abstract
In this study, anatase samples enclosed by the majority of three different crystal facets {0 0 1}, {1 0 0}, and {1 0 1} were successfully synthesized. These materials were further studied toward photocatalytic degradation of phenol and toluene as model organic pollutants in water and gas phases. The obtained results were analyzed concerning their surface structure, reaction type, and surface development. Moreover, the regression model was created to find the correlation between the possible predictors and the photodegradation rate constants (k). From the studied factors, the trapping energy of charge carriers at the surface was found to be the most significant one, exponentially affecting the observed k. This resulted in the overall per- surface activity between the samples being in the order {1 0 1} > {1 0 0} > {0 0 1}. Further introduction of the surface energy (E-surf) to the regression model and the number of possible trapping centers per number of pollutant's molecules (n(trap).n(-1)) improved the model accuracy, simultaneously showing the dependence on the reaction type. In the case of phenol photocatalytic degradation, the best accuracy was observed for the model including E-surf.(n(trap).n(-1))(1/2) relation, while for the toluene degradation, it included E-surf(2) and the S.n(-1) ratio, where S is the simple surface area. Concerning different surface features which influence photocatalytic performance and are commonly discussed in the literature, the results presented in this study suggest that trapping is of particular importance.
keywords
ANATASE TIO2 NANOSHEETS; EXPOSED 001 FACETS; CHARGE-CARRIER DYNAMICS; QUANTUM EFFICIENCY; ELECTRON-TRANSFER; HETEROGENEOUS PHOTOCATALYSIS; HYDROGEN EVOLUTION; HOLE MIGRATION; WATER; NANOCRYSTALS
subject category
Chemistry; Science & Technology - Other Topics; Materials Science
authors
Dudziak, S; Kowalkinska, M; Karczewski, J; Pisarek, M; Gouveia, JD; Gomes, JRB; Zielinska-Jurek, A
our authors
José Daniel Lago da Silva Neves Gouveia
Assistant Researcher
José R. B. Gomes
Principal Researcheracknowledgements
? ACKNOWLEDGMENTS The research was financially supported by the Polish National Science Centre (grant no. NCN 2018/30/E/ST5/00845) . S.D. is grateful for the financial support from the Gdansk University of Technology (program POWR.03.05.00 - 00- Z044/17) .