Study of the electrochemical oxidation mechanism of formaldehyde on gold electrode in alkaline solution

The oxidation of formaldehyde in alkaline solution was studied by in situ rapid-scan time-resolved IR spectroelectrochemistry (RS-TR-FTIRS) method. In the potential range between −0.7 V and 0.2 V, the gem-diol anions were oxidized (according to the 2765 cm−1 of υHO and 1034 cm−1 of υCO downward IR bands) and the formate ions appeared (according to the 1588, 1357 cm−1 of the asymmetric and symmetric υOCO and 1380 cm−1 of δCH upward IR bands) in aqueous solution. It was also confirmed that gem-diol anion was oxidized (according to the 2026, 1034 cm−1 downward IR bands) to formate ions (according to the 1595, 1357, 1380 cm−1 upward IR bands) and water (according to the 3427 cm−1 of υHO upward IR band) in heavy water solution. The results illustrated that formaldehyde formed gem-diol anion in alkaline solution and was absorbed on the electrode surface; then gem-diol anion was oxidized to formate ions and water.

The formaldehyde molecule formed gem-diol anion in alkaline solution and was absorbed on the electrode surface; then gem-diol anion was oxidized to formate ions and water.Figure optionsDownload as PowerPoint slide