“…Upon increasing temperature to 150 °C, we observed the characteristic bands of α-keto in pyruvate (1795 cm -1 and 1651 cm -1 ), 57] together with a red-shifted COO stretch at 1597 cm -1 . 55,62 The in situ DRIFTS were also reflected the adsorption and dissociation of ethyl lactate on V 2 O 5 /TiO 2 surface in the presence of oxygen. Due to the formation of pyruvate species, the position of carbonyl ν (C=O) were shifted to 1746 cm -1 , 62 as compared to the ν (C=O) of ethyl lactate at 1730 cm -1 ; The peaks at 1141 cm -1 (C-O belongs to model (a) and (b)) also started to weakened at 150 °C, accompanying the characteristic peaks of pyruvate; while the characteristic peaks of model (c) were unchanged.…”