Ce<sub>1−x</sub>Fe<sub>x</sub>VO<sub>4</sub> with Improved Activity for Catalytic Reduction of NO with NH<sub>3</sub>
oleh: Li Wang, Junbo Wang, Heping Cheng, Xiangxiang Zhou, Zhen Ma
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2022-05-01 |
Deskripsi
A series of Ce<sub>1−x</sub>Fe<sub>x</sub>VO<sub>4</sub> (x = 0, 0.25, 0.50, 0.75, 1) catalysts prepared by modified hydrothermal synthesis were used for selective catalytic reduction (SCR) of NO<i><sub>x</sub></i> with NH<sub>3</sub>. Among them, Ce<sub>0.5</sub>Fe<sub>0.5</sub>VO<sub>4</sub> showed the highest catalytic activity. The catalysts were characterized by X-ray diffraction (XRD), N<sub>2</sub> adsorption–desorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray fluorescence (XRF), X-ray photoelectron spectroscopy (XPS), temperature-programmed reduction using H<sub>2</sub> (H<sub>2</sub>-TPR), and temperature-programmed desorption of NH<sub>3</sub> (NH<sub>3</sub>-TPD). The results indicated the formation of Ce-Fe-V-O solid solutions. The average oxidation states (AOS) of Ce, Fe, V, and O atoms changed obviously with the incorporation of Fe<sup>3+</sup> into CeVO<sub>4</sub>, and the acidity of Ce<sub>0.5</sub>Fe<sub>0.5</sub>VO<sub>4</sub> differs from that of CeVO<sub>4</sub> and FeVO<sub>4</sub>. The presence of more acid sites and a sharp increase in active oxygen species in Ce<sub>0.5</sub>Fe<sub>0.5</sub>VO<sub>4</sub> effectively improved the selective catalytic reduction (SCR) activity.