Infrared spectroscopic evidence for the formation of carbonite CO 2 2− ions in CO interaction with basic oxide surfaces

Surface Properties of Hydrotalcite-Based Zn(Mg)Al Oxides and Their Catalytic Activity in Aldol Condensation of Furfural with Acetone

“…From the above observations, band at 2176 (shifted to 2166) cm –1 was ascribed to the carbonyl species with coordinatively unsaturated Mg 2+ ions and band at 2196 (shifted to 2177) cm –1 to carbonyls with Zn 2+ ions. On the basis of the missing bands at 2245–2200 cm –1 and variation of the intensity of bands at 2166 and 2177 cm –1 with Mg and Zn content, respectively, no interaction of CO with unsaturated Al 3+ is supposed. − Additionally, bands of the reactive CO adsorption in the region 1485–1135 cm –1 , , mirroring presence of carbonite-like anions ( CO ) n 2– , were not observed. The absence of bands from stable carbonite-like structures, characteristic for MgO and CaO with the highly basic O 2– , supports the carbonyl band assignment above.…”

Influence of phosphonation and phosphation on surface acid–base and morphological properties of CaO as investigated by in situ FTIR spectroscopy and electron microscopy

“…Earlier studies of the adsorption of CO on CaO at room temperature did not show the formation of carbonyl species [25][26][27]. When CO adsorption was carried out at low temperature, three carbonyl bands at 2163, 2155, and 2145 cm −1 were detected [26], which were eroded upon evacuation even at 80 K. A band was observed at 2176 cm −1 when CO was adsorbed onto Ca/SiO 2 [28], which was unstable toward evacuation.…”

Infrared Study of Ozone Adsorption on CaO

“…Noteworthy is that although the band of CaO surface hydroxyls is insensitive to adsorption of bases, it completely disappears after adsorption of SO 2 with the simultaneous appearance of a broad absorption feature shifted to lower wavenumbers by about 160 cm -1 …”

“…Interaction of CO 2 with basic surface hydroxyl groups is known to lead to formation of bicarbonate HCO 3 - ions, while interaction with the surface oxygen ions yields different kinds of carbonate ions . Similarly, adsorption of SO 2 leads to bisulfite and sulfite formation. , Stronger basic sites appear on the CaO surface after its activation at 973 K, as shown after adsorption of CO by the appearance of “carbonite” CO 2 2- ions. , …”