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arXiv · 1612.07835

Influence of Defects on Photoconductivity and Photocatalytic Activity of Nitrogen-Doped Titania

A. A. Minnekhanov·N. T. Le·E. A. Konstantinova·P. K. Kashkarov
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Abstract

Samples of nitrogen-doped titanium dioxide (anatase, $0.2 \leq N \leq 1.0~wt\%$) prepared by the sol-gel method were investigated using X-band EPR spectroscopy, photoconductivity and photocatalysis measurements. $N\bullet$ and $NO\bullet$ paramagnetic defects in N-TiO2 have been observed; their concentrations and spin-Hamiltonian parameters were calculated. An increase both in the rate of the generation of free charge carriers and in the rate of photocatalysis was found in N-TiO2 in contrast with non-doped titania under visible light. The correlation of the density of the observed radicals with the photoconductivity and photocatalysis data is discussed.

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A. A. Minnekhanov, N. T. Le, E. A. Konstantinova, P. K. Kashkarov. 2017-04-17. Influence of Defects on Photoconductivity and Photocatalytic Activity of Nitrogen-Doped Titania. https://doi.org/10.1007/s00723-017-0870-4

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