TY - JOUR

T1 - Effect of H2O and O2 on the adsorption and degradation of acetaldehyde on anatase surfaces—An in situ ATR-FTIR study

AU - Melchers, Stephanie

AU - Schneider, Jenny

AU - Emeline, Alexei V.

AU - Bahnemann, Detlef W.

PY - 2018/10/1

Y1 - 2018/10/1

N2 - The effect of H2O and O2 on the adsorption and degradation of gaseous acetaldehyde on the anatase TiO2 surface has been studied, in the dark and upon UV illumination, at ambient temperatures. The processes occurring at the surface have been elucidated by means of in situ ATR–FTIR (Attenuated Total Reflection—Fourier Transform Infrared) spectroscopy, while gas detectors allowed the analysis of the adducts and products in the gas phase. In the dark and under dry conditions acetaldehyde reacts independently of the atmosphere, upon aldol condensation to crotonaldehyde. However, under humid conditions, this reaction was prevented due to the replacement of the adsorbed acetaldehyde molecules, by water molecules. Upon UV illumination under oxygenic conditions, acetaldehyde was decomposed to acetate and formate. Under an N2 atmosphere, the formation of acetate and formate was observed during the first hour of illumination, until all adsorbed oxygen had been consumed. In the absence of molecular oxygen acetate, methane, and CO2 were detected, the formation of which most likely involved the participation of the bridging O atoms, within the TiO2 lattice.

AB - The effect of H2O and O2 on the adsorption and degradation of gaseous acetaldehyde on the anatase TiO2 surface has been studied, in the dark and upon UV illumination, at ambient temperatures. The processes occurring at the surface have been elucidated by means of in situ ATR–FTIR (Attenuated Total Reflection—Fourier Transform Infrared) spectroscopy, while gas detectors allowed the analysis of the adducts and products in the gas phase. In the dark and under dry conditions acetaldehyde reacts independently of the atmosphere, upon aldol condensation to crotonaldehyde. However, under humid conditions, this reaction was prevented due to the replacement of the adsorbed acetaldehyde molecules, by water molecules. Upon UV illumination under oxygenic conditions, acetaldehyde was decomposed to acetate and formate. Under an N2 atmosphere, the formation of acetate and formate was observed during the first hour of illumination, until all adsorbed oxygen had been consumed. In the absence of molecular oxygen acetate, methane, and CO2 were detected, the formation of which most likely involved the participation of the bridging O atoms, within the TiO2 lattice.

KW - Acetaldehyde

KW - Adsorption

KW - Anatase

KW - ATR-FTIR

KW - Degradation

KW - Oxygen

KW - TiO

KW - adsorption

KW - MECHANISM

KW - PHOTOCATALYTIC OXIDATION

KW - ACETONE

KW - degradation

KW - anatase

KW - ACETIC-ACID

KW - CROTONALDEHYDE

KW - GAS-PHASE

KW - CONDENSATION

KW - ETHANOL

KW - acetaldehyde

KW - oxygen

KW - TiO2

KW - TIO2

KW - PHOTOOXIDATION

UR - http://www.scopus.com/inward/record.url?scp=85054128548&partnerID=8YFLogxK

UR - http://www.mdpi.com/2073-4344/8/10/417

UR - http://www.mendeley.com/research/effect-h2o-o2-adsorption-degradation-acetaldehyde-anatase-surfacesan-situ-atrftir-study

U2 - 10.3390/catal8100417

DO - 10.3390/catal8100417

M3 - Article

AN - SCOPUS:85054128548

VL - 8

JO - Catalysts

JF - Catalysts

SN - 2073-4344

IS - 10

M1 - 417

ER -