We present a tube-shaped Mn-Ni-Ti solid solution for the selective catalytic reduction of NO_x with NH₃ (NH₃-SCR) through a facile self-templated urea-homogeneous precipitation method, which leads to the fine dispersion of the MnO_x and NiO_x active species in the TiO₂ lattice. The ratio of Mn/Ni/Ti is an important factor to affect the crystallinity of Mn-Ni-Ti solid sulotion, and the catalyst with a Mn/Ni/Ti ratio of 2/3/5 (Mn2-Ni3) exhibits the significant structure distortion. The abundant surface defects induce more generation of Mn⁴⁺ species, surface adsorbed oxygen and Lewis acid sites, and acclerate the adsorption and activation of NO molecules. The appropriate Mn/Ni ratio inhibits the competitive adsorption of NH₃ with NO, and facilitates the Langmuir-Hinshelwood (L-H) mechanism to form N₂, which acts as a much more rapid pathway in comparison to the parallel one following Eley-Rideal (E-R) mechanism. The readily occurence of L-H mechanism significantly improves the SCR performance of catalyst.

我们提出了一个选择性催化还原NO的管形Mn-Ni的钛固溶体_X与NH ₃（NH ₃ -SCR）通过一个浅显自模板脲-均匀沉淀法，这导致的微细分散TiO ₂晶格中的MnO _x和NiO _x活性物质。Mn / Ni / Ti比是影响Mn-Ni-Ti固体悬浮液结晶度的重要因素，Mn / Ni / Ti比为2/3/5（Mn2-Ni3）的催化剂表现出显着的影响。结构变形。大量的表面缺陷导致更多的Mn ⁴⁺生成分子，表面吸附的氧和路易斯酸位点，并加速了NO分子的吸附和活化。适当的Mn / Ni比值会抑制NH ₃与NO的竞争性吸附，并促进Langmuir-Hinshelwood（LH）机制形成N ₂，与Eley-Rideal（ ER）机制。LH机理的容易出现大大改善了催化剂的SCR性能。