Yeni karma-metal-ortoboratlarin sentezi ve karakterizasyonu

In this study, magnesium orthoborate and novel-mixed-metal orthoborates were synthesized by high temperature solid state reaction method and the characterization of products were examined by powder X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Thermogravimetric/Differential Thermal Analysis (TG/DTA) methods.In the first part of this study, magnesium orthoborate, Mg3(BO3)2, was synthesized using different magnesium sources, MgO, MgCO3, MgSO4, by conventional ceramic method. It was found that the magnesium orthoborate with the highest purity was prepared from the MgSO4.In the second part of this study, different amounts of manganese (II) ion were doped to magnesium, cobalt and nickel orthoborate to obtain novel-mixed-metalorthoborate compounds, at the formula M3-xMnx(BO3)2 (M = Mg, Co, Ni; 0 ? x ? 0.10).All these compounds obtained were indexed in the orthorhombic crystal system and their unit cell parameters refined by Jana2006 are given as follows;For magnesium manganese orthoborates, Mg3-xMnx(BO3)2 ( 0 ? x ? 0.10),Mg2.99Mn0.01(BO3)2: a= 5.406(3), b= 8.430(4), c= 4.508(4),Mg2.95Mn0.05(BO3)2: a= 5.410(4), b= 8.436(2), c= 4.507(8),Mg2.90Mn0.1(BO3)2: a= 5.144(4), b= 8.444(3), c= 4.512(0) Å;For cobalt manganese orthoborates, Co3-xMnx(BO3)2 ( 0 ? x ? 0.10),Co2.99Mn0.01(BO3)2: a= 5.469(7), b= 8.451(2), c= 4.533(5),Co2.95Mn0.05(BO3)2: a= 5.469(9), b= 8.452(8), c= 4.533(8),Co2.90Mn0.1(BO3)2: a= 4.483(4), b= 8.476(4), c= 4.538(4) Å;For nickel manganese orthoborates, Ni3-xMnx(BO3)2 ( 0 ? x ? 0.10),Ni2.99Mn0.01(BO3)2: a = 5.397(4), b= 8.301(8), c= 4.458(9),Ni2.95Mn0.05(BO3)2: a= 5.403(6), b= 8.311(6), c= 4.463(3),Ni2.50Mn0.50(BO3)2: a= 5.405(8),b= 8.313(3), c= 4.465(2) Å.It was determined that all these compounds were found isostructural with kotoite type of borates, M3(BO3)2 (M= Mg, Ni, Co).The IR study showed that these borates have the BO3 units in planar triangles. Besides, SEM images showed that these compounds were homogeneus. It was also detected that these orthoborates prepared were thermodynamically stable in the temperature range of 20-1200 oC by TG/DTA method.Anahtar Kelimeler: Karma Metal Ortoborat, Kotoit, Boratlara Mn(II) katkılanması, XRD, FTIR, TG/DTA, SEM.