The occurrence of NH₃-SCR (selective catalytic reduction of NO with NH₃) reaction on catalyst surface typically requires acid and redox sites. However, the role of acid-redox interaction on NH₃-SCR performance is still obscure due to complex acidities and entangled acid-redox sites. Herein, three types of model Ce₂(SO₄)₃-CeO₂ catalysts with distinct interfaces are constructed to reveal the effect of acid-redox interaction on NH₃-SCR performance. That is, SO₄^2-/CeO₂-VS (vapor sulfation of ceria) with strong acid-redox interfacial contact, SO₄^2-/CeO₂-WI (wet impregnation), and SO₄^2-/CeO₂-SG (solid grinding) with limited interfaces. It is found the redox property is significantly disturbed as a result of the electron-withdrawing effect from the sulfate. Theoretical result unravels that the introduction of Ce₂(SO₄)₃ retards the oxygen vacancy formation over CeO₂. Due to restricted interfaces in SO₄^2-/CeO₂-SG, the negative influence from acid sites is greatly alleviated. Further mechanism study discloses the weakened acid-redox interaction actually changes the nature of surface NOx species, resulting in the generation of reactive species (*O-N-O* and cis-N₂O₂^2-) and the promotion of surface reaction via Langmuir-Hinshelwood (L-H) mechanism.

在催化剂表面发生 NH ₃ -SCR（NO 与 NH _{3 的}选择性催化还原）反应通常需要酸和氧化还原位点。然而，由于酸度复杂和酸-氧化还原位点缠结，酸-氧化还原相互作用对NH ₃ -SCR 性能的作用仍不清楚。在此，构建了三种具有不同界面的模型Ce ₂ (SO ₄ ) ₃ -CeO ₂催化剂，以揭示酸-氧化还原相互作用对NH ₃ -SCR性能的影响。即，SO ₄ ^2- /CeO ₂ -VS（二氧化铈蒸气硫酸化）与强酸-氧化还原界面接触，SO ₄^2- /CeO ₂ -WI（湿法浸渍）和 SO ₄ ^2- /CeO ₂ -SG（固体研磨）界面有限。发现由于硫酸盐的吸电子效应，氧化还原性能受到显着干扰。理论结果表明，Ce ₂ (SO ₄ ) ₃的引入延缓了CeO _{2 上}氧空位的形成。由于 SO ₄ ^2- /CeO ₂ -SG 中的界面受限，酸性位点的负面影响大大减轻。进一步的机制研究揭示减弱的酸-氧化还原相互作用实际上改变了表面 NO x的性质物种，导致产生活性物种（*ONO*和顺式-N ₂ O ₂ ^2-）并通过 Langmuir-Hinshelwood (LH) 机制促进表面反应。