li2GdOPO4, Li2DyOPO4 compounds which have an orthorhombic crystal structures with the refined unit cell parameters of a=14.865(1), b=10.734(2), c=13.231(1); a=14.686(3), b=10.634(5) c=13.047(9); a=14.554(1), b=10.589(8), c= 12.926(2) Å, respectively.In the third part of this study, LiNaNdOPO4, LiNaGdOPO4, LiNaDyOPO4, have also been prepared and indexed in orthorhombic system with the refined unit cell parameters a=14.903(8), b=10.861(3), c=13.247(1); a =14.745(0), b=10.651(6), c=13.096(8); a= 14.622(2), b=10.581(0), c= 13.018(2) Å, respectively. The thermal analysis (TG/DTA) of the compounds, Li2LnOPO4 and LiNaLnOPO4 (Ln: Nd, Gd, Dy) showed that all these compounds were stable up to1100oC.In the fourth part of this study were investigated using different rare earths to obtain Ca8Ln2(PO4)6O2 (Ln: Nd, Gd, Dy) the solid state reactions of Ln2O3 with CaHPO4 and CaCO3 (ratio:1:6:2) at different temperatures.In the last part, the attempt to prepare rare earth borate phosphates, Ln2O3, (Ln:Nd, Gd, Dy) B2O3 and (NH4)2HPO4 were done through the solid state reactions of 2Ln2O3 + B2O3+ 2(NH4)2HPO4 ? 2Ln2(BO3)(PO4) + 4NH3 + 3H2O