Synthesis and Thermal Decomposition Kinetics of Two Dy(III) Complexes with Benzoate Derivative and 2,2′-Bipyridine as Co-ligands

Two Dy(III) complexes with benzoate derivative and 2,2'-bipyridine ligands, [Dy(2,4-DCIBA)(3)bipyl](2) and [Dy(o-MOBA)(3)bipy](2).4H(2)O (2.4-DCIBA=2,4-dichlorobenzoate; o-MOBA=o-methoxybenzoate, bipy 2,2'-bipyridine), were prepared and characterized by elemental analysis. infrared spectra, ultraviolet spectra and thermogravimetry and differential thermogravimetry techniques. The thermal decomposition behavior of the two complexes under a static air atmosphere was discussed by thermogravimetry, differential thermogravimetry and infrared spectral techniques. The non-isothermal kinetics were investigated by using a double equal-double step method, a non-linear isoconversional integral method and a Starink method The mechanism functions of the first decomposition step for [Dy(2,4-DGBA)(3)bipy](2) and the second decomposition step for [Dy(o-MOBA)(3)bipy](2).4H(2)O were de termined. Meanwhile, the thermodynamic parameters (Delta H-double dagger, Delta G(double dagger), and Delta S-double dagger and AS') and kinetic parameters (activation energy E and the pre-exponential factor A) for the two complexes were also calculated.