The effect of light intensity and temperature on photocatalytic water splitting

Bell, Stuart James (2011) The effect of light intensity and temperature on photocatalytic water splitting. PhD thesis, Queensland University of Technology.

Abstract

Photocatalytic water splitting is a process which could potentially lead to commercially viable solar hydrogen production. This thesis uses an engineering perspective to investigate the technology. The effect of light intensity and temperature on photocatalytic water splitting was examined to evaluate the prospect of using solar concentration to increase the feasibility of the process.

P25 TiO2 films deposited on conducting glass were used as photocatalyst electrodes and coupled with platinum electrodes which were also deposited on conducting glass. These films were used to form a photocatalysis cell and illuminated with a Xenon arc lamp to simulate solar light at intensities up to 50 suns. They were also tested at temperatures between 20°C and 100°C.

The reaction demonstrated a sub-linear relationship with intensity. Photocurrent was proportional to intensity with an exponential value of 0.627. Increasing temperature resulted in an exponential relationship. This proved to follow an Arrhenius relationship with an activation energy of 10.3 kJ mol-1 and a pre-exponential factor of approximately 8.7×103.

These results then formed the basis of a mathematical model which extrapolated beyond the range of the experimental tests. This model shows that the loss of efficiency from performing the reaction under high light intensity is offset by the increased reaction rate and efficiency from the associated temperature increase. This is an important finding for photocatalytic water splitting. It will direct future research in system design and materials research and may provide an avenue for the commercialisation of this technology.

Impact and interest:

Search Google Scholar™

Citation counts are sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

Full-text downloads:

2,625 since deposited on 18 Jun 2012
261 in the past twelve months

Full-text downloads displays the total number of times this work’s files (e.g., a PDF) have been downloaded from QUT ePrints as well as the number of downloads in the previous 365 days. The count includes downloads for all files if a work has more than one.

ID Code: 50960
Item Type: QUT Thesis (PhD)
Supervisor: Bell, John & Will, Geoffrey
Keywords: photocatalysis, photosynthesis, water splitting, solar, solar hydrogen, energy conversion, hydrogen, hydrogen generation, titanium dioxide, titania, iron oxide, hematite, light intensity, temperature, reactor design
Divisions: Past > QUT Faculties & Divisions > Faculty of Built Environment and Engineering
Institution: Queensland University of Technology
Deposited On: 18 Jun 2012 07:00
Last Modified: 21 Jun 2017 14:46

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page