Abstract
Vanadia-based catalysts have been widely applied in NOx reduction, while the promoting effects of WO3 and MoO3 are still under debate. Herein, we prepared V2O5/TiO2, V2O5-WO3/TiO2, and V2O5-MoO3/TiO2 catalysts and revealed that WO3 and MoO3 enhanced the activity of V2O5/TiO2, especially under wet conditions. In situ DRIFTS, two-dimensional correlation spectroscopy (2D COS), and DFT calculations demonstrated that NH3 adsorbed on Lewis acid sites of V2O5/TiO2, resulting in the formation of NH3ads-L1 (1284 cm−1, Ti sites of O=V–O–Ti) and NH3ads-L2 (1604 cm−1, V=O sites). By using 2D COS, we found that the NH3ads-L1 exhibited higher reactivity towards NO to produce NH2NO* via NH2*, which was promoted by WO3. Moreover, WO3 and MoO3 doping inhibited H2O adsorption, and promoted its desorption by increasing temperature, thus protecting the V=O sites on V2O5/TiO2. Also, 2D COS provided a new perspective for in-depth understanding of the active sites and intermediates in the NH3-SCR reaction.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.