Abstract
This study improved the photocatalytic activity of NaTaO3 by replacing some Na ions in the 12-coordinate sites with larger K ions. Na 1-xKxTaO3 photocatalysts of x = 0-0.2 were synthesized by the sol-gel method. K-doping at x = 0.05 resulted in rectifying the distorted perovskite NaTaO3 to a pseudo-cubic phase as well as significantly promoting the photocatalytic activity. The 180° bond angle of Ta-O-Ta in the pseudo-cubic phase may facilitate the separation of photogenerated charges for effective water splitting. Photoluminescence spectroscopic analysis confirmed that the flattened Ta-O-Ta linkage with K-doping suppresses the recombination of photogenerated charges. Further K-doping (with x > 0.05) leads to impurity formation, which bends the Ta-O-Ta linkage and creates defect states, lowering the photocatalytic activity of the K-doped NaTaO3. This study demonstrates that an appropriate ion replacement to tune the crystal structure can significantly promote electron transport in photocatalysts and thus their activity.
Original language | English |
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Pages (from-to) | 3824-3830 |
Number of pages | 7 |
Journal | Journal of Materials Chemistry |
Volume | 21 |
Issue number | 11 |
DOIs | |
Publication status | Published - 2011 Mar 21 |
All Science Journal Classification (ASJC) codes
- General Chemistry
- Materials Chemistry