A Rational Design for Enhanced Catalytic Activity and Durability: Strongly Coupled N‑Doped CrO_x/Ce_0.2Zr_0.8O₂ Nanoparticle Composites

As a classic catalyst for NO oxidation, CrO_x/Ce_0.2Zr_0.8O₂ has been widely researched to improve its intrinsic catalytic activity and stability under complex flue gas environments. Some strategies, such as nanosize reduction, composite catalysts, and transition metal or rare earth ion doping, have been reported to enhance the catalytic properties. However, the commercialization of CrO_x/Ce_0.2Zr_0.8O₂ is greatly hindered by its poor stability under complex flue gas environments. Herein, we reveal a new route to fabricate N-doped CrO_x/Ce_0.2Zr_0.8O₂ nanoparticles, which exhibit not only higher NO conversion but also H₂O and SO₂ tolerance. The morphology and structure were analyzed via X-ray diffraction, transmission electron microscope, et al., investigating the enhancement of N doping. Additionally, the formation of the Ce–O–N–Zr chemical bond and the possible catalytic mechanism were examined by in situ diffuse reflectance infrared Fourier transform spectroscopy, which provided insight into both the fabrication and the catalytic oxidation activity. Finally, density functional theory calculations were applied to expand the design and afford diverse functionality of the catalyst for use in various applications.