Vibrational EELS and DFT study of propionic acid and pyruvic acid on Ni(100): Effects of keto group substitution on room-temperature adsorption and thermal chemistry

Heterogeneous chemistry of monocarboxylic acids on α-Al<sub>2</sub>O<sub>3</sub> at different relative humidities

“…Due to CH 2 and CH 3 group of CH 3 CH 2 COOH, more bands are appeared at the region in 1200-1500 cm −1 . The peaks at 1259, 1303, 1382, 1420, and 1475 cm −1 are assigned to the vibrational features of CH 3 and CH 2 groups (Yang et al, 2006), respectively. The assignment of the other bands are shown in Table 1S.…”

“…There may exist three coordination modes: a monodentate mode where one carboxylate oxygen is coordinated to a surface Al atom (model I), a bidentate mode involving a deprotonated molecule where the two carboxylate oxygens are bonded to the same Al atom (model II), and a bridging mode similar to above but where the two oxygens of carboxylate are coordinated to two different surface Al atoms (model III) (Alcock et al, 1976;Dobson and McQuillan, 1999;Mehrotra and Bohra, 1983;Popova et al, 2007). In recent years, in addition to the conventional spectroscopic techniques, quantum chemistry has been applied to state of adsorbed species and the structure of the adsorption sites in gas adsorption on particles (Baltrusaitis et al, 2007;Gao et al, 2008;Grassian, 2008;Yang et al, 2006). To understand the exact structures of adsorbed carboxylates and assignment of carboxylate species on the particles surface clearly, we tried to compare the adsorption energies and frequencies of the IR bands of carboxylates adsorbed on the respective sites with the values evaluated from the calculation method utilizing the DFT method.…”

Heterogeneous chemistry of monocarboxylic acids on α-Al<sub>2</sub>O<sub>3</sub> at ambient condition

“…In comparison with the vibrational features of the liquidphase (Jakobsen et al, 1971) and gas-phase CH 3 CH 2 COOH, the absence of the ν(OH) and ν(C=O) indicates that the physisorbed propionic acid is inexistent. (Yang et al, 2006). As seen from Fig.…”

“…In recent years, in addition to the conventional spectroscopic techniques, quantum 5 chemistry has been applied to state of adsorbed species and the structure of the adsorption sites in gas adsorption on particles (Baltrusaitis et al, 2007;Gao et al, 2008;Yang et al, 2006). To understand the exact structures of adsorbed carboxylates and assignment of carboxylate species on the particles surface clearly, we tried to compare the adsorption energies and frequencies of the IR bands of carboxy-10 lates adsorbed on the respective sites with the values evaluated from the calculation method utilizing the DFT method.…”

Interaction of functionalized Ga2O3 NW-based room temperature gas sensors with different hydrocarbons

“…Simple carboxylic acids, such as formic, acetic and valeric acids, adsorb strongly on different materials including oxides [3][4][5][6][7][8][9]. We have used this mechanism to functionalize Ga 2 O 3 nanowires (NWs), incorporated into gas sensing devices, with pyruvic acid (CH 3 (C O)CO 2 H, PA) by simple room-temperature vapor transport [10].…”