Thermal analysis of cis-(dithiocyanato)(1,10-phenanthroline-5,6-dione)(4,4'-dicarboxy-2,2'-bipyridyl)ruthenium(II) photosensitizer

Thermal behavior of [cis-(dithiocyanato)(1,10-phenanthroline-5,6-dione)(4,4'-dicarboxy-2,2'-bipyridyl)ruthenium(II)], cis-[Ru(L1)(L2)(NCS)(2)] (where the ligands were L1 = 1,10-Phenanthroline-5,6-dione, L2 = 4,4'-dicarboxy-2,2'-bipyridyl) was investigated by DTA/TG/DTG measurements under inert atmosphere in the temperature range of 298-1473 K as well as by XRD analysis of the final product. After making detailed analysis and comparison of thermogravimetrical and MS measurements of ruthenium complex, the decomposition mechanism of that complex was suggested. The values of activation energy and reaction order of the thermal decompositions were calculated by Ozawa Non-isothermal Method for all decomposition stages. The calculated activation energies vary in between 32 and 49 kJ mol(-1).