Mechanisms of Simultaneous Hydrogen Production and Formaldehyde Oxidation in H2O and D2O over Platinized TiO2
- authored by
- H. Belhadj, S. Hamid, P.K.J. Robertson, D.W. Bahnemann
- Abstract
The simultaneous photocatalytic degradation of formaldehyde and hydrogen evolution on platinized TiO
2 have been investigated employing different H
2O/D
2O mixtures under oxygen-free conditions using quadrupole mass spectrometery (QMS) and attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The main reaction products obtained from the photocatalytic oxidation of 20% formaldehyde were hydrogen and carbon dioxide. The ratio of evolved H
2 to CO
2 was to 2/1. The HD gas yield was found to be dependent on the solvent and was maximized in a H
2O/D
2O mixture (20%/80%). The study of the solvent isotope effect on the degradation of formaldehyde indicates that the mineralization rate of formaldehyde (CO
2) decreases considerably when the concentration of D
2O is increased. On the basis of the ATR-FTIR data, the formaldehyde in D
2O is gradually converted to deuterated formic acid during UV irradiation, which was confirmed by different band shifting. An additional FTIR band at 2050 cm
-1 assigned to CO was detected and was found to increase during UV irradiation due to the adsorption of molecular CO on Pt/TiO
2. The results of these investigations showed that the molecular hydrogen is mainly produced by the reduction of two protons originating from water and formaldehyde. A detailed mechanism for the simultaneous hydrogen production and formaldehyde oxidation in D
2O is also presented. (Chemical Equation Presented).
- Organisation(s)
-
Institute of Technical Chemistry
- Type
- Article
- Journal
- ACS catalysis
- Volume
- 7
- Pages
- 4753-4758
- No. of pages
- 6
- ISSN
- 2155-5435
- Publication date
- 07.07.2017
- Publication status
- Published
- Peer reviewed
- Yes
- ASJC Scopus subject areas
- Catalysis, General Chemistry
- Sustainable Development Goals
- SDG 7 - Affordable and Clean Energy
- Electronic version(s)
-
https://doi.org/10.1021/acscatal.7b01312 (Access:
Unknown)
