Studies on the Chemistry of [Cd(NH₃)₄](MnO₄)₂. A Low Temperature Synthesis Route of the CdMn₂O_4+x Type NO_x and CH₃SH Sensor Precursors

Abstract

Tetraamminecadmium(II)] bis(permanganate) (1) was prepared and its crystal structure was elucidated with XRD-Rietveld refinement and vibrational spectroscopic methods. Compound 1 has a cubic lattice consisting of a 3D hydrogen-bonded network built as four by four distorted tetrahedral blocks of [Cd(NH 3 ) 4 ] 2+ cations and MnO 4 anions, respectively. The other four permanganate ions are located in a crystallographically different environment, placed in the cavities formed by the attachment of the building blocks. A low-temperature (≈100°C) solid phase quasi-intramolecular redox reaction producing ammonium nitrate and amorphous CdMn 2 O 4 could be established. Neither solid phase nor aqueous solution phase thermal deammoniation of compound

Capturing Manganese Oxide Intermediates in Electrochemical Water Oxidation at Neutral pH by In Situ Raman Spectroscopy

“…These changes could be attributed to the local pH change in the anode during OER, resulting in an increase in the amount of HCO 3 − near the electrocatalyst film. Moreover, the evolution of the two peaks at 836 and 910 cm −1 indicated the formation of soluble MnO 4 − species corresponding to ν s (MnO 4 ) and ν as (MnO 4 ), which are commonly observed for Mn‐based electrocatalysts [79, 80] …”

Thermal analysis of solvatomorphic decakis (dimethylammonium) dihydrogendodecatungstate hydrates

“…Since in our compounds there are strongly reducing cations and oxidizing anions, one can expect a thermally induced redox reaction between them. The occurrence of such kind of redox reactions within one compound having oxidizing and reducing components is well documented in the literature [11][12][13][14][15][16][17]. Since in inert atmosphere the decomposition steps are endothermic, one can conclude that the energy required for elimination of water and dimethylamine as well as the disruption of the lattice exceeds the exothermicity of the redox interaction.…”

Capturing Manganese Oxide Intermediates in Electrochemical Water Oxidation at Neutral pH by In Situ Raman Spectroscopy

“…À species corresponding to n s (MnO 4 )a nd n as (MnO 4 ), which are commonly observed for Mn-based electrocatalysts. [79,80] Interestingly,aprominent spectral change was observed in the region of 700 to 800 cm À1 ,inwhich the vibration bands of high-valent Mn-oxo moieties are generally observed. [46][47][48][49][50][51][52][53][54] Notably,u pon increasing the applied potential, an ew broad peak centered at 760 cm À1 appeared, which is indicated by the red dotted area in Figure 3a.T he peak at 760 cm À1 was confirmed multiple times,p roducing consistent and reliable results (Supporting Information, Figure S5).…”