Thermal decomposition and spectral characterization of di[carbonatotetraamminecobalt(III)] sulfate trihydrate and the nature of its thermal decomposition products

• DOI: 10.1007/s10973-020-09991-3
• Publication Date: 2020-07-13T02:02:36Z
• Authors: Fernanda Paiva Fr...; Berta Barta-Holló; Vladimir M. Petru...; Istvan E. Sajó; Szilvia Klébert; Attila Farkas; Eszter Bódis; Imre Miklós Szilágyi; Rajendra P. Pawar; László Kótai
• Keywords: Photodegradation

Abstract Detailed vibrational (IR, Raman, far-IR) and thermal (TGA, TG–MS, DSC) analysis has been performed on di[κ 1 O,κ 2 O-carbonatotetraamminecobalt(III)] sulfate trihydrate, ([Co(NH 3 ) 4 CO ] SO ·3H O ( ). Its isothermic heating at 100 °C leads to formation of [Co(NH (compound UV IR studies showed that the distorted octahedral arrangement around cis-O CoN core in compound does not change during dehydration, which explains reversible water loss ability rehydrate into . Compound decomposes ~ 240 inert atmosphere giving final decomposition products, are two modifications nanosized metallic cobalt (hcp-15 nm, fcc-250 nm) CoO (55 nm). The redox reaction results N as an ammonia oxidation product. intermediate is a cobalt(II) compound, Co 1,14+δ (SO 0.86 δ = oxygen surplus due presence 2.8% Co(III) ion). same air resulted 1.25+δ 0.75 5.3% ion 3a oxidized 793 exhibits catalytic activity photodegradation Congo red. process follows pseudo-first-order kinetic k app 1.0 7.0. pH 3.4 5.25, respectively).