Journal
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
Volume 130, Issue 42, Pages 13885-13891Publisher
AMER CHEMICAL SOC
DOI: 10.1021/ja8034637
Keywords
-
Categories
Funding
- EPSRC [EP/F00270X/1] Funding Source: UKRI
- Engineering and Physical Sciences Research Council [EP/F00270X/1] Funding Source: researchfish
- Natural Environment Research Council [NE/C513169/1] Funding Source: researchfish
Ask authors/readers for more resources
We show for the first time that the photogenerated hole lifetime in TiO(2) is a strong determinant of the ability of TiO(2) to split water. Hole lifetimes were measured using transient absorption spectroscopy over a range of excitation intensities. The lifetimes of the holes were modulated by the use of exogenous scavengers and were also found to vary systematically with the excitation intensity. In all cases the quantum yield of oxygen production is found to be linked to the light intensity used, ranging from below 1 sun equivalent to nearly 1 sun equivalent. We also provide evidence that oxygen production requires four photons for each molecule of oxygen, which is reminiscent of the natural photosynthetic water-splitting mechanism. This in turn suggests a mechanism for oxygen production which requires four-hole chemistry, presumably via three, as yet unidentified intermediates. It is also shown that at excitation densities on the order of 1 sun, nongeminate electron-hole recombination limits the quantum yield significantly.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available