Synthesis and photocatalytic activity of N-doped NaTaO3 compounds calcined at low temperature

Control of nitrogen doping in NaTaO3 synthesized by hydrothermal reaction and chemical state of nitrogen

“…Crystal sizes estimated using 2θ = 22.8° and surface areas of the samples decreased with increasing concentration of NaOH, corresponding to the results of SEM images (Table S1). Although the ion radius of nitrogen (0.171 nm) is larger than that of oxygen (0.132 nm), nitrogen doping in NaTaO 3 did not show significant structural changes. The concentration of the doped nitrogen would be too low to influence the crystal structure in all samples as discussed below.…”

“…(Table S1). Although the ion radius of nitrogen (0.171 nm) is larger than that of oxygen (0.132 nm), 9 As already noted by Kanhere et al, appearance of the NaTaO 3 and Na 2 Ta 2 O 6 is sensitive to the concentration of NaOH in aqueous solution for hydrothermal reaction. 13 They claimed that the appearance of Na 2 Ta 2 O 6 crystal phase became appreciable when decreasing the NaOH concentration in the aqueous solution.…”

“…However, the relationship between the amount of nitrogen doping and photocatalytic activity was not clear because synthesized nitrogen-doped NaTaO 3 was not a single phase. 7 Although Wang 8 and Liu 9 succeeded in nitrogen doping into NaTaO 3 by thermal treatment of NaTaO 3 in NH 3 atmosphere, high concentration nitrogen doping has been hard to attain. 8,9 Shi et al have shown that nitrogen doping reduces the band gap of NaTaO 3 based on their first-principle density functional calculation on the electronic structure of nitrogen-doped NaTaO 3 .…”

“…7 Although Wang 8 and Liu 9 succeeded in nitrogen doping into NaTaO 3 by thermal treatment of NaTaO 3 in NH 3 atmosphere, high concentration nitrogen doping has been hard to attain. 8,9 Shi et al have shown that nitrogen doping reduces the band gap of NaTaO 3 based on their first-principle density functional calculation on the electronic structure of nitrogen-doped NaTaO 3 . 10 Until now, the concentration of doped nitrogen was not controlled well; in addition, the role of doped nitrogen on the photocatalytic activities was hardly studied.…”

Higher visible photocatalytic activities of nitrogen doped In2TiO5 sensitized by carbon nitride

“…N-doped photocatalyst is a focus of study in photocatalytic field. So far, N-TiO 2 [8], N-SrTiO 3 [9,10], N-doped titanate nanotubes [11], N-H 2 Ta 2 O 6 [12], N-NaTaO 3 [13] and N-NaNbO 3 [14], all display good visible light activities. However, to the best of our knowledge, there are few investigations concerning the effects of In 2 TiO 5 doped with nonmetal element on the photocatalytic activity.…”